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DR ANTHONY MELVIN CRASTO, Born in Mumbai in 1964 and graduated from Mumbai University, Completed his Ph.D from ICT, 1991,Matunga, Mumbai, India, in Organic Chemistry, The thesis topic was Synthesis of Novel Pyrethroid Analogues, Currently he is working with AFRICURE PHARMA, ROW2TECH, NIPER-G, Department of Pharmaceuticals, Ministry of Chemicals and Fertilizers, Govt. of India as ADVISOR, earlier assignment was with GLENMARK LIFE SCIENCES LTD, as CONSUlTANT, Retired from GLENMARK in Jan2022 Research Centre as Principal Scientist, Process Research (bulk actives) at Mahape, Navi Mumbai, India. Total Industry exp 32 plus yrs, Prior to joining Glenmark, he has worked with major multinationals like Hoechst Marion Roussel, now Sanofi, Searle India Ltd, now RPG lifesciences, etc. He has worked with notable scientists like Dr K Nagarajan, Dr Ralph Stapel, Prof S Seshadri, etc, He did custom synthesis for major multinationals in his career like BASF, Novartis, Sanofi, etc., He has worked in Discovery, Natural products, Bulk drugs, Generics, Intermediates, Fine chemicals, Neutraceuticals, GMP, Scaleups, etc, he is now helping millions, has 9 million plus hits on Google on all Organic chemistry websites. His friends call him Open superstar worlddrugtracker. His New Drug Approvals, Green Chemistry International, All about drugs, Eurekamoments, Organic spectroscopy international, etc in organic chemistry are some most read blogs He has hands on experience in initiation and developing novel routes for drug molecules and implementation them on commercial scale over a 32 PLUS year tenure till date Feb 2023, Around 35 plus products in his career. He has good knowledge of IPM, GMP, Regulatory aspects, he has several International patents published worldwide . He has good proficiency in Technology transfer, Spectroscopy, Stereochemistry, Synthesis, Polymorphism etc., He suffered a paralytic stroke/ Acute Transverse mylitis in Dec 2007 and is 90 %Paralysed, He is bound to a wheelchair, this seems to have injected feul in him to help chemists all around the world, he is more active than before and is pushing boundaries, He has 100 million plus hits on Google, 2.5 lakh plus connections on all networking sites, 100 Lakh plus views on dozen plus blogs, 227 countries, 7 continents, He makes himself available to all, contact him on +91 9323115463, email amcrasto@gmail.com, Twitter, @amcrasto , He lives and will die for his family, 90% paralysis cannot kill his soul., Notably he has 38 lakh plus views on New Drug Approvals Blog in 227 countries......https://newdrugapprovals.wordpress.com/ , He appreciates the help he gets from one and all, Friends, Family, Glenmark, Readers, Wellwishers, Doctors, Drug authorities, His Contacts, Physiotherapist, etc He has total of 32 International and Indian awards

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TOLVAPTAN


TOLVAPTAN

的合成

N-(4-{[(5R)-7-chloro-5-hydroxy-2,3,4,5-tetrahydro-1H-1-benzazepin-1-yl]carbonyl}-3-methylphenyl)-2-methylbenzamide

Formula C26H25ClN2O3 
Mol. mass 448.941 g/mol

150683-30-0 CAS NO

+ form  331947-66-1 Rform

OPC-41061

Otsuka…..innovator

UPDATE 2022

Tolvaptan sodium phosphate, Samtasu,

トルバプタンリン酸エステルナトリウム
2022/3/28 JAPAN PPROVED
Formula
C26H24ClN2O6P. 2Na
CAS
 
Mol weight
572.8849

Tolvaptan sodium phosphate (JAN).png

Tolvaptan sodium phosphate

disodium;[(5R)-7-chloro-1-[2-methyl-4-[(2-methylbenzoyl)amino]benzoyl]-2,3,4,5-tetrahydro-1-benzazepin-5-yl] phosphate

European Medicines Agency (EMA) Accepts Otsuka’s Marketing Authorisation Application (MAA) for Tolvaptan, an Investigational Compound for Autosomal Dominant Polycystic Kidney Disease (ADPKD)

•Tolvaptan was discovered by Otsuka in Japan and, if approved by the EMA, would become the first pharmaceutical therapy in Europe for patients with ADPKD
•ADPKD is an inherited genetic disease that causes cyst growth in the kidneys, which gradually impairs their functioning. There is no current pharmaceutical treatment option
•Otsuka’s development of tolvaptan as a treatment for ADPKD illustrates the company’s commitment to address significant patient needs for diseases that traditionally have not been a priority for the pharmaceutical industry

TOKYO–(BUSINESS WIRE)–Otsuka Pharmaceutical Co., Ltd. announced today that the European Medicines Agency (EMA) has accepted the submission of a marketing authorisation application (MAA) for the potential approval of tolvaptan for the treatment of autosomal dominant polycystic kidney disease (ADPKD). Phase III clinical trial results that form the basis of the regulatory filing were published in the New England Journal of Medicine.

http://www.pharmalive.com/ema-accepts-otsukas-maa-for-tolvaptan

Tolvaptan is a selective vasopressin V2-receptor antagonist with an affinity for the V2-receptor that is 1.8 times that of native arginine vasopressin (AVP).

Tolvaptan is (±)-4′-[(7-chloro-2,3,4,5-tetrahydro-5-hydroxy-1H-1-benzazepin-1-yl) carbonyl]-otolu-m-toluidide. The empirical formula is C26H25ClN2O3. Molecular weight is 448.94. The chemical structure is:

SAMSCA® (tolvaptan) Structural Formula Illustration

SAMSCA tablets for oral use contain 15 mg or 30 mg of tolvaptan. Inactive ingredients include corn starch, hydroxypropyl cellulose, lactose monohydrate, low-substituted hydroxypropyl cellulose, magnesium stearate and microcrystalline cellulose and FD&C Blue No. 2 Aluminum Lake as colorant.

SEE NEW UPDATE AT END OF PAGE

Tolvaptan (INN), also known as OPC-41061, is a selective, competitive vasopressin receptor 2 antagonist used to treat hyponatremia (low blood sodium levels) associated withcongestive heart failurecirrhosis, and the syndrome of inappropriate antidiuretic hormone(SIADH). Tolvaptan was approved by the U.S. Food and Drug Administration (FDA) on May 19, 2009, and is sold by Otsuka Pharmaceutical Co. under the trade name Samsca and in India is manufactured & sold by MSN laboratories Ltd. under the trade name Tolvat & Tolsama.

ChemSpider 2D Image | Tolvaptan | C26H25ClN2O3

Tolvaptan is also in fast-track clinical trials[2] for polycystic kidney disease. In a 2004 trial, tolvaptan, when administered with traditional diuretics, was noted to increase excretion of excess fluids and improve blood sodium levels in patients with heart failure without producing side effects such as hypotension (low blood pressure) or hypokalemia(decreased blood levels of potassium) and without having an adverse effect on kidney function.[3] In a recently published trial (TEMPO 3:4 ClinicalTrials.gov number, NCT00428948) the study met its primary and secondary end points. Tolvaptan, when given at an average dose of 95 mg per day over a 3-year period, slowed the usual increase in kidney volume by 50% compared to placebo (2.80% per year versus 5.51% per year, respectively, p<0.001) and reduced the decline in kidney function when compared with that of placebo-treated patients by approximately 30% (reciprocal serum creatinine, -2.61 versus -3.81 (mg/mL)-1 per year, p <0.001)[4]

Tolvaptan was first approved by the U.S. Food and Drug Administration (FDA) on May 19, 2009, then approved by the European Medicines Agency (EMA) on August 3, 2009 and approved by Pharmaceuticals and Medical Devices Agency of Japan on Feb 4, 2013. It was developed and marketed as Samsca® by Otsuka in the US, DE and JP.

UPDATED

Tolvaptan is a selective vasopressin V2-receptor antagonist with an affinity for the V2-receptor that is 1.8 times that of native arginine vasopressin (AVP) and that is 29 times greater than for the V1a-receptor. When taken orally, 15 to 60 mg doses of tolvaptan antagonize the effect of vasopressin and cause an increase in urine water excretion that results in an increase in free water clearance (aquaresis), a decrease in urine osmolality, and a resulting increase in serum sodium concentrations. It is indicated for the treatment of clinically significant hypervolemic and euvolemic hyponatremia [serum sodium < 125 mEq/L or less marked hyponatremia that is symptomatic and has resisted correction with fluid restriction], including patients with heart failure, cirrhosis, and syndrome of inappropriate antidiuretic hormone (SIADH).

Samsca® is available as tablet for oral use, containing 7.5 mg/15 mg/30 mg of free Tolvaptan. The recommended starting dose is 15 mg once daily and it may be increased at intervals ≥ 24 hr to 30 mg once daily, and to a maximum of 60 mg once daily as needed to raise serum sodium.

 
 

Synthesis Reference

Bandi Parthasaradhi Reddy, “PROCESS FOR PREPARING TOLVAPTAN INTERMEDIATES.” U.S. Patent US20130190490, issued July 25, 2013.

US20130190490

Route 1

Reference:1. US5258510A.

Route 4

Reference:1. CN102060769B.

Route 5
 
 

SYN

SYN

Chemical synthesis:[5] Tolvaptan.png

 

Tolvaptan is chemically, N-[4-[(7-chloro-2,3,4,5-tetrahydro-5-hydroxy1H-1-benzazepin-1-yl)carbonyl]-3-methylphenyl]-2-methylbenzamide. Tolvaptan is represented by the following structure:

Figure US20130190490A1-20130725-C00001

Tolvaptan, also known as OPC-41061, is a selective, competitive arginine vasopressin receptor 2 antagonist used to treat hyponatremia (low blood sodium levels) associated with congestive heart failure, cirrhosis, and the syndrome of inappropriate antidiuretic hormone (SIADH). Tolvaptan is sold by Otsuka Pharmaceutical Co. under the trade name Samsca.

Tolvaptan and its process for preparation were disclosed in U.S. Pat. No. 5,258,510.

Processes for the preparation of 7-chloro-2,3,4,5-tetrahydro-1H-1-benzazepin-5-one, 7-chloro-1-(2-methyl-4-nitrobenzoyl)-5-oxo-2,3,4,5-tetrahydro-1H-1-benzazepine and 7-chloro-1-[2-methyl-4-[(2-methylbenzoyl)amino]benzoyl]-5-oxo-2,3,4,5-tetrahydro-1H-1-benzazepine were reported in Bioorganic & medicinal chemistry 7 (1999), 1743-1754. According to the journal, 7-chloro-2,3,4,5-tetrahydro-1H-1-benzazepin-5-one can be prepared by reacting 7-chloro-4-ethoxycarbonyl-5-oxo-N-p-toluenesufonyl-2,3,4,5-tetrahydro-1H-1-benzazepine with acetic acid in the presence of hydrochloric acid and water to obtain 7-chloro-5-oxo-2,3,4,5-tetrahydro-1-p-toluenesulfonyl-1H-1-benzazepine, and then reacted with polyphospholic acid. According to the journal, 7-chloro-1-(2-methyl-4-nitrobenzoyl)-5-oxo-2,3,4,5-tetrahydro-1H-1-benzazepine can be prepared by reacting 7-chloro-5-oxo-2,3,4,5-tetrahydro-1H-1-benzazepine with 2-methyl-4-nitobenzoyl chloride in the presence of triethylamine.

According to the journal, 7-chloro-1-[2-methyl-4-[(2-methylbenzoyl)amino]benzoyl]-5-oxo-2,3,4,5-tetrahydro-1H-1-benzazepine can be prepared by reacting 1-(4-amino-2-methylbenzoyl)-7-chloro-5-oxo-2,3,4,5-tetrahydro-1H-1-benzazepine with 2-methylbenzoylchloride in the presence of triethylamine.

PCT publication no. WO 2007/026971 disclosed a process for the preparation oftolvaptan can be prepared by the reduction of 7-chloro-1-[2-methyl-4-(2-methylbenzoylamino)benzoyl]-2,3,4,5-tetrahydro-1H-1-benzazepin-5-one with sodium borohydride.

7-Chloro-2,3,4,5-tetrahydro-1H-1-benzazepin-5-one is a key intermediate for the preparation of tolvaptan.

Biooganic and Medicinal Chemistry I (2007) 6455-6458, Biooganic andMedicinal Chemistry 14 (2000) 2493-2495 reported in the literature of the intermediate 2 – carboxylic acid -5 – (2 – methyl-benzoylamino) toluene synthesis method,

5-Chloro-2-nitrobenzoic acid (I) was converted into methyl ester (II) using dimethyl sulfate and K2CO3 in acetone. The nitro group of (II) was then reduced with SnCl2 to afford aniline (III), which was protected as the p-toluenesulfonamide (IV) with tosyl chloride in pyridine. Alkylation of (IV) with ethyl 4-bromobutyrate (V) yielded diester (VI). Subsequent Dieckmann cyclization of (VI) in the presence of potassium tert-butoxide provided benzazepinone (VIIa-b) as a mixture of ethyl and methyl esters, which was decarboxylated to (VIII) by heating with HCl in AcOH. Deprotection of the tosyl group of (VIII) was carried out in hot polyphosphoric acid. The resulting benzazepinone (IX) was condensed with 2-methyl-4-nitrobenzoyl chloride (X) to give amide (XI). After reduction of the nitro group of (XI) to the corresponding aniline (XII), condensation with 2-methylbenzoyl chloride (XIII) provided diamide (XIV). Finally, ketone reduction in (XIV) by means of NaBH4 led to the target compound.

……………………………………….

PATENT

CN102382053AFigure CN102382053AD00031

……………………………………………..

PATENT

CN102060769

Figure CN102060769BC00021

Synthesis of Intermediate III: 1.

Example

  2-methyl-4-nitrobenzoic acid (available from Alfa Aesar Tianjin Chemical Co., purity> 99%, 25g,

0.14mol) was added to a 250ml reaction flask, is reacted with thionyl chloride under reflux conditions for 3h, thionyl chloride was distilled off under reduced pressure to give 2-methyl-4-nitrobenzoyl chloride (26.Sg, light yellow oily liquid), without purification, was used directly in the next step.

  Intermediate II (20g, 0.1moI) and 2_ methyl _4_ nitrobenzoylchloride (22.4g, 0.llmol) was added to a 250ml reaction flask. Dichloromethane (50ml), cooled to ice bath with stirring to dissolve O~5 ° C, was slowly added dropwise N- methylmorpholine (11.2g, 0.llmol), Bi dropwise with stirring while, at room temperature the reaction 4h. TLC [developing solvent: ethyl acetate – petroleum ether (I: I), hereinafter] is displayed after completion of the reaction, saturated aqueous sodium bicarbonate (20ml), stirred for lOmin, filtered, the filter cake with dichloromethane (15ml X 2 ) washing. The filtrate and washings were combined, washed with saturated sodium chloride solution (30ml X 3), dried over anhydrous sodium sulfate and filtered. The filtrate under reduced pressure to recover the solvent, the residue was recrystallized from anhydrous methanol to give a white powder 111 (27.5g, 75.2%), mp 154.8 ~155.6 ° C. Purity 97.9% (HPLC normalization method).

Synthesis of Intermediate IV:

Intermediate III (10g, 28mmol) was added to a 250ml reaction flask, concentrated hydrochloric acid (40ml) and ethanol (50ml), with stirring, was slowly added dropwise stannous chloride (20g, 88mmol) in ethanol (40ml) . Bi room temperature drops 5h. After TLC showed completion of the reaction, ethanol was distilled off under reduced pressure to about 70ml, the residue was -10 ° C -0 ° C allowed to stand overnight to cool. Filtered, and the filter cake was washed with water poured into water (40ml) in. Plus 20% sodium hydroxide solution (approximately 60ml) was adjusted to pH 9. Filtered, washed with ethanol and recrystallized to give a pale yellow powdered solid IV (6.3g, 68.7%), mp 190.4~191.1 ° C. Purity 97.2% (HPLC normalization method).

Synthesis of intermediate V:

  Intermediate IV (5g, 15mmol) and triethylamine (2.3g, 23mmol) was added followed by IOOml reaction flask was added dichloromethane (30ml), stir until dissolved. Solution of o-methylbenzoyl chloride (2.8g, 18mmol), dropwise at room temperature completion of the reaction Ih0 TLC showed the reaction was complete was poured into ice-water (about 40ml) in, (20ml X 3) and extracted with dichloromethane, the combined organic phases, and saturated sodium chloride solution successively (25ml X 3), dried over anhydrous sodium sulfate and filtered with 5% hydrochloric acid (25ml X 3). The filtrate under reduced pressure to recover the solvent (about 50ml), dried over anhydrous methanol residue – petroleum ether (2: 1) and recrystallized to give white crystals of Intermediate V (6.2g, 90.9%), mp 121.1 ~123.6 ° C. Purity 98.6% (HPLC normalization method).

Synthesis of tolvaptan: Example 4

Intermediate V (5g, Ilmmol) IOOml added to the reaction flask, was added anhydrous methanol (25ml), stirred and then added portionwise sodium borohydride (0.65g, 17mmol) to the reaction mixture, addition was complete the reaction at room temperature lh. After TLC showed the reaction was complete, the methanol recovered under reduced pressure (approximately 20ml), the residue was added methylene chloride (25ml), (25mlX3) and washed with saturated sodium chloride solution. Anhydrous sodium sulfate and filtered, and the filtrate under reduced pressure to recover the solvent, the residue with absolute methanol – petroleum ether (2: 1) and recrystallized tolvaptan white crystals (4.85g, 96.6%), mp 220.1~221.5 ° C. Purity 99.2% (HPLC normalization method). ES1-HRMS (C26H25C1N203, m / z) found (calc): 447.1476 (447.1481) [MH] – “

…………..

PATENT

http://www.google.com/patents/WO2012046244A1?cl=en

Tolvaptan is chemically, N-[4-[(7-chloro-2,3,4,5-tetrahydro-5-hydroxylH-l- benzazepin- 1 -yl)carbonyl]-3-methylphenyl]-2-methylbenzamide. Tolvaptan is represented by the following structure:

Tolvaptan, also known as OPC-41061, is a selective, competitive arginine vasopressin receptor 2 antagonist used to treat hyponatremia (low blood sodium levels) associated with congestive heart failure, cirrhosis, and the syndrome of inappropriate antidiuretic hormone (SIADH). Tolvaptan is sold by Otsuka Pharmaceutical Co. under the trade name Samsca.

Tolvaptan and its process for preparation were disclosed in U.S. patent no. 5,258,510. Processes for the preparation of 7-chloro-2,3,4,5-tetrahydro-lH-l-benzazepin-5- one, 7-chloro-l-(2-methyl-4-nitrobenzoyl)-5-oxo-2,3,4,5-tetrahydro-lH-l-benzazepine and 7-chloro- 1 -[2-methyl-4-[(2-methylbenzoyl)amino]benzoyl]-5-oxo-2,3,4,5- tetrahydro-lH-l-benzazepine were reported in Bioorganic & medicinal chemistry 7 (1999), 1743-1754. According to the journal, 7-chloro-2,3,4,5-tetrahydro-lH-l- benzazepin-5-one can be prepared by reacting 7-chloro-4-ethoxycarbonyl-5-oxo-N-p- toluenesufonyl-2,3,4,5-tetrahydro-lH-l-benzazepine with acetic acid in the presence of hydrochloric acid and water to obtain 7-chloro-5-oxo-2,3,4,5-tetrahydro-l-p- toluenesulfonyl-lH-l-benzazepine, and then reacted with polyphospholic acid.

According to the journal, 7-chloro- 1 -(2 -methyl-4-nitrobenzoyl)-5-oxo-2,3,4,5- tetrahydro-lH-l-benzazepine can be prepared by reacting 7-chloro-5-oxo-2,3,4,5- tetrahydro-lH-l-benzazepine with 2-methyl-4-nitobenzoyl chloride in the presence of triethylamine.

According to the journal, 7-chloro- l-[2-methyl-4-[(2- methylbenzoyl)amino]benzoyl]-5-oxo-2,3,4,5-tetrahydro-lH-l-benzazepine can be prepared by reacting l-(4-amino-2-methylbenzoyl)-7-chloro-5-oxo-2,3,4,5-tetrahydro- lH-l-benzazepine with 2-methylbenzoylchloride in the presence of triethylamine.

PCT publication no. WO 2007/026971 disclosed a process for the preparation of tolvaptan can be prepared by the reduction of 7-chloro- l-[2-methyl-4-(2- methylbenzoylamino)benzoyl]-2,3,4,5-tetrahydro-lH-l-benzazepin-5-one with sodium borohydride.

7-Chloro-2,3,4,5-tetrahydro-lH-l-benzazepin-5-one is a key intermediate for the preparation of tolvaptan.

 SYNTHESIS CONSTRUCTION

to1

TO0

to2

to3

to4

to5

Reference example 1 :

Preparation of methyl 5-chloro-2-nitrobenzoate

Potassium carbonate (515 gm) was added to a solution of 5-chloro-2-nitro benzoic acid (500 gm) in acetone (2750 ml) at room temperature. Dimethyl sulphate (306.5 gm) was added to the reaction mixture slowly and heated to reflux for 30 minutes. The reaction mass was filtered and then concentrated to obtain a residual mass. The residual mass was poured to the ice water and extracted with methylene chloride. The solvent was distilled off under reduced pressure to obtain a residual solid of methyl 5- chloro-2-nitrobenzoate (534 gm). Reference example 2:

Preparation of methyl 2-amino-5-chlorobenzoate

A mixture of methyl 5-chloro-2-nitrobenzoate (534 gm) as obtained in reference example 1 and concentrated hydrochloric acid (2250 ml) was added to ethyl acetate (1120 ml). To the reaction mixture was added a solution of tin chloride (1680 gm) in ethyl acetate (2250 ml). The reaction mass was stirred for 16 hours at room temperature and then poured to the ice water. The pH of the reaction mass was adjusted to 8.0 to 9.0 with aqueous sodium hydroxide solution (2650 ml). The separated aqueous layer was extracted with ethyl acetate and then concentrated to obtain a residual solid of methyl 2- amino-5-chlorobenzoate (345 gm). Reference example 3:

Preparation of methyl 5-chIoro-2-(N-p-toluenesulfonyl)aminobenzoate

To a solution of methyl-2-amino-5-chloro benzoate (345 gm) as obtained in reference example 2 in pyridine (1725 ml) was added p-toluenesulfonyl chloride (425 gm). The reaction mixture was stirred for 2 hours at room temperature and poured to the ice water. The separated solid was filtered and dried to obtain 585 gm of methyl 5- chloro-2-(N-p-toluenesulfonyl)aminobenzoate.

Reference example 4:

Preparation of methyl 5-chloro-2-[N-(3-ethoxycarbonyI)propyI-N-p- toluenesulfonyl] aminobenzoate

Methyl 5-chloro-2-(N-p-toluenesulfonyl)aminobenzoate (585 gm) as obtained in reference example 3, ethyl-4-bromo butyrate (369.6 gm) and potassium carbonate (664 gm) in dimethylformamide (4400 ml) were added at room temperature. The contents were heated to 120°C and maintained for 2 hours. The reaction mass was poured into water and filtered. The solid obtained was dried to give 726 gm of methyl 5-chloro-2-[N- (3 -ethoxycarbonyl)propyl-N-p-toluenesulfonyl] aminobenzoate.

Reference example 5:

Preparation of 7-chloro-4-ethoxycarbonyI-5-oxo-N-p-toluenesufonyl-2,3,4,5- tetrahydro-lH-l-benzazepine

To a heated mixture of potassium tetrabutoxide (363 gm) in toluene (1000 ml) at 70°C was added portion wise methyl 5-chloro-2-[N-(3-ethoxycarbonyl)propyl-N-p- toluenesulfonyl]aminobenzoate (726 gm) as obtained in reference example 4. The contents were heated to reflux and maintained for 30 minutes. The reaction mass was then cooled to room temperature and then poured to the ice water. The layers were separated and the aqueous layer was extracted with toluene. The solvent was distilled off under reduced pressure to obtain a residual solid of 7-chloro-4-ethoxycarbonyl-5-oxo-N- p-toluenesufonyl-2,3,4,5-tetrahydro-lH-l-benzazepine (455 gm).

Example 1:

Preparation of 7-chIoro-5-oxo-2,3,4,5-tetrahydro-lH-l-benzazepine

7-Chloro-4-ethoxycarbonyl-5-oxo-N-p-toluenesufonyl-2,3,4,5-tetrahydro- 1 H- 1 – benzazepine (455 gm) as obtained in reference example 5 was added to aqueous sulfuric acid (80%, 2275 ml). The contents heated to 75°C and maintained for 2 hours. The reaction mass was then cooled to room temperature and then poured to the ice water. The pH of the reaction mass was adjusted to 7.5 to 8.0 with sodium hydroxide solution (2575 ml). The solid obtained was collected by filtration and dried to give 160 gm of 7- chloro-5-oxo-2,3 ,4,5-tetrahydro- 1 H- 1 -benzazepine.

Example 2:

Preparation of 7-chIoro-l-(2-methyl-4-nitrobenzoyl)-5-oxo-2,3,4,5-tetrahydro-lH-l- benzazepine

7-Chloro-5-oxo-2,3,4,5-tetrahydro-lH-l -benzazepine (160 gm) as obtained in example 1 was dissolved in methylene dichloride (480 ml) and then added aqueous sodium bicarbonate solution (20%, 68.75 gm). The reaction mixture was then cooled to 0 to 5°C and then added 2-methyl-4-nitrobenzoylchloride (180 gm) slowly. The pH of the reaction mass was adjusted to 7.0 to 8.0 with aqueous sodium bicarbonate solution (170 ml). The layers were separated and the aqueous layer was extracted with methylene chloride. The solvent was distilled off under reduced pressure to obtain a residual mass. To the residual mass was dissolved in isopropyl alcohol (7300 ml) and maintained for 2 hours at reflux temperature. The separated solid was filtered and dried to obtain 250 gm of 7-chloro-l-(2-methyl-4-nitrobenzoyl)-5-oxo-2,3,4,5-tetrahydro-lH-l-benzazepine. Example 3:

Preparation of l-(4-amino-2-methylbenzoyl)-7-chIoro-5-oxo-2,3,4,5-tetrahydro-lH- 1-benzazepine

7-Chloro- 1 -(2-methyl-4-nitrobenzoyl)-5-oxo-2,3 ,4,5-tetrahydro- 1 H- 1 – benzazepine (250 gm) as obtained in example 2 was dissolved in methanol (575 ml) and then added a solution of tin chloride (630 gm) in methanol (1130 ml). The reaction mixture was stirred for 16 hours at room temperature and then poured to the ice water. The pH of the reaction mass was adjusted to 8.0 to 9.0 with sodium hydroxide solution (1250 ml). The layers were separated and the aqueous layer was extracted with ethyl acetate. The solvent was distilled off under vacuum to obtain a residual solid of l-(4- amino-2-methylbenzoyl)-7-chloro-5-oxo-2,3,4,5-tetrahydro- 1 H- 1 -benzazepine (185 gm).

Example 4:

Preparation of 7-chloro-l-[2-methyl-4-[(2-methylbenzoyl)amino]benzoyl]-5-dxo- 2,3,4,5-tetrahydro-lH-l-benzazepine

1 -(4-Amino-2-methylbenzoyl)-7-chloro-5-oxo-2,3 ,4,5-tetrahydro- 1 H- 1 – benzazepine (185 gm) as obtained in example 3 was dissolved in methylene chloride (4000 ml) and then added sodium bicarbonate solution (10%, 47.3 gm). The reaction mass was cooled to 0 to 5°C and then added 2-methyl benzoyl chloride (95.7 gm) slowly. -The pH of the reaction mass was adjusted to 7.0 to 8.0 with aqueous sodium bicarbonate solution (120 ml). The separated aqueous layer was extracted with methylene chloride and then concentrated to obtain a residual solid of 7-chloro-l-[2- methyl-4-[(2-methylbenzoyl)amino]benzoyl]-5-oxo-2,3,4,5-tetrahydro- 1 H- 1 – benzazepine (185 gm). Example 5:

Preparation of tolvaptan

7-Chloro- 1 -[2-methyl-4-[(2-methylbenzoyl)amino]benzoyl]-5-oxo-2,3,4,5- tetrahydro-lH-1 -benzazepine (63 gm) as obtained in example 4 was dissolved in methanol (570 ml) and then added sodium borohydride (2.07 gm) at room temperature. The reaction mass was stirred for 1 hour and pH of the reaction mass was adjusted to 6.0 to 7.0 with hydrochloric acid solution (1%, 630 ml). The separated solid was filtered and dried to obtain 57 gm of tolvaptan.

……………….

t1.

Process used to prepare Tolvaptan involves condensing 7-chloro-1, 2, 3, 4-tetrahydro-benzo[b]azepin-5-one with 2-methyl, 4-nitro benzoyl chloride, followed by reduction using SnCl2/HCl catalyst resulting in amine which is then condensed with o-toluoyl chloride followed by reduction with sodium borohydride to give Tolvaptan

///////////

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SYN 1

Synthetic Reference

Cordero-Vargas, Alejandro; Quiclet-Sire, Beatrice; Zard, Samir Z. A flexible approach for the preparation of substituted benzazepines: Application to the synthesis of tolvaptan. Bioorganic & Medicinal Chemistry. Volume 14. Issue 18. Pages 6165-6173. 2006.

SYN 2

Synthetic Reference

Torisawa, Yasuhiro; Abe, Kaoru; Muguruma, Yasuaki; Fujita, Shigekazu; Ogawa, Hidenori; Utsumi, Naoto; Miyake, Masahiro. Process for preparation of benzoylaminobenzoylbenzazepinones by reaction of benzazepinones with benzoylaminophenyl halides in the presence of carbonylating agents. Assignee Otsuka Pharmaceutical Co.,

SYN 3

Synthetic Reference

Zard, Samir; Cordero Vargas, Alejandro; Sire, Beatrice. Improved process for the preparation of benzazepines and their derivatives. Assignee Centre National de la Recherche Scientifique CNRS, Fr.; Ecole Polytechnique. FR 2867187. (2005).

SYN 4

Synthetic Reference

Gao, Junlong; Li, Peng; Liu, Kai; Guo, Dapeng. Method for preparing high-purity Tolvaptan intermediate. Assignee Jiangsu Hengrui Medicine Co., Ltd., Peop. Rep. China. CN 108503586. (2018).

SYN 5

Synthetic Reference

Han, Shin; Jeon, Seong Hyeon; Lee, Shin Yoon. Improved method for preparing synthetic intermediates for tolvaptan. Assignee Hexa Pharmatec Co., Ltd., S. Korea. JP 2018012690. (2018).

SYN 6

Synthetic Reference

Guo, Xinfu; Wang, Qiang; Liu, Zhaoguo; Wang, Zhipeng. Preparation method of tolvaptan. Assignee Tianjin Taipu Pharmaceutical Co., Ltd., Peop. Rep. China. CN 106883175. (2017).

SYN 7

Synthetic Reference

Lixin, Juanzi; Li, Jianzhi; Ma, Xilai; Chi, Wangzhou; Liu, Hai; Hu, Xuhua; Zheng, Xiaoli; Zhai, Zhijun; Li, Jianxun. Process for the preparation of tolvaptan. Assignee Shanghai Tianci International Pharmaceutical Co., Ltd., Peop. Rep. China. CN 105753735. (2016).

STR8

Synthetic Reference

Patel, Dhaval J.; Shah, Tejas C.; Singh, Manoj Kumar. A process for the preparation of tolvaptan. Assignee Cadila Healthcare Limited, India. IN 2012MU01559. (2014).

STR9

Synthetic Reference

Sethi, Madhuresh Kumar; Rawat, Vijendrasingh; Thirunavukarasu, Jayaprakash; Yerramala, Raja Krishna; Kumar, Anish. Improved process for the preparation of tolvaptan. Assignee Matrix Laboratories Ltd., India. IN 2011CH01303. (2013).

/////////////////////

t2 t3 t4

Title: Tolvaptan
CAS Registry Number: 150683-30-0
CAS Name: N-[4-[(7-Chloro-2,3,4,5-tetrahydro-5-hydroxy-1H-1-benzazepin-1-yl)carbonyl]-3-methylphenyl]-2-methylbenzamide
Additional Names: 7-chloro-5-hydroxy-1-[2-methyl-4-(2-methylbenzoylamino)benzoyl]-2,3,4,5-tetrahydro-1H-1-benzazepine
Manufacturers’ Codes: OPC-41061
Molecular Formula: C26H25ClN2O3
Molecular Weight: 448.94
Percent Composition: C 69.56%, H 5.61%, Cl 7.90%, N 6.24%, O 10.69%
Literature References: Nonpeptide arginine vasopressin V2 receptor antagonist. Prepn: H. Ogawa et al., WO 9105549; eidem, US 5258510 (1991, 1993 both to Otsuka); K. Kondo et al., Bioorg. Med. Chem. 7, 1743 (1999). Pharmacology: Y. Yamamura et al., J. Pharmacol. Exp. Ther. 287, 860 (1998). Clinical trial in heart failure: M. Gheorghiade et al., J. Am. Med. Assoc. 291, 1963 (2004).
Properties: Colorless prisms, mp 225.9°.
Melting point: mp 225.9°
Therap-Cat: In treatment of congestive heart failure.
Keywords: Vasopressin Receptor Antagonist.

  1. Shoaf S, Elizari M, Wang Z, et al. (2005). “Tolvaptan administration does not affect steady state amiodarone concentrations in patients with cardiac arrhythmias”. J Cardiovasc Pharmacol Ther 10 (3): 165–71. doi:10.1177/107424840501000304PMID 16211205.
  2.  Otsuka Maryland Research Institute, Inc.
  3. Gheorghiade M, Gattis W, O’Connor C, et al. (2004). “Effects of tolvaptan, a vasopressin antagonist, in patients hospitalized with worsening heart failure: a randomized controlled trial”. JAMA 291 (16): 1963–71. doi:10.1001/jama.291.16.1963PMID 15113814.
  4. (2012) Tolvaptan in Patients with Autosomal Dominant Polycystic Kidney Disease
  5. Kondo, K.; Ogawa, H.; Yamashita, H.; Miyamoto, H.; Tanaka, M.; Nakaya, K.; Kitano, K.; Yamamura, Y.; Nakamura, S.; Onogawa, T.; et al.; Bioor. Med. Chem. 1999, 7, 1743.
  6. http://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm350185.htm?source=govdelivery
  • Gheorghiade M, Niazi I, Ouyang J et al. (2003). “Vasopressin V2-receptor blockade with tolvaptan in patients with chronic heart failure: results from a double-blind, randomized trial”. Circulation 107 (21): 2690–6. doi:10.1161/01.CIR.0000070422.41439.04.PMID 12742979.

G. R. Belum, V. R. Belum, S. K. Chaitanya Arudra, and B. S. N. Reddy, “The Jarisch-Herxheimer reaction: revisited,” Travel Medicine and Infectious Disease, vol. 11, no. 4, pp. 231–237, 2013.
H. D. Zmily, S. Daifallah, and J. K. Ghali, “Tolvaptan, hyponatremia, and heart failure,” International Journal of Nephrology and Renovascular Disease, vol. 4, pp. 57–71, 2011.
M. N. Ferguson, “Novel agents for the treatment of hyponatremia: a review of conivaptan and tolvaptan,” Cardiology in Review, vol. 18, no. 6, pp. 313–321, 2010.
H. Ogawa, H. Miyamoto, K. Kondo, et al., US5258510, 1993.
K. Kondo, H. Ogawa, H. Yamashita et al., “7-Chloro-5-hydroxy-1-[2-methyl-4-(2-methylbenzoylamino)benzoyl]-2,3,4,5- tetrahydro-1H-1-benzazepine (OPC-41061): a potent, orally active nonpeptide arginine vasopressin V2 receptor antagonist,” Bioorganic and Medicinal Chemistry, vol. 7, no. 8, pp. 1743–1754, 1999.

WO2012046244A1 * Aug 23, 2011 Apr 12, 2012 Hetero Research Foundation Process for preparing tolvaptan intermediates
CN102060769A * Dec 20, 2010 May 18, 2011 天津药物研究院 Preparation method of tolvaptan
CN102060769B Dec 20, 2010 Sep 18, 2013 天津药物研究院 Preparation method of tolvaptan
US9024015 Aug 23, 2011 May 5, 2015 Hetero Research Foundation Process for preparing tolvaptan intermediates
Cited Patent Filing date Publication date Applicant Title
CN101817783A May 12, 2010 Sep 1, 2010 天津泰普药品科技发展有限公司 Method for preparing tolvaptan intermediate
WO2007026971A2 Sep 1, 2006 Mar 8, 2007 Otsuka Pharma Co Ltd Process for preparing benzazepine compounds or salts thereof
Reference
1   Cordero-Vargas, Alejandro
2   Kondo, Kazumi et al.7-chloro-5-hydroxy-1-[2-methyl-4-(2-methylbenzoyl-amino)benzoyl]-2,3,4,5-tetrahydro-1H-1-benzazepine (OPC-41061): A potent, orally active nonpeptide arginine vasopressin V2 receptor antagonist.《Bioorganic & Medicinal Chemistry》.1999,1743-1757.
3   Quiclet-Sire, Beatrice
4   Torisawa, Yasuhiro et al.Aminocarbonylation route to tolvaptan.《Bioorganic & Medicinal Chemistry Letters》.2007,6455-6458.
5   Zard, Samir Z.A flexible approach for the preparation of substituted benzazepines: Application to the synthesis of tolvaptan.《Bioorganic & Medicinal Chemistry》.2006,6165-6173.

///////////////

CC1=CC=CC=C1C(=O)NC2=CC(=C(C=C2)C(=O)N3CCCC(C4=C3C=CC(=C4)Cl)OP(=O)([O-])[O-])C.[Na+].[Na+]

////////////UPDATE 2022

Tolvaptan
(RS)-Tolvaptan Structural Formula V1.svg
Tolvaptan ball-and-stick model.png
Clinical data
Trade names Samsca, Jinarc, Jynarque, others
Other names OPC-41061
AHFS/Drugs.com Monograph
MedlinePlus a609033
License data
Pregnancy
category
  • UK: Contraindicated
Routes of
administration
By mouth
ATC code
Legal status
Legal status
Pharmacokinetic data
Bioavailability Unknown (40% absorbed)
Protein binding 99%
Metabolism Liver (CYP3A4-mediated)[7]
Elimination half-life 12 hours (terminal)
Identifiers
CAS Number
PubChem CID
IUPHAR/BPS
DrugBank
ChemSpider
UNII
KEGG
ChEMBL
CompTox Dashboard (EPA)
ECHA InfoCard 100.219.212 Edit this at Wikidata
Chemical and physical data
Formula C26H25ClN2O3
Molar mass 448.95 g·mol−1
3D model (JSmol)
 ☒check (what is this?)  (verify)

Tolvaptan, sold under the brand name Samsca among others, is an aquaretic drug that functions as a selective, competitive vasopressin receptor 2 (V2) antagonist used to treat hyponatremia (low blood sodium levels) associated with congestive heart failurecirrhosis, and the syndrome of inappropriate antidiuretic hormone (SIADH). Tolvaptan was approved by the U.S. Food and Drug Administration (FDA) on May 19, 2009, and is sold by Otsuka Pharmaceutical Co. under the trade name Samsca.[8] Tolvaptan, as Jynarque, was granted approval for medical use in the United States in April 2018.[9]

The U.S. Food and Drug Administration (FDA) granted tolvaptan a fast track designation for clinical trials investigating its use for the treatment of polycystic kidney disease.[10] The FDA granted Jynarque an orphan drug designation in April 2012, for the treatment of autosomal dominant polycystic kidney disease.[11]

Tolvaptan is available as a generic medication.[12]

Medical uses

Tolvaptan (Samsca) is indicated for the treatment of clinically significant hypervolemic and euvolemic hyponatremia.[13]

Tolvaptan (Jynarque) is indicated to slow kidney function decline in adults at risk of rapidly progressing autosomal dominant polycystic kidney disease (ADPKD).[14]

Side effects

The FDA has determined that tolvaptan should not be used for longer than 30 days and should not be used in patients with underlying liver disease because it can cause liver injury, potentially leading to liver failure.[15] When using to treat hyponatremia, it may cause too rapid correction of hyponatremia resulting in fatal osmotic demyelination syndrome.[16]

Pharmacology

Tolvaptan is a selective vasopressin V2 receptor antagonist.[13][14]

Chemistry

Tolvaptan is a racemate, a 1:1 mixture of the following two enantiomers:[17]

Enantiomers of tolvaptan
(R)-Tolvaptan Structural Formula V1.svg
(R)-Tolvaptan
CAS number: 331947-66-1
(S)-Tolvaptan Structural Formula V1.svg
(S)-Tolvaptan
CAS number: 331947-44-5

References

  1. ^ “Samsca 15 mg tablets – Summary of Product Characteristics (SmPC)”(emc). Retrieved 14 December 2020.
  2. ^ “Jinarc 15 mg tablets – Summary of Product Characteristics (SmPC)”(emc). 21 April 2020. Retrieved 14 December 2020.
  3. ^ “Jynarque- tolvaptan kit Jynarque- tolvaptan tablet”DailyMed. 31 March 2020. Retrieved 14 December 2020.
  4. ^ “Samsca- tolvaptan tablet”DailyMed. 26 October 2020. Retrieved 14 December 2020.
  5. ^ “Samsca EPAR”European Medicines Agency (EMA). Retrieved 14 December 2020.
  6. ^ “Jinarc EPAR”European Medicines Agency (EMA). Retrieved 14 December 2020.
  7. ^ Shoaf S, Elizari M, Wang Z, et al. (2005). “Tolvaptan administration does not affect steady state amiodarone concentrations in patients with cardiac arrhythmias”. J Cardiovasc Pharmacol Ther10 (3): 165–71. doi:10.1177/107424840501000304PMID 16211205S2CID 39158242.
  8. ^ “Drug Approval Package: Samsca (Tolvaptan) Tablets NDA #022275”U.S. Food and Drug Administration (FDA). 21 July 2009. Retrieved 15 August 2020Lay summary (PDF). {{cite web}}Cite uses deprecated parameter |lay-url= (help)
  9. ^ “Drug Approval Package: Jynarque (tolvaptan)”U.S. Food and Drug Administration (FDA). 8 June 2018. Retrieved 15 August 2020.
  10. ^ “Otsuka Maryland Research Institute, Inc. Granted Fast Track Designation For Tolvaptan In PKD”Medical News Today. Healthline Media UK Ltd. Retrieved 6 December 2018.
  11. ^ “Tolvaptan Orphan Drug Designations and Approvals”U.S. Food and Drug Administration (FDA). 6 April 2012. Retrieved 15 August 2020.
  12. ^ “Drugs@FDA: FDA-Approved Drugs”U.S. Food and Drug Administration (FDA). Retrieved 15 August 2020.
  13. Jump up to:a b “Samsca- tolvaptan tablet”DailyMed. 28 May 2019. Retrieved 15 August 2020.
  14. Jump up to:a b “Jynarque- tolvaptan kit Jynarque- tolvaptan tablet”DailyMed. 31 March 2020. Retrieved 15 August 2020.
  15. ^ “U.S. Food and Drug Administration.” Samsca (Tolvaptan): Drug Safety Communication. N.p., 30 Apr. 2013. Web. 1 June 2014. <http://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm350185.htm>[dead link]
  16. ^ Goodman & Gilman’s the pharmacological basis of therapeutics. Brunton, Laurence L, Knollmann, Björn C, Hilal-Dandan, Randa (Thirteenth ed.). New York. 5 December 2017. ISBN 9781259584732OCLC 994570810.
  17. ^ Rote Liste Service GmbH (Hrsg.): Rote Liste 2017 – Arzneimittelverzeichnis für Deutschland (einschließlich EU-Zulassungen und bestimmter Medizinprodukte). Rote Liste Service GmbH, Frankfurt/Main, 2017, Aufl. 57, ISBN 978-3-946057-10-9, S. 222.

Further reading

External links

  • “Tolvaptan”Drug Information Portal. U.S. National Library of Medicine.

Synthesis

Synthesis of Tolvaptan
Fugure 1: Synthesis of Tolvaptan

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Title: Tolvaptan

CAS Registry Number: 150683-30-0

CAS Name: N-[4-[(7-Chloro-2,3,4,5-tetrahydro-5-hydroxy-1H-1-benzazepin-1-yl)carbonyl]-3-methylphenyl]-2-methylbenzamide

Additional Names: 7-chloro-5-hydroxy-1-[2-methyl-4-(2-methylbenzoylamino)benzoyl]-2,3,4,5-tetrahydro-1H-1-benzazepine

Manufacturers’ Codes: OPC-41061

Molecular Formula: C26H25ClN2O3

Molecular Weight: 448.94

Percent Composition: C 69.56%, H 5.61%, Cl 7.90%, N 6.24%, O 10.69%

Literature References: Nonpeptide arginine vasopressin V2 receptor antagonist. Prepn: H. Ogawa et al., WO 9105549eidemUS 5258510 (1991, 1993 both to Otsuka); K. Kondo et al., Bioorg. Med. Chem. 7, 1743 (1999). Pharmacology: Y. Yamamura et al., J. Pharmacol. Exp. Ther. 287, 860 (1998). Clinical trial in heart failure: M. Gheorghiade et al., J. Am. Med. Assoc. 291, 1963 (2004).

Properties: Colorless prisms, mp 225.9°.

Melting point: mp 225.9°

Therap-Cat: In treatment of congestive heart failure.

Keywords: Vasopressin Receptor Antagonist.

Medicinal Chemistry International: DELDEPREVIR (NECEPREVIR)


Medicinal Chemistry International: DELDEPREVIR (NECEPREVIR)

WANT TO KNOW ABOUT VIR SERIES CLICK

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DELDEPREVIR OR NECEPREVIR

Figure US20100152103A1-20100617-C00127
ACH-0142684, ACH-2684
HCV NS3 PR
USAN (YY-152) DELDEPREVIR
THERAPEUTIC CLAIM Treatment of Hepatitis C
CHEMICAL NAMES
1. Cyclopropa[e]pyrrolo[1,2-a][1,4]diazacyclopentadecine-14a(5H)-carboxamide, N-
(cyclopropylsulfonyl)-6-[2-(3,3-difluoro-1-piperidinyl)-2-oxoethyl]-
1,2,3,6,7,8,9,10,11,13a,14,15,16,16a-tetradecahydro-2-[[7-methoxy-8-methyl-2-[4-(1-
methylethyl)-2-thiazolyl]-4-quinolinyl]oxy]-5,16-dioxo-, (2R,6R,12Z,13aS,14aR,16aS)-
2. (2R,6R,12Z,13aS,14aR,16aS)-N-(cyclopropylsulfonyl)-6-[2-(3,3-difluoropiperidin-1-yl)-
2-oxoethyl]-2-({7-methoxy-8-methyl-2-[4-(1-methylethyl)thiazol-2-yl]quinolin-4-yl}oxy)-
5,16-dioxo-1,2,3,6,7,8,9,10,11,13a,14,15,16,16atetradecahydrocyclopropa[e]pyrrolo[1,2-a][1,4]diazacyclopentadecine-14a(5H)-
carboxamide
MOLECULAR FORMULA C45H56F2N6O8S2
MOLECULAR WEIGHT 911.1
SPONSOR Achillion Pharmaceuticals, Inc.
CODE DESIGNATION ACH-0142684, ACH-2684
CAS REGISTRY NUMBER 1229626-28-1
WHO NUMBER 9600
NOTE: This adoption statement replaces adoption N12/17 and the name neceprevir is hereby rescinded.
……………………………………………………………………………………………………….
DELDEPREVIR SODIUM
USAN (yy-153) DELDEPREVIR SODIUM
THERAPEUTIC CLAIM Treatment of Hepatitis C
CHEMICAL NAMES
1. Cyclopropa[e]pyrrolo[1,2-a][1,4]diazacyclopentadecine-14a(5H)-carboxamide, N-
(cyclopropylsulfonyl)-6-[2-(3,3-difluoro-1-piperidinyl)-2-oxoethyl]-
1,2,3,6,7,8,9,10,11,13a,14,15,16,16a-tetradecahydro-2-[[7-methoxy-8-methyl-2-[4-(1-
methylethyl)-2-thiazolyl]-4-quinolinyl]oxy]-5,16-dioxo-, sodium salt (1:1),
(2R,6R,12Z,13aS,14aR,16aS)-
2. Sodium (cyclopropylsulfonyl){[(2R,6R,12Z,13aS,14aR,16aS)-6-[2-(3,3-difluoropiperidin-
1-yl)-2-oxoethyl]-2-({7-methoxy-8-methyl-2-[4-(1-methylethyl)thiazol-2-yl]quinolin-4-
yl}oxy)-5,16-dioxo-1,2,3,6,7,8,9,10,11,13a,14,15,16,16a-
tetradecahydrocyclopropa[e]pyrrolo[1,2-a][1,4]diazacyclopentadecin-14a(5H)-
yl]formyl]azanide
MOLECULAR FORMULA C45H55F2N6NaO8S2
MOLECULAR WEIGHT 933.1
SPONSOR Achillion Pharmaceuticals, Inc.
CODE DESIGNATION ACH-0142684.Na, ACH-2684.Na
CAS REGISTRY NUMBER 1298053-61-8
NOTE: This adoption statement replaces adoption N12/18 and the name neceprevir sodium
is hereby rescinded.
ACH-2684 is a HCV NS3 protease inhibitor in phase I clinical development at Achillion for the oral treatment of chronic hepatitis C genotype 1 and 3.
WO 2010068761
US 2010152103
Figure US20100152103A1-20100617-C00127
COMPD 133
(2R,6R,14aR,16aS,Z)- N-(cyclopropylsulfonyl)- 6-(2-(3,3-difluoropiperidin- 1-yl)-2-oxoethyl)-2- (2-(2-isopropylthiazol- 4-yl)-7-methoxy-8- methylquinolin-4- yloxy)-5,16-dioxo- 1,2,3,5,6,7,8,9,10,11, 13a,14,14a,15,16,16a- hexadecahydrocyclopropa [e]pyrrolo[1,2- a][1,4] diazacyclopentadecine- 14a-carboxamide

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Deleobuvir » All About Drugs


Deleobuvir » All About Drugs

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DELEOBUVIR

DELEOBUVIR
(2E)-3-(2-{1-[2-(5-Bromopyrimidin-2-yl)-3-cyclopentyl-1-methyl-1H-indole-6-carboxamido]cyclobutyl}-1-methyl-1H-benzimidazol- 6-yl)prop-2-enoic acid
1221574-24-8 CAS  please check may be sodium salt??
cas no  as per below ref ……863884-77-9 (free acid)
PHASE 3
BI-207127NA
BI-207127 (free acid)
BI-207127 is a novel HCV RNA polymerase inhibitor in phase III clinical development at Boehringer Ingelheim for the treatment of hepatitis C.
Company Boehringer Ingelheim GmbH
Description Oral non-structural protein 5B (NS5B) RNA-dependent polymerase inhibitor
Molecular Target HCV NS5B polymerase 
Mechanism of Action Viral polymerase inhibitor
Therapeutic Modality Small molecule
Latest Stage of Development Phase III
Indication Hepatitis C virus (HCV)
Partner
Deleobuvir (formerly BI 207127) is an experimental drug for the treatment of hepatitis C. It is being developed by Boehringer-Ingelheimand is currently in Phase II trials. It is a non-nucleoside hepatitis C virus NS5B polymerase inhibitor. Deleobuvir is being tested in combination regimens with pegylated interferon and ribavirin, and in interferon-free regimens with other direct-acting antiviral agents including faldaprevir.
Data from the SOUND-C2 study, presented at the 2012 AASLD Liver Meeting, showed that a triple combination of deleobuvir, faldaprevir, and ribavirin performed well in HCV genotype 1b patients.[1] Efficacy fell below 50%, however, for dual regimens without ribavirin and for genotype 1a patients.Deleobuvir (BI 207127) is an investigational oral nonnucleoside inhibitor of hepatitis C virus (HCV) NS5B RNA polymerase. Antiviral activity, virology, pharmacokinetics, and safety were assessed in HCV genotype 1-infected patients receiving 5 days’ deleobuvir monotherapy. In this double-blind phase 1b study, treatment-naive (TN; n = 15) and treatment-experienced (TE; n = 45) patients without cirrhosis received placebo or deleobuvir at 100, 200, 400, 800, or 1,200 mg every 8 h (q8h) for 5 days. Patients with cirrhosis (n = 13) received deleobuvir at 400 or 600 mg q8h for 5 days. Virologic analyses included NS5B genotyping and phenotyping of individual isolates. At day 5, patients without cirrhosis had dose-dependent median HCV RNA reductions of up to 3.8 log10 (with no placebo response); patients with cirrhosis had median HCV RNA reductions of approximately 3.0 log10. Three patients discontinued due to adverse events (AEs). The most common AEs were gastrointestinal, nervous system, and skin/cutaneous tissue disorders. Plasma exposure of deleobuvir was supraproportional at doses ≥ 400 mg q8h and approximately 2-fold higher in patients with cirrhosis than in patients without cirrhosis. No virologic breakthrough was observed. NS5B substitutions associated with deleobuvir resistance in vitro were detected in 9/59 patients; seven encoded P495 substitutions, including P495L, which conferred 120- to 310-fold-decreased sensitivity to deleobuvir. P495 variants did not persist in follow-up without selective drug pressure. Deleobuvir monotherapy was generally well tolerated and demonstrated dose-dependent antiviral activity against HCV genotype 1 over 5 days.
These results were confirmed in the SOUND-C3 study, presented at the 2013 APASL Liver Conference, which found that 16 week triple therapy with deleobuvir + faldaprevir + ribavirin gave 95% SVR12 in HCV genotype 1b patients but poor virological response in genotype 1a.[2]

  1.  Interferon-free hepatitis C treatment with faldaprevir proves safe and effective in people with cirrhosis. Alcorn, K. Aidsmap.com. 20 November 2012.
  2.  S Zeuzem, J-F Dufour, M Buti, V Soriano, R Buynak, P Mantry, J Taunk, JO Stern, R Vinisko, J-P Gallivan, WO Bocher and FJ Mensa.“Interferon-free treatment with faldaprevir, deleobuvir (BI 207127) and ribavirin in SOUND-C3: 95% SVR12 in HCV GT-1b”23rd Conference of the Asian Pacific Association for the Study of the Liver (APASL) 6–9 June 2013. Retrieved 12 Sep 2013.
PATENTS
WO 2013147750
 WO 2013147749
WO 2012041771
WO 2012044520
WO 2012016995
WO 2005080388
……………………………………………………
PATENT
Patent Filing date Publication date Applicant Title
WO2010059667A1 Nov 18, 2009 May 27, 2010 Boehringer Ingelheim International Gmbh Pharmaceutical composition of a potent hcv inhibitor for oral administration
WO2011005646A2 Jul 1, 2010 Jan 13, 2011 Boehringer Ingelheim International Gmbh Pharmaceutical composition for a hepatitis c viral protease inhibitor
WO2012041771A1 * Sep 23, 2011 Apr 5, 2012 Boehringer Ingelheim International Gmbh Combination therapy for treating hcv infection
US4211771 Feb 13, 1978 Jul 8, 1980 Robins Ronald K Treatment of human viral diseases with 1-B-D-ribofuranosyl-1,2,4-triazole-3-carboxamide
US6063772 Jun 15, 1998 May 16, 2000 Icn Pharmaceuticals, Inc. Specific modulation of Th1/Th2 cytokine expression by ribavirin in activated T-lymphocytes
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2 BERG ET AL. HEPATOL vol. 52, no. S1, 2010,
3 * DOMINIQUE LARREY ET AL: “Rapid and strong antiviral activity of the non-nucleosidic NS5B polymerase inhibitor BI 207127 in combination with peginterferon alfa 2a and ribavirin“, JOURNAL OF HEPATOLOGY, vol. 57, no. 1, 7 March 2012 (2012-03-07), pages 39-46, XP55040240, ISSN: 0168-8278, DOI: 10.1016/j.jhep.2012.02.015
4 G. CAIRNS GENE VARIANT THAT HELPS HEPATITIS C TREATMENT MAY HINDER HIV TREATMENT, [Online] 2011, Retrieved from the Internet: <URL:http://www.bhiva.org/Ncws.aspx?NewsID=a7503829-94b9-4d2f-bd91-ld2fbaad6c8d&gt;
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6 GHANY; MARC ET AL.: ‘An Update on Treatment of Genotype 1 Chronic Hepatitis C Virus Infection: 2011 Practice Guideline by the American Association for the Study of Liver Diseases‘ HEPATOLOGY vol. 54, no. 4, 2011, pages 1433 – 44
7 * LIZ HIGHLEYMAN: “AASLD: All-Oral Combination of BI 201335, BI 207127 and Ribavirin Shows Good Efficacy at 12 Weeks“, INTERNET CITATION, [Online] 1 December 2011 (2011-12-01), pages 1-3, XP002684260, Retrieved from the Internet: URL:www.hivandhepatitis.com/hepatitis-c/he patitis-c-topics/hcv-treatment/3371-aasld- all-oral-combination-of-bi-201335-bi-20712 7-and-ribavirin-shows-good-efficacy-at-12- weeks> [retrieved on 2012-09-27]
8 * POL S ET AL: “SVR AND PHARMACOKINETICS OF THE HCV PROTEASE INHIBITOR BI201335 WITH PEGIFN/RBV IN HCV GENOTYPE-1 PATIENTS WITH COMPENSATED LIVER CIRRHOSIS AND NON-RESPONSE TO PREVIOUS PEGIFN/RBV“, JOURNAL OF HEPATOLOGY, vol. 54, no. Suppl. 1, March 2011 (2011-03), page S486, XP55038942, & 46TH ANNUAL MEETING OF THE EUROPEAN-ASSOCIATION-FOR-THE-STUDY-OF-THE- LIVER (EASL); BERLIN, GERMANY; MARCH 30 -APRIL 03, 2011 ISSN: 0168-8278
9 S. M. BIRGE ET AL. J. PHARM. SCI. vol. 66, 1977, pages 1 – 19
10 * STEFAN ZEUZEM ET AL: “Efficacy of the Protease Inhibitor BI 201335, Polymerase Inhibitor BI 207127, and Ribavirin in Patients With Chronic HCV Infection“, GASTROENTEROLOGY, ELSEVIER, PHILADELPHIA, PA, vol. 141, no. 6, 1 December 2011 (2011-12-01), pages 2047-2055, XP002664706, ISSN: 0016-5085, DOI: 10.1053/J.GASTRO.2011.08.051
11 SULKOWSKI MS ET AL. HEPATOL vol. 50, 2009, page 2A
12 SULKOWSKI MS ET AL. J HEPATOL vol. 52, no. 1, 2010, pages S462 – S463
13 WHITE PW ET AL. ANTIMICROB AGENTS CHEMOTHER vol. 54, no. 11, 2010, pages 4611 – 4618
14 WHO COLLABORATIVE STUDY GROUP. VOX SANG vol. 76, 1999, pages 149 – 158
15 * ZEUZEM STEFAN ET AL: “STRONG ANTIVIRAL ACTIVITY AND SAFETY OF IFN-SPARING TREATMENT WITH THE PROTEASE INHIBITOR BI 201335, THE HCV POLYMERASE INHIBITOR BI 207127 AND RIBAVIRIN IN PATIENTS WITH CHRONIC HEPATITIS C“, HEPATOLOGY, WILLIAMS AND WILKINS, BALTIMORE, MD, US, vol. 52, no. Suppl, 1 October 2010 (2010-10-01), pages 876A-877A, XP009154421, ISSN: 0270-9139
16 * ZEUZEM STEFAN ET AL: “VIROLOGIC RESPONSE TO AN INTERFERON-FREE REGIMEN OF BI201335 AND BI207127, WITH AND WITHOUT RIBAVIRIN, IN TREATMENT-NAIVE PATIENTS WITH CHRONIC GENOTYPE-1 HCV INFECTION: WEEK 12 INTERIM RESULTS OF THE SOUND-C2 STUDY“, HEPATOLOGY, WILLIAMS AND WILKINS, BALTIMORE, MD, US, vol. 54, no. Suppl. 1, 1 November 2011 (2011-11-01), page 1436A, XP009163087, ISSN: 0270-9139, DOI: 10.1002/HEP.24666 [retrieved on 2011-09-30]
…………………………………………………………
The following……
Figure imgf000004_0001
having the chemical name: (E)-3-[2-(l-{ [2-(5-Bromo-pyrimidin-2-yl)-3-cyclopentyl-l- methyl-lH-indole-6-carbonyl]-amino}-cyclobutyl)-3-methyl-3H-benzimidazol-5-yl]- acrylic acid, is known as a selective and potent inhibitor of the HCV NS5B RNA- dependent RNA polymerase and useful in the treatment of HCV infection. Compound (2) falls within the scope of HCV inhibitors disclosed in U.S. Patents 7,141,574 and
7,582,770, and US Application Publication 2009/0087409. Compound (2) is disclosed specifically as Compound # 3085 in U.S. Patent 7,582,770. Compound (2), and pharmaceutical formulations thereof, can be prepared according to the general procedures found in the above-cited references, all of which are herein incorporated by reference in their entirety. Preferred forms of Compound (2) include the crystalline forms, in particular the crystalline sodium salt form which is prepared as herein described.
It is known in the art that particular HCV subtypes and patient subgenotypes may respond differently to HCV therapy. HCV Genotype la is traditionally more difficult to treat and are less responsive to antiviral therapy than Genotype lb. See, e.g., Ghany, Marc et al. “An Update on Treatment of Genotype 1 Chronic Hepatitis C Virus Infection: 2011 Practice Guideline by the American Association for the Study of Liver Diseases”, Case No.: 09-0592-PCT
Hepatology, 54(4): 1433-44 (2011)). In addition, and particularly with interferon-based therapy, specific single nucleotide polymorphisms (SNPs) located on the long arm of chromosome 19 within the gene cluster of IL-28B (Interleukin (IL) 28B, (also called lambda interferon), of the patient undergoing therapy can directly effect the
responsiveness of that patient to the antiviral therapy. In particular, patients having a non- CC genotype of SNP rsl2979860 or a non-TT genotype of rs 8099917 are traditionally more difficult to treat and are less responsive in terms of a sustained virological response (SVR) than patients having the CC or TT genotype.. The SNP that was most strongly associated with SVR in the genome-wide analysis was rs 12979860 followed by rs 8099917. See, e.g., Ge et al., Nature, 461 :399-401 (2009) and Balagopal,
Gastroenterology, 139: 1865-1876 (2010). See G. Cairns, “Gene variant that helps hepatitis C treatment may hinder HIV treatment”, 2011, at:
http://www.bhiva.org^ Thus, there is a need in the art for therapies that are effective against even the more difficult-to-treat patient subpopulations, particularly those exhibiting HCV subtype la and the non-CC IL28B subgenotype, as well as those exhibiting compensated liver disease.
Examples
I. Methods for Preparing Compound (1)
Methods for preparing amorphous Compound (1) and a general description of
pharmaceutically acceptable salt forms can be found in US Patents 6,323,180, 7,514,557 and 7,585,845. Methods for preparing additional forms of Compound (1), in particular the crystalline sodium salt form, can be found in U.S. Patent Application Publication No. 2010/0093792.
II. Formulations of Compound (1) Case No. : 09-0592-PCT
One example of a pharmaceutical formulation of Compound (1) include an oral solution formulation as disclosed in WO 2010/059667. Additional examples include capsules containing a lipid-based liquid formulation, as disclosed in WO 201 1/005646. III. Methods for Preparing Compound (2)
Methods for preparing amorphous Compound (2) can be found in U.S. Patents 7, 141 ,574 and 7,582,770, and US Application Publication 2009/0087409.
The following Example provides the method for preparing an additional form of
Compound (2), the sodium salt form, that may be used in the present invention.
Example 1 – Preparation of Compound (2) Sodium Salt
Step 1. Synthesis of Isopropyl 3-Cyclopentyl-l-methyl-lH-indole-6-carboxylate
Figure imgf000024_0001
Because of the instability of brominated product, methyl 3 -cyclopentyl- 1 -methyl- 1Η- indole-6-carboxylate needed to be converted into the more stable isopropyl 3-cyclopentyl- l-methyl- lH-indole-6-carboxylate via a simple and high yielding operation. The conversion worked the best with stoichiometric amounts of solid lithium isopropoxide. Use of 0.1 eq lithium isopropoxide led to longer reaction times and as a result to more hydrolysis by-product, while lithium isopropoxide solution in THF caused a problematic isolation and required distillation of THF.
Procedure: Case No.: 09-0592-PCT
The mixture of methyl 3 -cyclopentyl- 1 -methyl- lH-indole-6-carboxylate (50.0 g, 0.194 mol) and lithium isopropoxide (16.2 g, 95%, 0.233 mol) in 2-propanol was stirred at 65+5 °C for at least 30 min for complete trans-esterification. The batch was cooled to 40+5 °C and water (600 g) was added at a rate to maintain the batch temperature at 40+5°C. After addition, the mixture was cooled to 20-25 °C over 2+0.5 h and held at 20-25 °C for at least 1 h. The batch was filtered and rinsed with 28 wt% 2-propanol in water (186 g), and water (500 g). The wet cake was dried in vacuo (< 200 Torr) at 40-45 °C until the water content was < 0.5% to give isopropyl 3-cyclopentyl-l-methyl-lH-indole-6-carboxylate (52.7 g, 95% yield) in 99.2 A% (240 nm).
The starting material methyl 3-cyclopentyl-l-methyl-lH-indole-6-carboxylate can be prepared as described in Example 12 of U.S. Patent 7,141,574, and in Example 12 of U.S. Patent 7,642,352, both herein incorporated by reference.
Step 2. Synthesis of Isopropyl 2-Bromo-3-cyclopentyl-l-methyl-lH-indole-6- carboxylate
Figure imgf000025_0001
This process identified the optimal conditions for the synthesis of 2-bromo-3-cyclopentyl- l-methyl-lH-indole-6-carboxylate via bromination of the corresponding 3 -cyclopentyl- 1- methyl-lH-indole-6-carboxylate with bromine. It’s very important to control the reaction temperature and to quench the reaction mixture with a mixture of aqueous sodium thiosulfate and 4-methylmorpholine to minimize the formation of the dibromo- and 2- indolone impurities. Further neutralization of the crude product with NaOH in isopropanol greatly increases the stability of the isolated product. Case No.: 09-0592-PCT
Procedure:
The mixture of isopropyl 3-cyclopentyl-l-methyl-lH-indole-6-carboxylate (50.0 g, 0.175 mol) and acetonitrile (393 g) was cooled to -6+3 °C. Bromine (33.6 g, 0.210 mol) was added while the batch was maintained at -6+3°C. The resulting slurry was stirred at – 6+3°C for at least 30 min. When HPLC showed > 94 % conversion (the HPLC sample must be quenched immediately with aqueous 4-methylmorpholine/sodium thiosulfate solution), the mixture was quenched with a solution of sodium thiosulfate (15.3 g) and 28.4 g 4-methylmorpholine in water (440 g) while the temperature was maintained at -5+5 °C. After it was stirred at 0+5 °C for at least 2 h, the batch was filtered and rinsed with 85 wt methanol/water solution (415 g), followed by water (500 g), and dried until water content is < 30%. The wet cake was suspended in 2-propanol (675 g), and heated to 75+5 °C. The resulting hazy solution was treated with 1.0 M aqueous sodium hydroxide solution (9.1 g) and then with 135.0 g water at a rate to maintain the batch at 75+5°C. The suspension was stirred at 75+5°C for at least 30 min, cooled to 15+2 °C over 30-40 min, and held at 15+2 °C for at least 1 h. The batch was filtered, rinsed with 75 wt% 2-propanol/water solution (161 g), and dried in vacuo (<200 Torr) at 50-60 °C until the water content was < 0.4% to give isopropyl 2-bromo-3-cyclopentyl-l -methyl- lH-indole-6-carboxylate as a solid (55.6 g, 87 % yield ) in 99.5 A% (240 nm) and 97.9 Wt%. Alternative Procedure:
The mixture of isopropyl 3-cyclopentyl-l-methyl-lH-indole-6-carboxylate (84 g, 0.294 mol) and isopropyl acetate (1074 g) was cooled to between -10-0 °C. Bromine (50 g, 0.312 mol) was added while the batch was maintained at -10 – 0 °C. The resulting slurry was stirred at the same temperature for additional 30 min and quenched with a pre-cooled solution of sodium thiosulfate pentahydrate (13 g) and triethylamine (64.5 g) in water (240 g) while the temperature was maintained at 0-10 °C. The mixture was heated to 40 – 50 °C and charged with methanol (664 g). After it was stirred at the same temperature for at least 0.5 h, the batch was cooled to 0 – 10 °C and stirred for another 1 hr. The precipitate was filtered, rinsed with 56 wt% methanol/water solution (322 g), and dried in vacuo (<200 Case No. : 09-0592-PCT
Torr) at 50-60 °C until the water content was < 0.4% to give isopropyl 2-bromo-3- cyclopentyl-l -methyl- lH-indole-6-carboxylate as a beige solid (90-95 g, 80-85 % yield ).
Step 3a,b. Preparation of compound I by one-pot Pd-catalyzed borylation- Suzuki coupling reaction
Figure imgf000027_0001
To a clean and dry reactor containing 20.04 g of isopropyl 2-bromo-3-cyclopentyl- l- methyl- lH-indole-6-carboxylate, 1.06 g of Pd(TFP)2Cl2(3 mol%) and 0.76 g of tri(2- furyl)phosphine (6 mol%) was charged 8.35 g of triethylamine (1.5 equivalent), 39.38 g of CH3CN at 23+10 °C under nitrogen or argon and started agitation for 10 min. 9.24 g of 4,4,5, 5-tetramethyl-l ,3,2-dioxaborolane was charged into the reactor. The mixture was heated to reflux (ca. 81 -83 °C) and stirred for 6h until the reaction completed. The batch was cooled to 30+5 °C and quenched with a mixture of 0.99 g of water in 7.86 g of
CH3CN. 17.24 g of 5-bromo-2-iodopyrimidine and 166.7 g of degassed aqueous potassium phosphate solution (pre-prepared from 46.70 g of K3PO4 and 120 g of H20) was charged subsquently under argon or nitrogen. The content was heated to reflux (ca. 76-77 °C) for 2 h until the reaction completed. 4.5 g of 1-methylimidazole was charged into the reactor at 70 °C. The batch was cooled to 20+3 °C over 0.5h and hold at 20+3 °C for at least lh. The solid was collected by filtration. The wet cake was first rinsed with 62.8 g of 2-propanol, Case No. : 09-0592-PCT
followed by 200 g of H20. The solid was dried under vacuum at the temperature below 50 °C.
Into a dry and clean reactor was charged dried I, 10 wt Norit SX Ultra and 5 V of THF. The content was heated at 60+5 °C for at least 1 h. After the content was cooled to 35+5 °C, the carbon was filtered off and rinsed with 3 V of THF. The filtrate was charged into a clean reactor containing 1-methylimidazole (10 wt % relative to I). After removal of 5 V of THF by distillation, the content was then cooled to 31 ±2 °C. After the agitation rate was adjusted to over 120 rpm, 2.5 V of water was charged over a period of at least 40 minutes while maintaining the content temperature at 31 + 2 °C. After the content was agitated at 31 + 2 °C for additional 20 min, 9.5 V of water was charged into the reactor over a period of at least 30 minutes at 31 + 2 °C. The batch was then cooled to about 25 + 3 °C and stirred for additional 30 minutes. The solid was collected and rinsed with 3 V of water. The wet product I was dried under vacuum at the temperature below 50 °C (19.5 g, 95 wt , 76% yield).
Alternative Procedure:
To a clean and dry reactor containing 40 g of isopropyl 2-bromo-3-cyclopentyl- l-methyl- lH-indole-6-carboxylate (0.1 10 mol), 0.74 g of Pd(OAc)2 (3.30 mmol, 3 mol% equiv.) and 3.2 g of tri(2-furyl)phosphine (13.78 mmol, 12.5 mol% equiv.) was charged 16.8 g of triethylamine (1.5 equivalent), 100 mL of acetonitrile at 25 °C under nitrogen or argon. 20.8 g of 4,4,5, 5-tetramethyl- l ,3,2-dioxaborolane was charged into the reactor within 30 min. The mixture was heated to reflux (ca. 81 -83 °C) and stirred for over 5 hrs until the reaction completed. The batch was cooled to 20 °C and quenched with a mixture of 2.7 g of water in 50 mL of CH3CN. The batch was warmed to 30 °C, stirred for 1 hr and transferred to a second reactor containing 34.4 g of 5-bromo-2-iodopyrimidine in 100 mL of acetonitrile. The reactor was rinsed with 90 mL of acetonitrile. To the second reactor was charged with degassed aqueous potassium phosphate solution (pre-prepared from 93.2 g of K3PO4 and 100 g of H20) under argon or nitrogen. The content was heated to reflux (ca. 80 °C) for over 3 h until the reaction completed. 9.2 g of 1 -methylimidazole was charged into the reactor at 70 °C and the mixture was stirred for at least 10 min. The aqueous phase was removed after phase separation. 257 g of isopropanol was charged at 70 Case No.: 09-0592-PCT
°C. The batch was cooled slowly to 0 °C and hold for at least 1 h. The solid was collected by filtration. The wet cake was rinsed twice with 2-propanol (2 x 164 g) and dried under vacuum at the temperature below 50 °C to give I as a yellow to brown solid (26 g, 75% yield).
Step 4. Hydrolysis of I to II
Figure imgf000029_0001
I (20 g) and l-methyl-2-pyrrolidinone (NMP) (113 g) were charged into a clean reactor under nitrogen. After the batch was heated to 50-53 °C with agitation, premixed aq. NaOH (5.4 g of 50% aq. NaOH and 14.3 g of water) was introduced into the reactor. The resulting mixture was stirred at 50-53 °C for about 10 hrs until the reaction completed. A premixed aq. HOAc (60 g of water and 9.0 g of HOAc) was added over 0.5 h at 45 ±5 °C to reach pH 5.5- 7.5. The batch was cooled to 20+5 °C and then kept for at least 1.0 h. The solid product was collected and rinsed with 80 g of NMP/water (1 :3 volume ratio) and then 60 g of water. The product was dried under vacuum at the temperature below 50 °C to give II as a pale yellow powder (19 -20 g, purity > 99.0 A% and 88.4 wt%, containing 5.4 wt% NMP). The yield is about 93-98%.
Notes: The original procedure used for the hydrolysis of I was carried out with aq. NaOH (2.5 eq) in MeOH/THF at 60 °C. Although it has been applied to the preparation of II on several hundred grams scale, one disadvantage of this method is the formation of 5-MeO pyrimidine during hydrolysis (ca. 0.4 A%), which is extremely difficult to remove in the subsequent steps. In addition, careful control has to be exerted during crystallization. Case No.: 09-0592-PCT
Otherwise, a thick slurry might form during acidification with HO Ac. The use of NMP as solvent could overcome all aforementioned issues and give the product with desired purity.
Alternative Process
To a reactor was charged I (71 g), isopropanol (332 g), aqueous NaOH (22 g, 45 wt ) and water (140 g) at ambient temperature. The mixture was heated to reflux (80 °C) and stirred for at least 3 hrs until the reaction completed. The batch was cooled to 70 °C and charged a suspension of charcoal (3.7 g) in isopropanol (31 g). The mixture was stirred at the same temperature for over 10 min and filtered. The residue was rinsed with isopropanol (154 g). Water (40 g) was charged to the filtrate at 70 – 80 °C, followed by slow addition of 36% HC1 solution (20 g) to reach pH 5- 6. The batch was stirred for over 30 min at 70 °C, then cooled to 20 °C over 1 hr and kept for at least 1.0 h. The solid product was collected and rinsed with 407 g of isopropanol/water (229 g IPA, 178 g H20). The product was dried under vacuum at 80 °C for over 5 hrs to give II as a white powder (61 g, 95% yield).
Notes on Steps 5 to 8 below:
A concise and scalable 4-step process for the preparation of the benzimidazole
intermediate V was developed. The first step was the preparation of 4-chloro-2-(methyl)- aminonitrobenzene starting from 2,4-dichloronitrobenzene using aqueous methyl amine in DMSO at 65 °C. Then, a ligandless Heck reaction with n-butyl acrylate in the presence of Pd(OAc)2, ‘PrzNEt, LiCl, and DMAc at 110 °C was discovered.
Step 5: SNAr reaction of (5-chloro-2-nitrophenyl)-methylamine
Figure imgf000030_0001
To a solution of (5-chloro-2-nitrophenyl)-methylamine (40 g, 208.3 mmol, 1 equiv) in DMSO (160 mL) was added 40% MeNH2solution in water (100 mL, 1145. 6 mmol, 5.5 eq) slowly keeping the temperature below 35 °C. The reaction was stirred at r.t. until the Case No.: 09-0592-PCT
complete consumption of the starting material (>10 h). Water (400 mL) was added to the resulting orange slurry and stirred at r.t. for additional 2 h. The solid was filtered, rinsed with water (200 mL) and dried under reduced pressure at 40 °C. (5-chloro-2-nitrophenyl)- methylamine (36.2 g, 93% yield, 94 A% purity) was isolated as a solid.
Step 6: Heck Reaction of (5-chloro-2-nitrophenyl)-methylamine
Figure imgf000031_0001
DMAc (5 vol), 1 10 °C, 7-22 h To a mixture of 4-chloro-2-methylaminonitrobenzene (50.0 g, 268.0 mmol, 1.0 eq),
Pd(OAc)2 (0.30 g, 1.3 mmol, 0.005 eq) and LiCI (11.4 g 268.0 mmol, 1.0 eq) in DMAc (250 mL) was added ‘Pr2NEt (56 mL, 321.5 mmol, 1.2 eq) followed by n-butyl acrylate (40 mL, 281.4 mmol, 1.05 eq) under nitrogen. The reaction mixture was stirred at 110 °C for 12 h, then cooled to 50 °C. 1 -methylimidazole (10.6 mL, 134.0 mmol, 0.5 eq) was added and the mixture was stirred for 30 min before filtering and adding water (250 mL). The resulting mixture was cooled to r.t. over 1 h. The resulting solid was filtered and washed with water and dried to yield n-butyl 3-methylamino-4-nitrocinnamate (71.8 g, 96 %, 99.2 A% purity).
Step 7: Reduction of n-butyl (3-methylamino-4-nitro)-cinnamate
Figure imgf000031_0002
III Case No.: 09-0592-PCT
To a reactor was charged n-butyl 3-methylamino-4-nitrocinnamate (70.0 g, mmol, 1.0 eq) , Raney Ni (4.9 g, ~20wt% H20), charcoal “Norit SX Ultra” (3.5 g), toluene (476 mL) and MeOH (224 mL). The reactor was charged with hydrogen (4 bar) and the mixture was stirred at 20- 25 °C for about 2 hrs until the reaction was completed. The reaction mixture was filtered and rinsed the filter residue with toluene (70 mL). To the combined filtrates were added “Norit SX Ultra” charcoal (3.5 g). The mixture was stirred at 50 °C for 1.0 hr and filtered. The filtrate was concentrated under reduced pressure to remove solvents to 50% of the original volume. The remained content was heated to 70 °C and charged slowly methyl cyclohexane (335 mL) at the same temperature. The mixture was cooled to about 30 – 40 °C and seeded with III seed crystals, then slowly cooled the suspension to— 10 °C. The solid was filtered and rinsed with methyl cyclohexane in three portions (3 x 46 mL). The wet cake was dried in vacuo at 40 °C to give III (53.3 g, 215 mmol, 86%).
Step 8: Preparation of benzimidazole V
DCC
Figure imgf000032_0001
To reactor-1 was charged III (35 g, 140.95 mmol) in toluene (140 g). The mixture was heated to 50 °C to obtain a clear solution. To a second reactor was charged IV (36.4 g, 169.10 mmol) and toluene (300 g), followed by addition of a solution of dicyclohexyl carbodimide (11.6 g, in 50% toluene, 28.11 mmol) at 0 – 10 °C. The mixture was stirred at the same temperature for 15 min, then charged parallelly with the content of reactor-1 and the solution of dicyclohexyl carbodimide (52.4 g, in 50% toluene, 126.98 mmol) within 1 hr while maintaining the batch temperature at 0 – 10 °C. The mixture was agitated at the same temperature for 3 hrs, and warmed to 25 °C for another 1 hr. Once III was consumed, toluene (-300 mL) was distilled off under reduced pressure at 70 – 80 °C. n-Butanol (200 g) was added, followed by 3 M HCI solution in n-butanol (188 g) while maintaining the Case No.: 09-0592-PCT
temperature at 70 – 80 °C (Gas evolution, product precipitates). After stirring for over 30 min. at 70 – 80 °C, the mixture was cooled to 20 – 30 °C over 1 hr. The precipitate was filtered and washed with acetone (172 g) and toluene (88 g). The wet cake was dried in vacuo at -60 °C to give V toluene solvate as off white solid (60 – 72 g, 85 – 95% yield). Compound V could be used directly for the next step or basified prior to next step to obtain the free base compound VI used in the next step.
Step 9. Synthesis of (E)-Butyl 3-(2-(l-(2-(5-Bromopyrimidin-2-yl)-3-cyclopentyl-l- hydroxy-lH-indole-6-carboxamido)cyclobutyl)-l-methyl-lH-benzo[d]imidazol-6- yl)acrylate VII
Figure imgf000033_0001
5) MeOH/H20
Notes:
The conversion of the acid into acid chloride was achieved using inexpensive thionyl chloride in the presence of catalytic amount of NMP or DMF. An efficient crystallization was developed for the isolation of the desired product in high yield and purity.
Procedure (using free base VI):
To the suspension of 2-(5-bromopyrimidin-2-yl)-3-cyclopentyl-l-methyl-lH-indole-6- carboxylic acid II (see Step 4) (33.36 g, 90.0 wt %, containing -0.2 equiv of NMP from previous step,75.00 mmol) in THF (133.4 g) was added thionyl chloride (10.71 g). The mixture was stirred at 25+5 °C for at least 1 h. After the conversion was completed as determined by HPLC (as derivative of diethylamine), the mixture was cooled to 10+5 °C and N,N-diisopropylethylamine (378.77 g, 300 mmol) below 25 °C. A solution of (E)-butyl 3-(2-(l-aminocyclobutyl)-l-methyl-lH-benzo[if|imidazol-6-yl)acrylate VI (25.86 g, 97.8 Wt%, 77.25 mmol) dissolved in THF (106.7 g) was added at a rate to maintain the Case No.: 09-0592-PCT
temperature of the content < 25 °C. The mixture was stirred at 25+5 °C for at least 30 min for completion of the amide formation. The mixture was distilled at normal pressure to remove ca. 197 mL (171.5 g) of volatiles (Note: the distillation can also be done under reduced pressure). The batch was adjusted to 40+5 °C, and MeOH (118.6 g) was added. Water (15.0 g) was added and the mixture was stirred at 40+5 °C until crystallization occurred (typically in 30 min), and held for another 1 h. Water (90 g) was charged at 40+5 °C over 1 h, and the batch was cooled to 25+5 °C in 0.5 h, and held for at least 1 h. The solid was filtered, rinsed with a mixture of MeOH (39.5 g), water (100 g), and dried in vacuo (< 200 Torr) at 50+5 °C to give (E)-butyl 3-(2-(l-(2-(5-bromopyrimidin-2-yl)-3- cyclopentyl- 1 -methyl- lH-indole-6-carboxamido)cyclobutyl)- 1 -methyl- 1H- benzo[if|imidazol-6-yl)acrylate VII (51.82 g, 96.6 % yield) with a HPLC purity of 98.0 A% (240 nm) and 99.0 Wt%.
Alternative Process (using compound V from Step 8)
To reactor 1 was charged 2-(5-bromopyrimidin-2-yl)-3-cyclopentyl-l-methyl-lH-indole-6- carboxylic acid II (33.6 g), toluene (214 g) and N-methylpyrrolidone (1.37 g). The mixture was heated to 40 °C, then added a solution of thionyl chloride (13 g) in toluene (17 g). The mixture was stirred at 40 °C for at least 0.5 h and cooled to 30 °C. To a second reactor was charged with compound V (the bis-HCl salt toluene solvate from Step 8) (39.4 g), toluene (206 g) and N,N-diisopropylethylamine (70.8 g) at 25 °C. The content of reactor 1 was transferred to reactor 2 at 30 °C and rinsed with toluene (50 g). The mixture was stirred at 30 °C for another 0.5 h, then charged with isopropanol (84 g) and water (108 g) while maintained the temperature at 25 °C. After stirring for 10 min, remove the aqueous phase after phase cutting. To the organic phase was charged isopropanol (43 g), water (54 g) and stirred for 10 min. The aqueous phase was removed after phase cutting. The mixture was distilled under reduced pressure to remove ca.250 mL of volatiles, followed by addition of methyl tert-butyl ether (MTBE, 238 g). The batch was stirred at 65 °C for over 1 hr, then cooled to 20 C over 1 hr and held for another 1 hr at the same temperature. The solid was filtered, rinsed with MTBE (95 g), and dried in vacuo at 80 °C to give (E)-butyl 3-(2-(l-(2- Case No.: 09-0592-PCT
(5-bromopyrimidin-2-yl)-3-cyclopentyl-l-methyl-lH-indole-6-carboxamido)cyclobutyl) methyl- lH-benzo[if|imidazol-6-yl)acrylate VII as a beige solid (50 g, 90 % yield).
Step 10. Synthesis of (E)-3-(2-(l-(2-(5-Bromopyrimidin-2-yl)-3-cyclopentyl-l-methyl- lH-indole-6-carboxamido)cyclobutyl)-l-methyl-lH-benzo[</]imidazol-6-yl)acrylic acid (Compound (1))
Figure imgf000035_0001
Notes:
In this process, hydrolysis of (E)-butyl 3-(2-(l-(2-(5-bromopyrimidin-2-yl)-3-cyclopentyl- l-methyl-lH-indole-6-carboxamido)cyclobutyl)-l-methyl-lH-benzo[d]imidazol-6- yl)acrylate was carried out in mixture of THF/MeOH and aq NaOH. Controlled acidification of the corresponding sodium salt with acetic acid is very critical to obtain easy-filtering crystalline product in high yield and purity.
Procedure:
To the suspension of (E)-butyl 3-(2-(l-(2-(5-bromopyrimidin-2-yl)-3-cyclopentyl-l- methyl-lH-indole-6-carboxamido)cyclobutyl)-l-methyl-lH-benzo[(i]imidazol-6- yl)acrylate VII (489.0 g, 91.9 Wt%, 633.3 mmol) in THF (1298 g) and MeOH (387 g) was added 50% NaOH (82.7 g, 949.9 mmol), followed by rinse with water (978 g). The mixture was stirred between 65-68 C for about 1 h for complete hydrolysis. The resulting solution was cooled to 35 C, and filtered through an in-line filter (0.5 micron), and rinsed with a pre-mixed solution of water (978 g) and MeOH (387 g). The solution was heated to Case No.: 09-0592-PCT
60 +4 C, and acetic acid (41.4 g, 689 mmol) was added over 1 h while the mixture was well agitated. The resulting suspension was stirred at 60 ±4 C for 0.5 h. Another portion of acetic acid (41.4 g, 689 mmol) was charged in 0.5 h, and batch was stirred at 60 ±4 C for additional 0.5 h. The batch was cooled to 26 ±4 C over 1 h and held for 1 h. The batch was filtered, rinsed with a premixed solution of water (1956 g) and MeOH (773.6 g), dried at 50 C under vacuum to give (E)-3-(2-(l-(2-(5-bromopyrimidin-2-yl)-3-cyclopentyl-l- methyl-lH-indole-6-carboxamido)cyclobutyl)-l-methyl-lH-benzo[(i]imidazol-6-yl)acrylic acid (1) (419.0 g, 95 % yield) with > 99.0 A% (240 nm) and 94.1 Wt% by HPLC. Step 11. Formation of Compound (1) Sodium Salt (Type A)
Figure imgf000036_0001
To a reactor were charged Compound (1) (150 g, mmol), THF (492 mL), H20 (51 mL) and 45% aqueous NaOH solution (20.4 g, mmol). The mixture was stirred for >1 hr at -25 °C to form a clear solution (pH = 9 -11). To the solution was charged a suspension of Charcoal (1.5 g) and H20 (27 mL). The mixture was stirred at -35 °C for >30 min and filtered. The filter was rinsed with THF (108 mL) and H20 (21 mL). The filtrate was heated to 50 °C and charged with methyl ethylketone (MEK) (300 mL). The mixture was seeded with Compound (1) sodium salt MEK solvate (Type A) seeds (0.5 g) and stirred for another 1 hr at 50 °C. To the mixture was charged additional MEK (600 mL). The resultant mixture was stirred for another 1 hr at 50 °C and then cooled to 25 °C. The precipitate was filtered and rinsed with MEK twice (2 x 300 mL). The wet cake was dried in vacuum at 80 °C to give Compound (1) sodium salt (Type A) (145.6 g, 94%). Case No.: 09-0592-PCT
The Compound (1) sodium salt (Type A) MEK solvate seeds used in the above process step can be manufactured by the above process except without using seeds and without drying of the solvate.

ANTHONY MELVIN CRASTO

click

http://drugsynthesisint.blogspot.in/p/vir-series-hep-c-virus-22.html

AND

http://medcheminternational.blogspot.in/p/vir-series-hep-c-virus.html

GRAZOPREVIR, MK 5172


GRAZOPREVIR

  • Grazoprevir hydrate
  • UNII-4O2AB118LA
  • MK 5172
THERAPEUTIC CLAIM Antiviral
Note……..drug is k salt
MF C38H49N6O9SK
MW804.99
CHEMICAL NAMES
1. Cyclopropanecarboxamide, N-[[[(1R,2R)-2-[5-(3-hydroxy-6-methoxy-2-
quinoxalinyl)pentyl]cyclopropyl]oxy]carbonyl]-3-methyl-L-valyl-(4R)-4-hydroxy-L-prolyl-1-
amino-N-(cyclopropylsulfonyl)-2-ethenyl-, cyclic (1→2)-ether, hydrate (1 :1) (1R,2S)-
2. (1aR,5S,8S,10R,22aR)-N-{(1R,2S)-1-[(cyclopropylsulfonyl)carbamoyl]-2-
ethenylcyclopropyl}-5-(1,1-dimethylethyl)-14-methoxy-3,6-dioxo-
1,1a,3,4,5,6,9,10,18,19,20,21,22,22a-tetradecahydro-8H-7,10-
methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxaline-8-
carboxamide hydrate
MOLECULAR FORMULA C38H50N6O9S.H2O
MOLECULAR WEIGHT 784.92
SPONSOR Merck Sharp & Dohme Corp.
CAS REGISTRY NUMBER 1350462-55-3  HYDRATE, 1350514-68-9 (anhydrous)
WHO NUMBER
9857
GRAZOPREVIR
MERCK
MK-5172 is in phase II clinical development at Merck & Co. for the oral treatment of chronic hepatitis C in combination with peginterferon and ribavirin and in combination with MK-8742. Phase I clinical trials are ongoing for the treatment of hepatitis C in patients with genotype 1 and genotype 3. In 2013, breakthrough therapy designation was assigned to the compound.
 SYNTHESIS, THESIS PROCEDURES, NMR see………..http://www.allfordrugs.com/2015/07/31/mk-5172-grazoprevir/
Discovery of MK-5172, a macrocyclic hepatitis C virus NS3/4a protease inhibitor
ACS Med Chem Lett 2012, 3(4): 332DOI: 10.1021/ml300017p
Development of a practical, asymmetric synthesis of the hepatitis c virus protease inhibitor MK-5172
Org Lett 2013, 15(16): 4174
WO2013142159
WO 2013106631
WO 2013101550
WO 2013028470
WO 2013028471
WO2013028465
WO 2010011566
Description:
IC50 Value: 7.4nM and 7nM for genotype1b and 1a respectively, in replicon system [1]
MK-5172 is a novel P2-P4 quinoxaline macrocyclic HCV NS3/4a protease inhibitor currently in clinical development.
in vitro: In biochemical assays, MK-5172 was effective against a panel of major genotypes and variants engineered with common resistant mutations observed in clinical studies with other NS3/4a protease inhibitors. In the replicon assay, MK-5172 demonstrated subnanomolar to low-nanomolar EC50s against genotypes 1a, 1b, and 2a [2].
in vivo: In rats, MK-5172 showed a plasma clearance of 28 ml/min/kg and plasma half-life of 1.4 hr. When dosed p.o. at 5 mg/kg, the plasma exposure of MK-5172 was good with an AUC of 0.7 uM.hr. The liver exposure of the compound was quite good (23 uM at 4 hr), and MK-5172 remained in liver 24 hr after a single p.o. 5 mg/kg dose. At 24 hr, the liver concentration of MK-5172 was 0.2 uM, which was over 25-fold higher than the IC50 in the replicon assay with 50% NHS. When dosed to dogs, MK-5172 showed low clearance of 5 ml/min/kg and a 3 hr half-life after i.v. 2 mg/kg dosing and had good plasma exposure (AUC=0.4 uM.hr) after a p.o. 1 mg/kg dose [1].
Clinical trial: Evaluation of Hepatic Pharmacokinetics for MK-5172 in Participants With Chronic Hepatitis C . Phase1
Hepatitis C virus (HCV) infection is a major health problem that leads to chronic liver disease, such as cirrhosis and hepatocellular carcinoma, in a substantial number of infected individuals. Current treatments for HCV infection include immunotherapy with recombinant interferon-α alone or in combination with the nucleoside analog ribavirin.
Several virally-encoded enzymes are putative targets for therapeutic intervention, including a metalloprotease (NS2-3), a serine protease (NS3), a helicase (NS3), and an RNA-dependent RNA polymerase (NS5B). The NS3 protease is located in the N-terminal domain of the NS3 protein. NS4A provide a cofactor for NS3 activity.
Potential treatments for HCV infection have been discussed in the different references including Balsano, Mini Rev. Med. Chem. 8(4):307-318, 2008, Rönn et al., Current Topics in Medicinal Chemistry 8:533-562, 2008, Sheldon et al., Expert Opin. Investig. Drugs 16(8):1171-1181, 2007, and De Francesco et al., Antiviral Research 58:1-16, 2003
Different HCV inhibitors are described in different publications. Macrocyclic compounds useful as inhibitors the HCV protease inhibitors are described in WO 06/119061, WO 7/015785, WO 7/016441, WO 07/148,135, WO 08/051,475, WO 08/051,477, WO 08/051,514, WO 08/057,209. Additional HCV NS3 protease inhibitors are disclosed in International Patent Application Publications WO 98/22496, WO 98/46630, WO 99/07733, WO 99/07734, WO 99/38888, WO 99/50230, WO 99/64442, WO 00/09543, WO 00/59929, WO 02/48116, WO 02/48172, British Patent No. GB 2 337 262, and U.S. Pat. No. 6,323,180.
………………………
NMR
Figure US08080654-20111220-C00021
13C NMR (100 MHz, DMSO-d6) δ 172.32, 170.63, 169.04, 159.86, 156.95, 154.74, 148.10, 140.41, 133.55 (2 signals), 128.94, 118.21, 117.58, 105.89, 74.88, 59.75, 58.71, 55.68, 54.13, 54.01, 40.13, 34.49, 34.04, 33.76, 32.68, 30.71, 30.43, 28.55, 27.69, 27.28, 26.38, 21.98, 18.49, 10.67, 5.69, 5.46; MS (ES+) m/z 767 (M+H)+
(1aR,5S,8S,10R,22aR)-5-tert-butyl-N-((1R,2S)-1-{[(cyclopropylsulfonyl)amino]carbonyl}-2-vinylcyclopropyl)-14-methoxy-3,6-dioxo-1,1a,3,4,5,6,9,10,18,19,20,21,22,22a-tetradecahydro-8H-7,10-methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxaline-8-carboxamide
index1
………………….
NMR OF GRAZOPREVIR K SALT
Potassium {[(1R,2S)-1-({[(1aR,5S,8S,10R,22aR)-5-tert-butyl-14-methoxy-3,6-dioxo-
1,1a,3,4,5,6,9,10,18,19,20,21,22,22a-tetradecahydro-8H-7,10-
methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxalin-8-
yl]carbonyl}amino)-2-ethenylcyclopropyl]carbonyl}(cyclopropylsulfonyl)azanide (15 K-salt).
1H NMR (400 MHz, DMSO-d6) δ 7.91 (br s, 1 H), 7.75 (d, J =
8.3 Hz, 1 H), 7.15 (m, 1 H), 7.04 (m, 1 H), 5.97 (m, 1 H), 5.73 (br s, 1 H), 4.96 (m, 1 H), 4.79 (apparent q, J = 9.3 Hz, 1 H), 4.26 (dd, J = 9.7, 7.7 Hz, 1 H), 4.20 (d, J = 11.3 Hz, 1 H), 4.14 (d, J = 8.8 Hz, 1 H), 3.90 (dd, J = 11.1, 3.2 Hz, 1 H), 3.86 (s, 3 H), 3.62 (m, 1 H), 2.86-2.60 (m, 3 H), 2.38 (m, 1 H), 2.21 (m, 1 H), 1.80-1.48 (m, 6 H), 1.42 (m, 5 H), 1.14 (m, 1 H), 0.95 (m, 10 H), 0.81 (m, 2 H), 0.72-0.50 (m, 3 H), 0.41 (m, 1 H) ppm.http://pubs.acs.org/doi/suppl/10.1021/ml300017p/suppl_file/ml300017p_si_001.pdf
………………………………………………………
GRAZOPREVIR
(1aR,5S,8S,10R,22aR)-5-tert-Butyl-N-((1R,2S)-1-{[(cyclopropylsulfonyl)amino] carbonyl}-2-
vinylcyclopropyl)-14-methoxy-3,6-dioxo-1,1a,3,4,5,6,9,10,18,19,20,21,22,22a-tetradecahydro-8H-
7,10-methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxaline-8-
carboxamide (MK-5172, 15).
1H NMR (400 MHz, CD3
OD) δ 7.79 (dd, J = 9.6, 1.8 Hz, 1 H), 7.23 (s, 1 H), 7.22 (m, 1 H), 7.10 (d, J = 9.6 Hz, 1 H), 6.01 (apparent t, J = 3.6 Hz, 1 H), 5.74 (m, 1 H), 5.24 (dd, J = 17.0 Hz, 1.6 Hz, 1 H), 5.11 (dd, J = 10.4 Hz, 1.6 Hz, 1 H), 4.49 (d, J = 11.2 Hz, 1 H), 4.40 (m, 2 H), 4.13 (dd, J = 12.0 Hz, 4.0 Hz, 1 H), 3.92 (s, 3 H), 3.76 (m, 1 H), 2.92 (m, 2 H), 2.85 (m, 1 H), 2.55 (dd, J = 13.6 Hz, 6.4 Hz, 1 H), 2.28 (m, 1 H), 2.18 (apparent q, J =8.8 Hz, 1 H), 1.85 (dd, J = 8.0 Hz, 5.6 Hz, 1 H), 1.73 (m, 2 H), 1.5 (m, 2 H), 1.40 (dd, J = 9.6 Hz, 5.6 Hz, 1 H), 1.3 (m, 2 H), 1.23 (m, 4 H), 1.08 (s, 9 H), 0.99 (m, 2 H), 0.89 (m, 3 H), 0.73 (m, 1 H), 0.49 (m, 1 H) ppm; HRMS (ESI) m/z 767.3411 [(M+H)+; calcd for C38H51N6O9S: 767.3433].http://pubs.acs.org/doi/suppl/10.1021/ml300017p/suppl_file/ml300017p_si_001.pdf
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HPLC
……………………
SYNTHESIS OF INTERMEDIATES Intermediates A
Intermediate # Structure Name Lit. Reference
A1 Figure US08080654-20111220-C00003 (1R,2S)-1-Amino-N- (cyclopropylsulfonyl)-2- vinylcyclopropanecarboxamide hydrochloride Wang et al., U.S. Pat. No. 6,995,174
Intermediate B1 3-methyl-N-({[(1R,2R)-2-pent-4-en-1-ylcyclopropyl]oxy}carbonyl)-L-valine
Figure US08080654-20111220-C00004
Step 1: [(1E)-hepta-1,6-dien-1-yloxy](trimethyl)silane
Figure US08080654-20111220-C00005
A solution (0.5 M) of butenyl magnesium bromide in THF (1.4 eq) was treated at −78° C. with Cu(I) Br.SMe(0.05 eq) and HMPA (2.4 eq). The mixture was stirred for 10 min, then a solution (1 M) of acrolein (1 eq) and TMSCl (2 eq) in THF was added over 1 h such that the internal temperature remained below −68° C. The resulting mixture was stirred at −78° C. for 2 h, then treated with excess Et3N and diluted with hexane. After reaching room temperature, the mixture was treated with a small portion of H2O and filtered through CELITE. The filtrate was washed 10 times with H2O and then with brine. The organic layer was dried, and the volatiles were removed to give a residue that was distilled under reduced pressure (20 mbar). The fraction collected at 80-86° C. contained the title compound (58%) as a colorless liquid. 1H NMR (400 MHz, CDCl3) δ 6.19 (d, J=11.6 Hz, 1H), 5.85-5.75 (m, 1H), 5.02-4.92 (m, 3H), 2.08-2.02 (m, 2H), 1.94-1.88 (m, 2H), 1.46-1.38 (m, 2H), 0.18 (s, 9H).
Step 2: trans-2-pent-4-en-1-ylcyclopropanol
Figure US08080654-20111220-C00006
A solution (0.45 M) of the preceding compound in hexane was treated with a solution (15%) of Et2Zn (1.2 eq) in toluene, and the resulting solution was cooled in an ice bath. Diiodomethane (1.2 eq) was added dropwise, then the solution was stirred for 1 h before being warmed to 20° C. Pyridine (6 eq) was added, and the slurry was stirred for 15 min then poured onto petroleum ether. The mixture was filtered repeatedly through CELITE until a transparent solution was obtained. This mixture was concentrated at 100 mbar, and the solution that remained (that contained trimethyl{[(trans)-2-pent-4-en-1-ylcyclopropyl]oxy}silane, toluene and pyridine) was further diluted with THF. The mixture was cooled to 0° C. then treated dropwise with a solution (1 M) of TBAF (1.2 eq) in THF. After 10 min, the mixture was allowed to warm to 20° C., and after a further 1 h was poured into H2O. The aqueous phase was extracted with EtOAc, and the combined organic extracts were washed with brine then dried. Removal of the volatiles afforded a residue that was purified by flash chromatography (eluent 0-66% Et2O/petroleum ether) to furnish the title compound (71%) as a colorless liquid. 1H NMR (400 MHz, CDCl3) δ 5.85-5.75 (m, 1H), 5.00 (dd, J=17.1, 1.6 Hz, 1H), 4.94 (br d, J=10.4 Hz, 1H), 3.20 (apparent dt, J=6.4, 2.5 Hz, 1H), 2.10-2.04 (m, 2H), 1.52-1.44 (m, 2H), 1.29-1.19 (m, 1H), 1.15-1.07 (m, 1H), 0.95-0.87 (m, 1H), 0.71-0.66 (m, 1H), 0.31 (apparent q, J=6.0 Hz, 1H).
Step 3: methyl 3-methyl-N-(oxomethylene)-L-valinate
Figure US08080654-20111220-C00007
A solution (0.39 M) of methyl 3-methyl-L-valinate in a 2:1 mixture of saturated aqueous NaHCOand CH2Clwas cooled in an ice bath and stirred rapidly. The mixture was treated with triphosgene (0.45 eq) in one portion, and the resulting mixture was stirred for 0.5 h. The reaction was diluted with CH2Cl2, and the layers were separated. The aqueous phase was extracted with CH2Cl2, then the combined organics were washed with brine and dried. Removal of the solvent gave the title compound as clear oil that was kept for 12 h under vacuum (0.1 mbar) then used directly in the subsequent step. 1H NMR (400 MHz, CDCl3) δ 3.79 (s, 3H), 3.75 (s, 1H), 1.00 (s, 9H).
Step 4: methyl 3-methyl-N-({[(1R,2R)-2-pent-4-en-1-ylcyclopropyl]oxy}carbonyl)-L-valinate and methyl 3-methyl-N-({[(1S,2S)-2-pent-4-en-1-ylcyclopropyl]oxy}carbonyl)-L-valinate
Figure US08080654-20111220-C00008
A solution (0.45 M) of trans-2-pent-4-en-1-ylcyclopropanol in toluene was treated with methyl 3-methyl-N-(oxomethylene)-L-valinate (1.1 eq) and then DMAP (1 eq). The resulting mixture was heated under reflux for 12 h then cooled to 20° C. H2O and EtOAc were added, and the organic layer was separated and washed with 1N HCl, brine and dried. Removal of the volatiles afforded a residue that was purified twice by flash chromatography (eluent 0-30% Et2O/petroleum ether). The first fractions contained methyl 3-methyl-N-({[(1R,2R)-2-pent-4-en-1-ylcyclopropyl]oxy}carbonyl)-L-valinate (38%) as an oil. MS (ES+) m/z 298 (M+H)+
The later fractions contained methyl 3-methyl-N-({[(1S,2S)-2-pent-4-en-1-ylcyclopropyl]oxy}carbonyl)-L-valinate (28%) as an oil. MS (ES+) m/z 298 (M+H)+
Step 5: 3-methyl-N-({[(1R,2R)-2-pent-4-en-1-ylcyclopropyl]oxy}carbonyl)-L-valine
Figure US08080654-20111220-C00009
A solution (0.1 M) of methyl 3-methyl-N-({[(1R,2R)-2-pent-4-en-1-ylcyclopropyl]oxy}carbonyl)-L-valinate in 2:1 mixture of MeOH/H2O was treated with LiOH.H2O (4 eq) and then heated at 60° C. for 4 h. The mixture was cooled and concentrated to half volume, then diluted with EtOAc and acidified with aqueous HCl (1 N). The organic layer was separated and washed with brine then dried. Removal of the volatiles afforded the title compound (98%) as an oil. MS (ES+) m/z 284 (M+H)+
Intermediates C Intermediate C1 methyl (4R)-4-[(3-chloro-7-methoxyquinoxalin-2-yl)oxy]-L-prolinate hydrochloride
Figure US08080654-20111220-C00010
Step 1: 6-methoxyquinoxaline-2,3-diol
Figure US08080654-20111220-C00011
A suspension of 4-methoxybenzene-1,2-diamine dihydrochloride in diethyl oxalate (8 eq) was treated with Et3N (2 eq) and then heated at 150° C. for 2 h. The mixture was cooled and filtered, and then the collected solid was washed with H2O and EtOH. The residue was dried to give the title compound (69%). MS (ES+) m/z 193 (M+H)+
Step 2: 3-chloro-6-methoxyquinoxalin-2-ol
Figure US08080654-20111220-C00012
A solution (1.53 M) of 6-methoxyquinoxaline-2,3-diol in DMF was treated with SOCl(1 eq) and heated at 110° C. After 1.5 h, the reaction mixture was cooled and poured into aqueous HCl (1 N). The resulting precipitate was filtered and washed with H2O and Et2O. The dried solid contained predominantly the title compound as a mixture with 6-methoxyquinoxaline-2,3-diol and 2,3-dichloro-6-methoxyquinoxaline. This material was used directly in the subsequent step. MS (ES+) m/z 211 (M+H)+
Step 3: 1-tert-butyl 2-methyl (2S,4R)-4-[(3-chloro-7-methoxyquinoxalin-2-yl)oxy]pyrrolidine-1,2-dicarboxylate
Figure US08080654-20111220-C00013
A solution (0.35 M) of 3-chloro-6-methoxyquinoxalin-2-ol in NMP was treated with Cs2CO(1.5 eq) and 1-tert-butyl 2-methyl (2S,4S)-4-{[(4-bromophenyl)sulfonyl]oxy}pyrrolidine-1,2-dicarboxylate (1.1 eq). The resulting mixture was stirred at 50° C. for 18 h, then a further portion (0.1 eq) of 1-tert-butyl 2-methyl (25,45)-4-{[(4-bromophenyl)sulfonyl]oxy}pyrrolidine-1,2-dicarboxylate was added. After stirring for 2 h, the mixture was cooled and diluted with H2O and EtOAc. The organic phases were washed with aqueous HCl (1 N), saturated aqueous NaHCOand brine. The dried organic phase was concentrated to a residue that was purified by flash-chromatography (0-60% EtOAc/petroleum ether) to give the title compound (35% for two steps) as a solid. MS (ES+) m/z 438 (M+H)+
Step 4: methyl (4R)-4-[(3-chloro-7-methoxyquinoxalin-2-yl)oxy]-L-prolinate hydrochloride
Figure US08080654-20111220-C00014
A solution (0.62 M) of 1-tert-butyl 2-methyl (2S,4R)-4-[(3-chloro-7-methoxyquinoxalin-2-yl)oxy]pyrrolidine-1,2-dicarboxylate in CH2Clwas treated with a solution (4 M) of HCl in dioxane (5 eq). The mixture was stirred at 20° C. for 2 h, then treated with a solution (4 M) of HCl in dioxane (2 eq). After 5 h, the reaction was judged complete and the mixture was concentrated under reduced pressure. The residue was triturated with Et2O to give the title compound (95%) as a solid. MS (ES+) m/z 338 (M+H)+
Example 1 Potassium {[(1R,2S)-1-({[(1aR,5S,8S,10R,22aR)-5-tert-butyl-14-methoxy-3,6-dioxo-1,1a,3,4,5,6,9,10,18,19,20,21,22,22a-tetradecahydro-8H-7,10-methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxalin-8-yl]carbonyl}amino)-2-vinylcyclopropyl]carbonyl}(cyclopropylsulfonyl)azanide
Figure US08080654-20111220-C00015
Step 1: methyl 3-methyl-N-({[(1R,2R)-2-pent-4-en-1-ylcyclopropyl]oxy}carbonyl)-L-valyl-(4R)-4-[(3-chloro-7-methoxyquinoxalin-2-yl)oxy]-L-prolinate
Figure US08080654-20111220-C00016
A solution (0.2 M) of methyl (4R)-4-[(3-chloro-7-methoxyquinoxalin-2-yl)oxy]-L-prolinate hydrochloride in DMF was treated with 3-methyl-N-({[(1R,2R)-2-pent-4-en-1-ylcyclopropyl]oxy}carbonyl)-L-valine (1.1 eq), DIEA (5 eq) and HATU (1.2 eq). The resulting mixture was stirred at 20° C. for 5 h, then diluted with EtOAc. The organic layer was separated and washed with aqueous HCl (1 N), saturated aqueous NaHCOand brine. The dried organic phase was concentrated under reduced pressure to give a residue that was purified by flash chromatography (eluent 10-30% EtOAc/petroleum ether) to furnish the title compound (96%) as an oil. MS (ES+) m/z 604 (M+H)+
Step 2: methyl 3-methyl-N-({[(1R,2R)-2-pent-4-en-1-ylcyclopropyl]oxy}carbonyl)-L-valyl-(4R)-4-[(7-methoxy-3-vinylquinoxalin-2-yl)oxy]-L-prolinate
Figure US08080654-20111220-C00017
A solution (0.1 M) of methyl 3-methyl-N-({[(1R,2R)-2-pent-4-en-1-ylcyclopropyl]oxy}carbonyl)-L-valyl-(4R)-4-[3-chloro-7-methoxyquinoxalin-2-yl)oxy]-L-prolinate in EtOH was treated with potassium trifluoro(vinyl)borate (1.5 eq) and triethylamine (1.5 eq). The resulting mixture was degassed, then PdCl2(dppf)-CH2Cladduct (0.1 eq) was added. The mixture was heated under reflux for 1 h, then cooled to room temperature and diluted with H2O and EtOAc. The organic phase was separated, washed with H2O and brine then dried. Removal of the volatiles afforded a residue that was purified by flash chromatography (20-30% EtOAc/petroleum ether) to give the title compound as a yellow foam that was used directly in the subsequent step. MS (ES+) m/z 595 (M+H)+
Step 3: methyl (1aR,5S,8S,10R,18E,22aR)-5-tert-butyl-14-methoxy-3,6-dioxo-1,1a,3,4,5,6,9,10,20,21,22,22a-dodecahydro-8H-7,10-methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxaline-8-carboxylate
Figure US08080654-20111220-C00018
A solution (0.02 M) of methyl 3-methyl-N-({[(1R,2R)-2-pent-4-en-1-ylcyclopropyl]oxy}carbonyl)-L-valyl-(4R)-4-[(7-methoxy-3-vinylquinoxalin-2-yl)oxy]-L-prolinate in DCE was heated to 80° C. then treated with Zhan 1 catalyst (0.15 eq). The resulting mixture was stirred at 80° C. for 1 h, then cooled to room temperature and concentrated under reduced pressure. The residue was purified by flash chromatography (20-50% EtOAc/petroleum ether) to give the title compound (25% for 2 steps) as a foam. MS (ES+) m/z 567 (M+H)+
Step 4: methyl (1aR,5S,8S,10R,22aR)-5-tert-butyl-14-methoxy-3,6-dioxo-1,1a,3,4,5,6,9,10,18,19,20,21,22,22a-tetradecahydro-8H-7,10-methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxaline-8-carboxylate
Figure US08080654-20111220-C00019
A solution (0.05 M) of methyl (1aR,5S,8S,10R,18E,22aR)-5-tert-butyl-14-methoxy-3,6-dioxo-1,1a,3,4,5,6,9,10,20,21,22,22a-dodecahydro-8H-7,10-methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxaline-8-carboxylate in MeOH/dioxane (1:1 ratio) was treated with Pd/C (8% in weight). The resulting mixture was stirred under atmosphere of hydrogen for 4 h. The catalyst was filtered off, and the filtrate was concentrated under reduced pressure to give the title compound (98%) as a solid. MS (ES+) m/z 569 (M+H)+
Step 5: (1aR,5S,8S,10R,22aR)-5-tert-butyl-14-methoxy-3,6-dioxo-1,1a,3,4,5,6,9,10,18,19,20,21,22,22a-tetradecahydro-8H-7,10-methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxaline-8-carboxylic acid
Figure US08080654-20111220-C00020
A solution (0.1 M) of methyl (1aR,5S,8S,10R,22aR)-5-tert-butyl-14-methoxy-3,6-dioxo-1,1a,3,4,5,6,9,10,18,19,20,21,22,22a-tetradecahydro-8H-7,10-methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxaline-8-carboxylate in a 1:1 mixture of H2O/THF was treated with LiOH.H2O (3 eq). The resulting mixture was stirred at 20° C. for 18 h, acidified with aqueous HCl (0.2 M) and diluted with EtOAc. The organic phase was separated, washed with aqueous HCl (0.2 M) and brine then dried. Removal of the volatiles afforded the title compound (98%) as a solid. MS (ES+) m/z 555 (M+H)+
Step 6: (1aR,5S,8S,10R,22aR)-5-tert-butyl-N-((1R,2S)-1-{[(cyclopropylsulfonyl)amino]carbonyl}-2-vinylcyclopropyl)-14-methoxy-3,6-dioxo-1,1a,3,4,5,6,9,10,18,19,20,21,22,22a-tetradecahydro-8H-7,10-methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxaline-8-carboxamide
Figure US08080654-20111220-C00021
A solution (0.1 M) of (1aR,5S,8S,10R,22aR)-5-tert-butyl-14-methoxy-3,6-dioxo-1,1a,3,4,5,6,9,10,18,19,20,21,22,22a-tetradecahydro-8H-7,10-methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxaline-8-carboxylic acid in CH2Clwas treated with (1R,2S)-1-{[(cyclopropylsulfonyl)amino]carbonyl}-2-vinylcyclopropanaminium chloride (1.3 eq), DIEA (3 eq), DMAP (1.5 eq) and TBTU (1.45 eq). The resulting mixture was stirred at 20° C. for 18 h and then diluted with EtOAc. The solution was washed with aqueous HCl (0.2 M), saturated aqueous NaHCOand brine. The organic phases were dried and concentrated to give a residue that was purified by flash-chromatography (eluent 2.5% MeOH/CH2Cl2) to give the title compound (89%) as a solid. 13C NMR (100 MHz, DMSO-d6) δ 172.32, 170.63, 169.04, 159.86, 156.95, 154.74, 148.10, 140.41, 133.55 (2 signals), 128.94, 118.21, 117.58, 105.89, 74.88, 59.75, 58.71, 55.68, 54.13, 54.01, 40.13, 34.49, 34.04, 33.76, 32.68, 30.71, 30.43, 28.55, 27.69, 27.28, 26.38, 21.98, 18.49, 10.67, 5.69, 5.46; MS (ES+) m/z 767 (M+H)+
GRAZOPREVIR POTASSIUM
Step 7: potassium {[(1R,2S)-1-({[(1aR,5S,8S,10R,22aR)-5-tert-butyl-14-methoxy-3,6-dioxo-1,1a,3,4,5,6,9,10,18,19,20,21,22,22a-tetradecahydro-8H-7,10-methanocyclopropa[18,19][1,10,3,6]dioxadiazacyclononadecino[11,12-b]quinoxalin-8-yl]carbonyl}amino)-2-vinylcyclopropyl]carbonyl}(cyclopropylsulfonyl)azanide
Figure US08080654-20111220-C00022
The preceding material was taken up in EtOH and the resulting solution (0.025 M) was cooled to 0° C. A solution (0.02 M) of tert-BuOK (1.5 eq) in EtOH was added leading to the formation of a precipitate. The mixture was stirred at 20° C. for 18 h, then the solid was collected by filtration. This material was washed with EtOH and dried to give the title compound (93%) as a white crystalline solid. MS (ES+) m/z 767 (M+H)+http://www.google.nl/patents/US8080654
………………………..
PATENT
WO 2015095437

Step 1: Quinoxaline Hydroxyproline Methyl Ester HCl Salt

A 250-ml RB, equipped with magnetic stirrer and N2 bubbler, was charged with chloroquinoxaline BOC hydroxyproline adduct in MeOH (100 ml), and the mixture was cooled in an ice bath. Acetyl chloride (17.9 g) was then added, and the mixture was stirred at RT for 2 h. The batch was diluted with IP Ac (80 ml). Solids were filtered off and washed with IPAc (20 ml). The washed solids were dried under vacuum for 3 d, to provide 48.9 g (100% yield ). Part of this material was used in the next step.

…………………..
WO2015057611

Example 17: Preparation of Compound A, Method A

Macrocyclic acid hemihydrate, the product of Example 15 (10.16 g, 18.03 mmol) was dissolved in THF (50 mL to 90 mL). The solution was azetropically dried at a final volume of 100 mL. Sulfonamide pTSA salt (7.98 g, 1.983 mmol) followed by DMAc (15 mL) was added at RT. The batch was cooled to 0°C to 10°C, and pyridine (10 mL) was added dropwise. Then, EDC HCl (4.49 g, 23.44 mmol) was added in portions or one portion at 0°C to 10°C. The reaction mixture was aged at 0°C to 10°C for 1 h, and then warmed to 15°C to 20°C for 2 h to 4 h. MeOAc (100 mL) followed by 15 wt% citric acid in 5% NaCl in water (50 mL) was added, while the internal temperature was maintained to < 25°C with external cooling. The separated organic phase was washed with 15 wt% citric acid in 5% NaCl in water (50 mL) followed by 5% NaCl (50 mL). The organic phase was solvent-switched to acetone at a final volume of ~80 mL. Water (10 mL) was added dropwise at 35°C to 40°C. The batch was seeded with Compound A monohydrate form III (~10 mg) and aged for 0.5 h tol h at 35°C to 40°C. Additional water (22 mL) was added dropwise over 2 h to 4 h at 35°C to 40°C. The slurry was aged at 20°C for 2 h to 4 h before filtration. The wet cake was displacement washed with 60% acetone in water (2x 40 mL). Suction drying at RT gave Compound A monohydrate form III as a white solid.

XH NMR (400 MHz, CDC13) δ 9.95 (s, br, 1 H), 7.81 (d, J = 9.1 Hz, 1 H), 7.18 (dd, J = 9.1, 2.7 Hz, 1 H), 7.16 (s, br, 1 H), 7.13 (d, J = 2.7 Hz, 1 H), 5.96 (t, J = 3.8 Hz, 1 H), 5.72 (m, 1 H), 5.68 (d, J = 10.1 Hz, 1 H), 5.19 (d, J = 17.1 Hz, 1 H), 5.07 (d, J = 10.1 Hz, 1 H), 4.52 (d, J = 11.4 Hz, 1 H), 4.45 (d, J = 9.8 Hz, 1 H), 4.36 (d, J = 10.5, 6.9 Hz, 1 H), 4.05 (dd, J = 11.5, 3.9 Hz, 1 H), 3.93 (s, 3 H), 3.78 (m, 1 H), 2.90 (m, 1 H), 2.82 (tt, J = 8.0, 4.8 Hz, 1 H), 2.74 (dt, J = 13.2, 4.8 Hz, 1 H), 2.59 (dd, J = 14.0, 6.7 Hz, 1 H), 2.40 (ddd, J = 14.0, 10.6, 4.0 Hz, 1 H), 2.10 (dd, J = 17.7, 8.7 Hz, 1 H), 1.98 (2 H, mono hydrate H20), 1.88 (dd, J 8.2, 5.9 Hz, 1 HO, 1.74 (m, 3 H), 1.61 (m, 1 H), 1.50 (m, 3 H), 1.42 (dd, J = 9.6, 5.8 Hz, 1 H), 1.22 (m, 2 H), 1.07 (s, 9 H), 0.95 (m, 4 H), 0.69 (m, 1 H), 0.47 (m, 1 H).

1 C NMR (100 MHz, CDC13) δ 173.5, 172.1, 169.1, 160.4, 157.7, 154.9, 148.4, 141.0, 134.3, 132.7, 129.1, 118.8, 118.7, 106.5, 74.4, 59.6, 59.4, 55.8, 55.5, 54.9, 41.8, 35.4, 35.3, 35.2, 34.3,. 31.2, 30.7, 29.5, 28.6, 28.2, 26.6, 22.6, 18.7, 11.2, 6.31, 6.17.

HPLC conditions: Ascentis Express Column, 10 cm x 4.6 mm, 2.7 μηι; Column temperature of 40°C; Flow rate of 1.8 mL/min; and Wavelength of 215 nm.

Gradiant: mm 0.1% ¾PO4

0 20 80

5 55 45

15 55 45

25 95 5

27 95 5

27.1 20 80

32 20 80

Retention time: mm.

Compound A 14.50

Example 18: Preparation of Compound A, Method B

To a 50-L flask equipped with overhead stirring was added macrocyclic acid (1.06 kg crude, 1.00 eq), amine-pTSA (862 g crude, 1.12 eq) and MeCN (7.42 L) at 19°C. The slurry was cooled in a water bath, pyridine (2.12 L, 13.8 eq) was added, aged 15 min, and then added EDC (586 g, 1.60 eq) in one portion, aged 1.5 h, while it turned into a clear homogeneous solution.

The solution cooled in a water bath, then quenched with 2 N HC1 (1.7 L), and seeded (9.2 g), aged 15 min, and the rest of the aqueous HC1 was added over 2.5 h. A yellow slurry was formed. The slurry was aged overnight at RT, filtered, washed with MeCN/water (1 : 1 v/v, 8 L), to obtain Compound A (Hydrate II).

Compound A was dissolved in acetone (4 L) at RT, filtered and transferred to a

12-L round-bottom flask with overhead stirring, rinsed with extra acetone (1 L), heated to 50°C, water (0.9 L) was added, seeded with Compound A monohydrate form III (-10 mg), and aged 15 min, and then added water (0.8 L) over 2.5 h, extra water 3.3 v over 2.5 h was added, stopped heating, cooled to RT, aged at RT overnight, filtered, washed with water/acetone (1 : 1 v/v, 4 L), and dried in air under vacuum. Compound A Hydrate III, 670 g, was obtained as an off-white solid.

Example 19: Preparation of Compound A, Method C

Macrocyclic acid hemihydrate from Example 15 (10.16 g, 18.03 mmol) was dissolved in THF (50 ml to 90 mL). The solution was azetropically dried at a final volume of 100 mL. Sulfonamide pTSA salt (7.98 g, 19.83 mmol) was added, followed by DMAc (15 mL), at RT. The batch was cooled to 0° to 10°C, and pyridine (10 mL) was added dropwise. Then, EDC HC1 (4.49 g, 23.44 mmol) was added (in portions or one portion) at 0°C to 10°C. The reaction mixture was aged at 0°C to 10°C for 1 h, and then warmed to 15°C to 20°C for 2 h to 4 h. THF (50 mL) was added, followed by 15 wt% citric acid in 15 wt% aq. NaCl (50 mL), while the internal temperature was maintained at < 25°C with external cooling. The separated organic phase was washed with 15 wt% citric acid in 1 % aq. NaCl (40 mL), followed by 15% NaCl (40 mL). The organic phase was solvent-switched to acetone at a final volume of ~75 mL Water (1 1 mL to 12 mL) was added dropwise at 35°C to 40°C. The batch was seeded with Compound A monohydrate form III (~20 mg) and aged for 0.5 h to 1 h at 35°C to 40°C.

Additional water (22 mL) was added dropwise over 2 h to 4 h at 35°C to 40°C. The slurry was aged at 20°C for 2 h to 4 h before filtration. The wet cake was displacement washed with 60% acetone in water (40 mL x 2). Suction drying at RT or vacuum-oven drying at 45°C gave Compound A monohydrate form III as a white solid.

Example 20: Preparation of Compound A, Method D

Macrocyclic acid hemihydrate from Example 12 (10 g, 98.4wt%, 17.74 mmol) was dissolved in THF (70 mL). The solution was azetropically dried at a final volume of ~60 mL. Sulfonamide pTSA salt (7.53 g, 18.7 mmol) was added at RT. The batch was cooled to 0°C to 5°C, and pyridine (1 1.4 mL) was added dropwise. Then, EDC HC1 (4.26 g, 22.2 mmol) was added in portions at 0°C to 15°C. The reaction mixture was aged at 10°C to 15°C for 2 h to 4 h. 35 wt% Citric acid in 10 wt% aq. NaCl (80 mL) was added, while the internal temperature was maintained at < 25°C with external cooling. The separated organic phase was solvent-switched to acetone at a final volume of ~75 mL. Water (12 mL) was added dropwise at 50°C. The batch was seeded with Compound A monohydrate form III (-300 mg) and aged for 0.5 h to 1 h at 50°C. Additional water (25 mL) was added dropwise over 6 h at 35°C to 40°C. The slurry was aged at 20°C for 2 h to 4 h before filtration. The wet cake was displacement washed with 65%) acetone in water (40 mL). Suction drying at RT or vacuum-oven drying at 45°C gave Compound A monohydrate form III as a white solid.

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WO2015095430

Example 24: Ring Closing Metathesis

To a 50 mL 2-neck RB flask with reflux condenser and needle for N2 bubbling was charged the product of Example 20 (1.034 g, 0.869 mmol, 1.0 eq), toluene (20.68 ml, 20X), and the resulting solution was degassed with N2. Hoveyda-Grubbs 2nd generation catalyst (10.90 mg, 0.017 mmol) was charged to the pot, and the system was heated to 80°C with constant sparge of N2, with color change from green to reddish. The reaction was sampled (5 h) and assay by HPLC to be approximately 80% converted. The system was removed from the heat and allowed to stir at RT overnight under N2. The reaction was again assayed and deemed complete by HPLC. Toluene was removed by concentration and the resulting red oil was purified by gradient silica gel chromatography (50 g BlOTAGE SNAP Si gel column; loaded with DCM; eluted with 0 to 10% EtOAc in DCM over 10 column volumes; then 10 to 20% EtOAc in DCM over 3 column volumes; then hold; detect by TLC-UV) to yield a yellow solid, which was further slurried in EtOAc (3 mL) and hexanes (6 mL). The resulting slurry was filtered and washed with 25% EtOAc in hexanes (6 mL) to yield the product (445 mg, 0.754 mmol, 87% yield) as a white solid.

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http://anewmerckreviewed.wordpress.com/2013/04/23/okay-trivial-pursuit-will-the-real-mk-5172-please-stand-up/

Synthesis of MK-5172_NS3 protease inhibitor_Hepatitis C_Merck 默沙东丙型肝炎药物MK-5172的的化学合成

Merck reported interim data from the Phase 2 C-WORTHY study in April 2014 at the International Liver Congress (ILC) in London that evaluated the efficacy and safety of its two-drug regimen based on NS3/4A protease inhibitor MK-5172 and NS5A replication complex inhibitor MK-8742, given with or without ribavirin, in GT1 HCV patients with cirrhosis. The once-daily single pill (without ribavirin) showed a 98% SVR12 (12-week sustained virologic response) in genotype-1, treatment-naive patients. Merck will start the phase III clinical trials (NCT02105688NCT02105662NCT02105467 andNCT02105701) for the combination in June 2014.

 

MK-5172 is a novel, competitive inhibitor of the HCV NS3/4a protease with selective, potent in vitro activity against a broad range of HCV genotypes (GTs) and known viral variants that are resistant to other protease inhibitors in development.
MK-5172 is a Next Generation HCV NS3/4a Protease Inhibitor with a Broad HCV Genotypic Activity Spectrum and Potent Activity Against Known Resistance Mutants, in Genotype 1 and 3 HCV-Infected Patients. MK-5172 exhibits excellent selectivity over other serine proteases such as elastase and trypsin (no measurable inhibition), and shows only modest inhibitory potency with chymotrypsin (IC50 = 1.5 µM; 75,000-fold selective). In the genotype 1b replicon assay, MK-5172 potently inhibits viral replication (IC50 = 2 nM) and demonstrates a modest shift in the presence of 50% NHS (EC50 = 9.5 nM). In vitro, MK-5172 inhibits the NS3/4A enzyme from genotypes 1b, 2a, 2b, and 3a with Ki values of <0.02, 0.15, 0.02, and 0.7 nM, respectively. The genotype 2a replicon is also potently inhibited by MK 5172 (EC50 = 5 nM).
Kuethe J, * Zhong Y.-L, * Yasuda N, * Beutner G, Linn K, Kim M, Marcune B, Dreher SD, Humphrey G, Pei T. Merck Research Laboratories, Rahway, USA
Development of a Practical, Asymmetric Synthesis of the Hepatitis C Virus Protease Inhibitor MK-5172.Org. Lett. 2013;
15: 4174-4177
SignificanceNotify Users About this Post

MK-5172 is a hepatitis C virus protease inhibitor. Key steps in the synthesis depicted are (1) the regioselective SNAr reaction of dichloroquinoxaline A with prolinol derivative B and (2) construction of the 18-membered macrocycle ­using a macrolactamization (F → G).

Comment

The medicinal chemistry route to MK-5172 is based on a ring-closing metathesis strategy (S. Harper et al.ACS Med. Chem. Lett. 2012, 3, 332). The best regioselectivity (20:1) and minimization of double substitution in the SNAr reaction of A with B was achieved using 1,8-diaza­bicyclo[5.4.0]undec-7-ene (DBU) as the base in polar solvents such as DMSO, NMP, or DMAc.

 

SYNTHESIS, THESIS PROCEDURES, NMR see………..http://www.allfordrugs.com/2015/07/31/mk-5172-grazoprevir/

/////////////http://www.allfordrugs.com/2015/07/31/mk-5172-grazoprevir/

 

Want to know everything on vir series

click

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AND

http://medcheminternational.blogspot.in/p/vir-series-hep-c-virus.html

FALDAPREVIR


FALDAPREVIR

801283-95-4

(1R,2S)-1-{[(2S,4R)-4-[{8-bromo-7-methoxy-2-[2-(2-methylpropanamido)-1,3-thiazol-4-yl]quinolin-4-yl}oxy]-1-[(2S)-2-{[(cyclopentyloxy)carbonyl]amino}-3,3-dimethylbutanoyl]pyrrolidine-2-carboxamido]-2-ethenylcyclopropane-1-carboxylic acid

Boehringer Ingelheim (Originator)

BI-201335 is an HCV NS3 protease inhibitor awaiting approval in the E.U. by Boehringer Ingelheim for the treatment of chronic hepatitis C, in combination with pegylated Interferon and ribavirin.

Faldaprevir (formerly BI 201335) is an experimental drug for the treatment of hepatitis C. It is being developed by Boehringer-Ingelheim and is currently in Phase III trials.[1]

Faldaprevir is a hepatitis C virus protease inhibitor.

Faldaprevir is being tested in combination regimens with pegylated interferon and ribavirin, and in interferon-free regimens with other direct-acting antiviral agents including BI 207127.

Data from the SOUND-C2 study, presented at the 2012 AASLD Liver Meeting, showed that a triple combination of faldaprevir, BI 207127, and ribavirin performed well in HCV genotype 1b patients.[2] Efficacy fell below 50%, however, for dual regimens without ribavirin and for genotype 1a patients.

Phase II clinical trials are also ongoing for the treatment of patients with chronic genotype-1a hepatitis C virus (HCV) infection, in combination with PPI-668 and BI-207127.

In 2007, fast track designation was assigned to the compound in the U.S. for the treatment of chronic genotype-1 hepatitis C (HCV).

Protease inhibitors that are active against NS3/4a are a fertile area of research, not least because of the early promise shown by the two already-approved agents

Faldaprevir

Protease inhibitors that are active against NS3/4a are a fertile area of research. Boehringer Ingelheim’s compound faldaprevir is currently in Phase III trials.1 In one 24-week trial in 429 treatment-naïve patients with genotype-1 hepatitis C infection, subjects were given standard peg-interferon and ritonavir therapy plus placebo, or standard therapy plus either 120mg or 240mg of faldaprevir either with or without a three day lead-in of standard therapy alone, or standard therapy plus the higher dose of faldaprevir.

ADDN LIT

Discovery of a potent and selective noncovalent linear inhibitor of the hepatitis C virus NS3 protease (BI 201335)

J Med Chem 2010, 53(17): 6466

WO 2010033444

WO 2004103996

US6323180 Aug 5, 1999 Nov 27, 2001 Boehringer Ingelheim (Canada) Ltd Hepatitis C inhibitor tri-peptides
US7514557 * May 23, 2005 Apr 7, 2009 Boehringer Ingelheim International Gmbh Process for preparing acyclic HCV protease inhibitors
US7585845 * May 20, 2004 Sep 8, 2009 Boehringer Ingelheim International Gmbh Hepatitis C inhibitor compounds
US20050020503 * May 20, 2004 Jan 27, 2005 Boehringer Ingelheim International Gmbh Hepatitis C inhibitor compounds
US20120059033 Mar 9, 2011 Mar 8, 2012 Boehringer Ingelheim International Gmbh Crystalline Salts of a Potent HCV Inhibitor
USRE40525 Sep 30, 2005 Sep 30, 2008 Boehringer Ingelheim (Canada) Ltd. Hepatitis C inhibitor tri-peptides
WO2000009543A2 Aug 9, 1999 Feb 24, 2000 Boehringer Ingelheim Ca Ltd Hepatitis c inhibitor tri-peptides
WO2004087741A1 Mar 25, 2004 Oct 14, 2004 Boehringer Ingelheim Int Crystalline phases of a potent hcv inhibitor
WO2004103996A1 May 19, 2004 Dec 2, 2004 Boehringer Ingelheim Int Hepatitis c inhibitor compounds
WO2011112761A1 Mar 10, 2011 Sep 15, 2011 Boehringer Ingelheim International Gmbh Crystalline salts of a potent hcv inhibitor

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US8232293

Figure US08232293-20120731-C00011

EXAMPLES Example 1 Preparation of Quinoline Starting Material Compound 11

Figure US08232293-20120731-C00006

Step 1

The dianion of amide 1 (prepared exactly as described above, from 1.00 g amide 1) was cooled to −78° C., then 2.19 mL perfluorooctyl bromide (8.46 mmol, 1.75 eq.) was added dropwise via syringe over 5 minutes. The dark-colored reaction mixture was then placed in a −10° C. bath. After two hours, 10 mL 1N HCl was cautiously added, and the mixture extracted with EtOAc (2×25 mL), dried (MgSO4), and the solvents removed in vacuo. The residue was then chromatographed on silica gel eluting with 4:1 Hexane:EtOAc to give 1.13 g bromoamide 5 (81%) as a colorless oil. 1H NMR (400 MHz, CDCl3) δ: 8.12 (br s, 1H), 8.04 (dd, J=1.3, 8.4 Hz, 1H), 7.24 (t, J=8.3 Hz, 1H), 6.63 (dd, J=1.3, 8.3 Hz, 1H), 3.87 (s, 3H), 1.33 (s, 9H). 13C NMR (100 MHz, CDCl3) δ: 176.57 (s), 155.74 (s), 136.98 (s), 128.34 (d), 113.63 (d), 106.86 (d), 103.07 (s), 56.26 (q), 40.20 (s), 27.45 (q).

Step 2

0.25 g bromoamide 5 (0.87 mmol, 1 eq.), 2.0 mL con. HCl (24 mmol, 28 eq.), and 1.0 mL diglyme were heated at 100° C. for 24 hours. The mixture was then cooled and filtered (product). The filtrate was evaporated in vacuo using H2O to azeotropically remove all solvents. The residue was triturated with EtOAc to cause precipitation of additional product, which was also filtered. The combined solids were dried to give 0.16 g (77%) of bromoaniline 6.HCl as a light brown solid. 1H NMR (400 MHz, CDCl3) δ: 7.09 (t, J=8.1 Hz, 1H), 6.61 (d, J=8.0 Hz, 1H), 6.47 (d, J=8.1 Hz, 1H), 3.84 (br s, 2H), 3.77 (s, 3H).

Step 3

Bromoanisidine.HCl (5.73 g, 24.0 mmol), Aluminumtrichloride (3.52 g) and chlorobenzene (15.0 mL) are charged into an oven dried 100 mL three necked flask at rt (temperature rise to 30° C.). The resulting mixture is then stirred for 10 min then cooled to 0-5° C. followed by slow addition of acetonitrile (1.89 mL, 36.0 mmol) followed by addition of BCl(2.82 g), transferred as gas (or liquid) into the reaction mixture, keeping the temperature below 5° C. The resulting mixture is then stirred at rt for 20 min then heated to 85-100° C. for 16 h. HPLC indicate completion of the reaction (SM<0.5% at 220 nm). The mixture is cooled down to 50° C. then Toluene (15 mL) was added followed by slow addition of IPA (11.1 mL) then slow addition of water (32 mL) at 50° C. The resulting mixture stirred for additional 2 h at this temperature then 3 g Celite was added and the stirred mixture cooled to rt. Filtration then wash of the organic fraction with water 1×15 mL, 2×15 m: 5% NaHCO3, 1×15 mL water then concentration under reduced pressure provided 3.92-4.4 g of the desired product in 68-72% isolated yield. 1H NMR (400 MHz, CDCl3) δ: 7.72 (d, J=9.0 Hz, 1H), 7.1 (br s, 2H), 6.28 (d, J=9.1 Hz, 1H), 3.94 (s, 3H), 2.55 (s, 3H).

Step 4

Oxalyl chloride (8.15 mL) is added dropwise to the cold mixture (10±5° C.) of Thiazole acid 8 (20.18 g) is dissolved in THF (300 mL) and DMF (300 μL) over a period of ˜5 min keeping the internal temperature at 10±5° C. The reaction mixture becomes yellow and homogenous. The cooling bath is removed and the mixture is allowed to reach ambient temperature over a period of ˜30 min. Gas evolution is observed. The mixture is stirred at ambient temperature for 30 min to 1 hour. A solution of aniline 7 (19.8 g), DMAP (140 mg) and THF (35 mL) was added at 10±5° C. Et3N (13.2 mL) was added in portions at 10±5° C. over a period of 10 min. The ice bath was removed and mixture was heated to 65±2° C. and stirred overnight (18 h). The mixture was allowed to reach ambient temperature, diluted with EtOAc (150 mL) and washed with water (150 mL). NaHCO3(5%, 225 mL) was added to the organic portion and the mixture was stirred at ambient temperature for 30 min. The organic portion was concentrated under reduced pressure at approx. 40° C. EtOAc (150 mL) was added to the resulting material and the residual water was removed and the mixture was concentrated under reduced pressure at approx. 40° C. (to azeotrope water). EtOAc (94 mL) was added and the resulting slurry was stirred for 2-6 h and filtered. The solid was washed with EtOAc (30 mL) followed by heptane (30 mL) and air dried for 1 h to give the desired product in 70% yield.

1H NMR (400 MHz, CDCl3) δ: 1.32 (d, 6H, J=7.8 Hz), 2.58 (s, 3H), 2.65-2.72 (m, 1H), 3.98 (s, 3H), 6.83 (d, 1H, J=8.7 Hz), 7.70 (d, 1H, J=8.7 Hz), 7.86 (s, 1H), 8.98 (bs, 1H), 10.13 (bs, 1H).

Step 5

In a 2 L flask was placed potassium t-butoxide (112 g). Dry DME was added at room temperature (exothermic: temperature went up to 35° C.). The resultant solution was heated to ca. 80° C., and amide (88 g) was added in 10 portions slowly so temperature was kept between 80-85° C. Upon completion, reaction mixture was stirred at 85° C. for 2 hours. Solid precipitated during the reaction. HPLC analysis indicated that the reaction was completed at this point (conversion: 100%). The reaction mixture was cooled to room temperature and then to 10° C. with a cool bath. Aqueous 2N HCl solution (ca. 500 ml) was added slowly so temperature was kept under 25° C. to quench the reaction mixture. pH was adjusted to 4-5. About 100 ml of water was added (Note: amount of water may need adjustment to facilitate filtration), and the resulting suspension was stirred at room temperature for 5-10 hours. Product was isolated by filtration, washing with THF and drying under vacuum. Yield: 81 g, 96% yield.

1H-NMR (400 M Hz, DMSO-d6): 1.14 (6H, d, J=6.8 Hz, i-Pr), 2.48 (1H, hept., J=6.8 Hz, i-Pr), 3.99 (3H, s, MeO), 6.75 (1H, s, H-3), 7.24 (1H, d, J=8.5 Hz, H-6), 8.10 (1H, d, J=8.5 Hz, H5), 8.22 (1H, s, H-5′), 9.87 (1H, s, OH), 12.40 (1H, s, amide NH).

Step 6

In a 100 ml flask was placed starting material quinoline (4.22 g) and dioxane (40 ml). POCl(4.6 g) was added, and the mixture was heated to 75° C. After 2 hours, HPLC showed the reaction finished (99.7% conversion). Reaction mixture was cooled to room temperature, and then poured to 100 ml saturated NaHCOsolution and 20 ml EtOAc. The resulting suspension was stirred for 3 hours. Product was isolated by filtration, washing with EtOAc and drying under vacuum. Yield: 4.0 g, 90.9%.

1H-NMR (400 M Hz, CDCl3): 1.14 (6H, d, J=6.8 Hz, i-Pr), 2.76 (1H, hept., J=6.8 Hz, i-Pr), 4.05 (3H, s, MeO), 7.68 (1H, d, J=8.5 Hz, H-6), 8.07 (1H, s, H-3), 8.13 (1H, s, H-5′), 8.20 (1H, d, J=8.5 Hz, H5), 12.30 (1H, s, amide NH).

Example 2 Preparation of Dipeptide Acid Compound 13 Starting Material

Figure US08232293-20120731-C00007

A 250 mL 3-neck flask with a thermocouple, nitrogen inlet, and magnetic stir bar was charged with N-cyclopentyloxy carbonyl-tert-L-leucine (20.0 g, 82.2 mmol, 1.0 eq.), 1-hydroxy-benzotriazole (12.73 g, 90.42 mmol, 1.1 eq), and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (17.33 g, 90.42 mmol, 1.1 eq.) The flask was purged with nitrogen, and the stiffing started. Anhydrous DMF (62 mL) was added to the flask and the mixture was stirred for 20 minutes at room temperature (about 24° C.). The reaction was mildly exothermic, the internal temperature rose to 29° C. Solid trans-4-hydroxyproline methyl ester HCl (14.93 g, 82.2 mmol, 1.0 eq) was added to the reaction in one portion. Using a syringe, diisopropyl ethyl amine (14.36 mL, 82.2 mmol, 1.0 eq) was added to the reaction dropwise over 25 min. The internal temperature rose to 34.5° C. from 29° C. The reaction was stirred for 1.75 h, forming 12. The reaction was then quenched with 0.1 M HCl (100 mL), the internal temperature rose to 34° C. The reaction was extracted three times with 75 mL of ethyl acetate, and the organic layers were combined. The organic layer was washed with 75 mL H2O, and 2×75 mL of sat. NaHCO3. The organic layer (about 235 mL) was transferred to a 500 mL flask fitted with a mechanical stirrer, shortpath distillation head, internal and external thermocouples, and distilled to minimal stirrable volume under house vacuum (˜110 mm Hg) below 35° C. internal temperature with an oil bath temperature of 40° C. To this crude mixture of 12 was then added tetrahydrofuran (150 mL) and it was distilled to minimum stirrable volume. Tetrahydrofuran (100 mL) was added to the flask, and it was again distilled to minimum stirrable volume. The distillation head was replaced with an addition funnel. Tetrahydrofuran, (100 mL) and methanol (50 mL) were added to the flask, and the solution stirred for about 15 minutes. A 3.2 M solution of LiOH (77 mL, 246.6 mmol, 3 eq.) was charged to the addition funnel, and added over 45 minutes. The temperature rose from 22° C. to 29° C., and the reaction mixture became slightly cloudy. The mixture was cooled in a cold water bath, then the reaction was quenched by slow (45 min.) addition of 4 M HCl (58-65 mL) to adjust the pH to 3.5, causing a slight increase in temperature to 27° C. The flask was fitted with a distillation head, and the methanol and tetrahydrofuran were removed by distillation at reduced pressure, with a bath temperature of 40° C., internal temperature below 30° C. The mixture was extracted twice with 150 mL of MTBE. The MTBE solution was concentrated at reduced pressure, (350 mmHg) to minimum stirrable volume. 50 mL of MTBE was added, it was removed by distillation, internal temp below 35° C. The reaction was a clear viscous liquid, 20 mL of MTBE was added, the mixture was heated to 50° C., solution was clear, the oil bath was turned off, and the solution cooled to rt, ˜24° C. over 1.5 h. To the resultant slurry was then added 60 mL MTBE, stirred 2 h, then the slurry was filtered, using ˜20 mL MTBE to transfer the mixture. The solid was then dried under vacuum at 35° C. to constant weight, 16.4 g (52%), to give the ⅓ MTBE solvate compound 13 as a colorless solid, m.p. 117-124° C.; αD=−58.6 (c 2.17, MeOH); 1H NMR (400 MHz, DMSO, major rotamer reported) δ: 6.76 (d, J=9.3 Hz, 1H), 5.15 (s, 1H), 4.92 (m, 1H), 4.31 (br s, 1H), 4.26 (t, J=8.3 Hz, 1H), 4.19 (d, J=9.3 Hz, 1H), 3.63 (m, 2H), 3.06 (s, 1H, (MTBE)), 2.08 (m, 1H), 1.87-1.48 (m, 9H), 1.09 (s, 3H, (MTBE)), 0.92 (s, 9H).

Example 3 Preparation of Tripeptide Acid Compound 16 Starting Material

Figure US08232293-20120731-C00008

In a 25 ml flask 14 was dissolved in 3 ml DMF. HOBt (149 mg, 1.1 mmol), EDC (211 mg, 1.1 mmol), 13 (290 mg, 1.0 mmol) and i-Pr2NEt (129 mg, 1.0 mmol) were added in the given order at room temperature. The resulting reaction mixture was stirred at room temperature overnight. The reaction mixture was poured into 15 ml aqueous NaHCOand extracted with ethyl acetate (20 ml). The organic layer was washed with HCl (0.5 N, 2×10 ml) and saturated aqueous NaHCO(10 ml). After removal of solvent by rotary evaporation, 15 was obtained as a white solid. 0.46 g (95% yield). 1H-NMR (400 M Hz, CDCl3): 0.96 (s, 9H), 1.35 (1H, dd, J=3.0, 4.5 Hz), 1.45-1.90 (m, 9H), 1.77 (1H, dd, J=3.0, 4.0 Hz), 2.00-2.09 (1H, m), 2.45-2.52 (1H, m), 3.02 (1H, br), 3.50 (1H, dd, J=11.0, 3.0 Hz), 3.58 (3H, s), 3.99 (1H, d, J=11.0 Hz), 4.18 (1H, d, J=9.0 Hz), 4.43 (1H, br), Hz), 4.63 (1H, t, J=8.0 Hz), 4.93-5.00 (1H, m), 5.04 (1H, dd, J=10.5, 2.0 Hz), 5.20 (1H, d, J=18.0 Hz), 5.20-5.25 (1H, m), 5.65-5.77 (1H, ddd, J=18.0, 10.5, 2.0 Hz), 7.78 (1H, br) ppm.

320 mg ester 15 (0.667 mmol, 1 eq.) was dissolved in 6.7 mL THF+3.4 mL MeOH at ambient temperature under N2. To this solution was then added 3.34 mL 1.6 M LiOH (5.34 mmol, 8 eq.) dropwise over 5 minutes. After 1.5 hours, the solvents were removed in vacuo, and the residue diluted with 15 mL EtOAc+10 mL sat’d NaCl, then 1N HCl was added until pH 3.45 was reached. The phases were separated and the aqueous phase reextracted with 15 mL EtOAc. The combined EtOAc layers were washed with H2O (1×50 mL), dried (MgSO4), and the solvents removed in vacuo to give an oil. The oil was azeotroped with MTBE (1×15 mL), and the residue dried under high vacuum to give 320 mg of 16 (100%) as a colorless foam. Exact mass calc’d for C23H35N3O7: 465.25. Found (ES−): 464.29; 1H NMR (400 MHz, DMSO, major rotamer reported) δ: 12.40 (br s, 1H), 8.49 (s, 1H), 6.77 (d, J=8.2 Hz, 1H), 5.71 (m, 1H), 5.22-4.85 (m, 4H), 4.36-4.10 (m, 3H), 3.80-3.21 (m, 4H), 2.00-1.42 (m, 11H), 0.92 (s, 9H).

Example 4 Dipeptide SNAr Approach to Amorphous Compound (1)

Figure US08232293-20120731-C00009

SNAr Protocol 1: A 100 mL 3-neck round bottom flask was charged with 1.93 g 13 (5.00 mmol, 1 eq.), then evacuated/Ar filled (3×), then 17.0 mL DMSO was added via syringe to give a clear, colorless solution. The flask was again evacuated/Ar filled (3×), then 2.53 g t-BuOK (22.5 mmol, 4.5 eq.) was added neat, at once. An exotherm to a maximum of 31.5° C. was observed. The flask was evacuated/Ar filled (3×), then stirred under house vacuum (˜60 mm) for one hour, and some foaming (-t-BuOH) was observed. The vacuum was relieved to Ar, then 2.20 g 11 (5.00 mmol, 1 eq.) was added neat, at once. An exotherm to 28.6° C. was observed. The flask was evacuated/Ar filled (3×), then stirred under house vacuum protected from light at ambient temperature. After 6.5 h the vacuum was relieved to Ar and a sample removed for HPLC, which showed <2% unreacted 11. The flask was then cooled in a cold water bath to 18° C., and 1.72 mL glacial HOAc (30 mmol, 6 eq.) was then added via syringe over ˜10 minutes. An exotherm to 20.5° C. was observed. The mixture was stirred for 10 minutes, then added dropwise over 15 minutes into a second flask containing a well-stirred solution of 30 mL pH 3.5H2O (˜0.001M HCl) at 18° C., causing a precipitate to form immediately, and giving an exotherm to 21.0° C. 2.0 mL DMSO was used to wash the residue into the aqueous mixture, followed by a wash of 5.0 mL ˜0.001M HCl. The resulting suspension was stirred for 15 minutes, then 30 mL of a 1:1 mixture of EtOAc:MTBE was added, and the mixture agitated vigorously for 15 minutes. Agitation was stopped and the phases were allowed to separate. Rapid phase separation and formation of 2 clear phases with no rag layer was seen. The lower aqueous phase was then reextracted with 30 mL of 1:1 EtOAc:MTBE (same fast separation), and the organic extracts were combined and saved. The aqueous phase was discarded as waste.

The organic solution was then washed with H2O (3×30 mL), again all extractions gave rapid separation of phases and no rag layer, then the EtOAc was distilled to minimal stirrable volume. The residue was then azeotroped with 30 mL THF (2×), again distilling to minimal stirrable volume. The resultant slurry of crude 18 was used immediately in the peptide coupling. Exact mass calc’d for C34H42BrN5O8S: 759.19. Found (MS−): 757.92.

SNAr Protocol 2: 1.00 g 13 (2.59 mmol, 1 eq.) and 1.35 g 11 (2.59 mmol, 1 eq.) were charged to a dry flask. The flask was then evacuated/Ar filled (3×), then 10 mL dry DMSO was added via syringe. The flask was again evacuated/Ar filled (3×), then cooled to 19° C. with a cold water bath. To this mixture was then added a 2M solution of KDMO/heptane (5.71 mL, 11.7 mmol, 4.5 eq.) dropwise over 30 minutes. After six hours, HPLC showed the reaction as complete. The reaction was quenched with 0.89 mL HOAc (6 eq.), and added slowly to 25 mL stirring H2O, causing a precipitate to form. The mixture was then extracted with IPAc (2×25 mL). The combined IPAc phases were washed with H2O (1×25 mL), dried (MgSO4), and the solvents removed in vacuo to give a solid, which was azeotroped with MeCN (1×25 mL), and then diluted with heptane to give a slurry. The slurry was filtered and dried to give 1.80 g 18 (91%).

Peptide Coupling Protocol 1: To the THF slurry of crude 18 from SNAr Protocol 1 (taken as 5.00 mmol, 1 eq.) under Ar at ambient temperature in a flask protected from light was added 1.72 g 14 (5.5 mmol, 1.1 eq.) and 25 mL THF. The solution was then cooled to 5° C. under Ar, then 0.958 mL DIEA (5.50 mmol, 1.1 eq.) was added dropwise via syringe over 5 minutes. 5 minutes after the DIEA addition was completed, 0.85 g HOBT hydrate (6.00 mmol, 1.2 eq.), and 1.05 g EDC (5.50 mmol, 1.1 eq.) was then added neat, at once. The flask was then removed from the cold bath and the resultant mixture was then stirred at ambient temperature under Ar for 4 hours. A sample was withdrawn for HPLC which showed <2% unreacted 18 remained. The mixture was cooled to 5° C., then 40 mL 0.1N HCl was added dropwise via addition funnel over 5 minutes, followed by 40 mL EtOAc. The mixture was well agitated for 15 minutes, then agitation was stopped and the phases were allowed to separate. The lower aqueous phase was then reextracted with 40 mL EtOAc and the organic phases were combined and saved. The aqueous phase was discarded as waste. The organic solution was then washed with H2O (1×40 mL), sat’d NaHCO(2×40 mL), and again H2O (1×40 mL), then distilled to minimal stirrable volume. The residue was then azeotroped with MTBE (2×40 mL), and again distilled to minimal stirrable volume. The residue was dried under high vacuum to give 4.70 g of crude 19 as an orange solid, with HPLC purity of 78.3%. This material was then chromatographed on silica gel eluting with 2:1 EtOAc:Hexane to give 3.01 g (68% over 2 steps) pure 19 as a yellow powder. Exact mass calc’d for C41H51BrN6O9S: 882.26, MS+: 883.30. 1H NMR (400 MHz, DMSO, major rotamer reported) δ: 12.32 (s, 1H), 8.69 (s, 1H), 8.14 (d, J=9.2 Hz, 1H), 8.03 (s, 1H), 7.45 (s, 1H), 7.33 (d, J=9.4 Hz, 1H), 6.97 (d, J=8.6 Hz, 1H), 5.65 (m, 1H), 5.40 (s, 1H), 5.20 (dd, J=1.5, 17 Hz, 1H), 5.06 (dd, J=1.6, 10.2 Hz, 1H), 5.56 (s, 1H), 4.46 (m, 1H), 4.37 (d, J=9 Hz, 1H), 4.08 (m, 1H), 3.99 (s, 3H), 3.90 (m, 1H), 3.56 (s, 3H), 2.81 (m, 1H), 2.51 (m, 1H), 2.25 (m, 1H), 2.07 (m, 1H), 1.70-1.32 (m, 7H), 1.30 (m, 3H), 1.15 (d, J=8.1 Hz, 6H), 0.95 (s, 9H).

Peptide Coupling Protocol 2: A 5 L 4-neck RBF fitted with mech. stirrer, addition funnel, and thermocouple was charged with 69.57 g 14 (222 mmol, 1.3 eq.), then evacuated/Ar filled (3×). To this was then added a 200 mL THF solution of 18 (contains 129.85 g 171 mmol, 1 eq.), then 523 mL THF was charged to bring the final THF volume to 1 L. The mixture was then cooled to 4.0° C. under Ar. 38.67 mL DIEA (222 mmol, 1.3 eq.) was then added dropwise via addition funnel over 10 minutes, as the internal temperature fell to 2.4° C. The mixture was aged 5 minutes, then 29.98 g HOBT H2O (222 mmol, 1.3 eq.) was added, followed by 42.57 g EDC (222 mmol, 1.3 eq.). The internal temperature was then 3.6° C. The bath was then removed. The internal temperature rose to 20.5° C. over 90 minutes. 4 h after the EDC addition was completed, HPLC showed the reaction was complete. The mixture was cooled to 4.0° C., then 750 mL 0.1N HCl was added over 30 minutes via addition funnel, giving an exotherm to 9.5° C. To this mixture was then added 250 mL sat’d NaCl, followed by 1 L IPAc. After 5 min. vigorous stirring, the mixture was added to a separatory funnel, and the phases were separated. The lower aq. phase was then reextracted with 500 mL IPAc, and the IPAc phases combined. These were then washed successively with H2O (1×1 L), sat’d NaHCO(1×1 L), and then H2O (1×1 L). The mixture was then mech. stirred for 12 h to precipitate quinoline 7. The mixture was then filtered through a medium-fritted funnel, and the filtrate distilled until minimal stirrable volume was reached. The residue was then azeotroped with MTBE (2×400 mL), and again distilled to minimal stirrable volume. The residue was dried under high vacuum to give 128 g of 19 as a yellow solid, with HPLC purity of 89%.

140 mg 19 (0.158 mmol, 1 eq.) was dissolved in 1.6 mL THF+0.80 mL MeOH at ambient temperature under N2. To this solution was then added 0.79 mL 1.6 M LiOH (1.27 mmol, 8 eq.) dropwise over 5 minutes. After 1.5 h, the organic solvents were removed in vacuo, and the residue diluted with 10 mL EtOAc+10 mL sat’d NaCl. The pH was then adjusted to 5.75 with 1N HCl. The mixture was agitated vigorously for one hour, then the phases were separated. The aqueous phase was reextracted with 10 mL EtOAc. The combined EtOAc phases were then washed with H2O (2×25 mL), dried (MgSO4, and the solvents removed in vacuo to give 125 mg of Compound (1) (91%) as an amorphous yellow powder.

Example 5 Tripeptide SNAr Approach to Amorphous Compound (1)

Figure US08232293-20120731-C00010

233 mg tripeptide acid 16 (0.50 mmol) was charged to a flask, then the flask was evacuated/Ar filled (3×). 1.7 mL DMSO was then added, and the mixture evacuated/Ar filled (3×). The mixture was then cooled in a cold water bath, then 317 mg t-BuOK (2.82 mmol, 5.63 eq.) were added. The flask was again evacuated/Ar filled (3×), then stirred under 60 mm vacuum for one hour. 220 mg quinoline 11 (0.50 mmol, 1 eq.) was then added, and the flask evacuated/Ar filled (3×), then stirred under 60 mm vacuum in the dark at ambient temperature for 3 hours. 0.30 mL HOAc was then added, then the resulting solution was added to 25 mL 0.001 M HCl, causing a precipitate to form. The slurry was filtered, washing the solids with 25 mL H2O. The solid was dried under Nfor 2 hours, then chromatographed on silica gel eluting with EtOAc to give 226 mg (52%) of Compound (1) as an amorphous yellow solid.

Additional methods for preparing amorphous Compound (1) can be found in U.S. Pat. Nos. 6,323,180, 7,514,557 and 7,585,845, which are herein incorporated by reference.

Example 6 Preparation of Type A of Compound (1)

Amorphous Compound (1) (Batch 7, 13.80 g) was added to a 1000 ml three neck flask. Absolute ethanol (248.9 g) was added to the flask. While stirring, the contents of the flask were heated at 60 degrees C./hr to ˜74 degrees C. (Solids do not dissolve at 74 degrees C.). Water (257.4 g) was then added linearly over 4 hr to the resulting slurry while stirring and maintaining the temperature at 74 degrees C. After the water addition was complete, the temperature was reduced linearly to ambient temperature at 8 degrees C./hr and then held at ambient temperature for 6 hrs while stiffing. The resulting solids were collected by filtration and washed with 50 ml of 1/1 (w/w) EtOH/Water. The wet solids were dried on the funnel for 30 minutes by sucking Nthrough the cake. (XRPD analysis on this sample indicates that the pattern is similar to the EtOH solvate). The solids were then dried at 65-70 degrees C. under vacuum (P=25 in Hg) and a nitrogen bleed for 1.5 hr. The resulting solids (12.6 g, 95.5% corrected yield) were confirmed by XRPD as being Type A Compound (1).

The unique XRPD pattern and DSC curve of Type A Compound (1) is shown in FIGS. 1 and 2.

Example 7 Preparation of the Sodium Salt of Compound (1)—Method 1

2.1 g of amorphous sodium salt of Compound (1) and 8.90 g of acetone was added to a vial and stirred at ambient temperature for 3 hr. The slurry was filtered off mother liquors and the resulting solids were dried for 20 minutes under nitrogen flow for 20 minutes. 1.51 g of crystalline sodium salt of Compound (1) as solids was collected.

Example 8 Preparation of the Sodium Salt of Compound (1)—Method 2

15.6 g of Type A of Compound (1), 175 ml of acetone and 3.6 ml of water was added to a 250 ml reactor and heated to 53 degrees C. to dissolve the solids. 900 ul of 10.0 N NaOH was added to reactor and the solution was seeded with Type A. The seeded solution was stirred at 53 degrees C. for 10 minutes. A second 900 ul portion of 10.0 N NaOH was added and the system was stirred at 53 degrees C. for 30 minutes over which a slurry developed. The slurry was cooled to 19 degrees C. at a cooling rate of 15 degrees C. per hour and held overnight at 19 degrees C. The final resulting slurry was filtered and the wet solids were washed with 15 ml of acetone. Dried solids for 1 hr at 52 degrees C. under vacuum with a nitrogen flow and then exposed the solids to lab air for one hour. Collected 12.1 g of Compound (1) crystalline sodium salt solids.

Example 11 Preparation of the Sodium Salt of Compound (1)—Method 5

At room temperature a solution of sodium ethoxide in ethanol (21 weight %; 306 ml) was added to a solution of Compound (1) (745 g) in THF (2000 ml) and water (76.5 ml) while stiffing. After stiffing for 30 minutes, the mixture was filtered and the filter was washed with THF (85 ml). The resulting solution was warmed to 65° C. and treated with filtered butyl acetate (6640 ml, optionally pre-warmed to 65° C.) within 30 minutes. Seeding crystals (0.50 g) were added, and the mixture was stirred at 65° C. for 2 hours, while crystallization starts after about 30 minutes. The suspension was cooled to 50° C. within 1 hour and stirred at this temperature for an additional hour. The title compound was isolated by filtration, washed with filtered butyl acetate (765 ml, optionally pre-warmed to 50° C.) and dried at 65° C. for about 16 h giving Compound (1) crystalline sodium salt (˜725 g).

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Patent Filing date Publication date Applicant Title
US8399484 Sep 16, 2009 Mar 19, 2013 Boehringer Ingelheim International Gmbh Combination therapy for treating HCV infection
US8530497 Mar 9, 2011 Sep 10, 2013 Boehringer Ingelheim International Gmbh Crystalline salts of a potent HCV inhibitor
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Biota Reports That Laninamivir Octanoate is Approved for the Prevention of Influenza in Japan


Laninamivir

(4S,5R,6R)-5-acetamido-4-carbamimidamido-6-[(1R,2R)-3-hydroxy-2-methoxypropyl]-5,6-dihydro-4H-pyran-2-carboxylic acid

Formula C13H22N4O7 
Mol. mass 346.33638 g/mol

cas 203120-17-6,

Laninamivir (L174000) prodrug; a novel long-acting neuraminidase inhibitor.

laninamivir octanoate

472.53254, C21H36N4O8,   cas no 203120-46-1, R-125489, CS-8958 

Daiichi Sankyo (Originator)

R-118958 is a potent, long-acting neuraminidase inhibitor (LANI) approved and launched in 2010 in Japan as an inhalable formulation for the treatment of influenza A and influenza B in adults and pediatric patients. In 2013 the product was approved in Japan for the prevention of influenza A and influenza B.

5-(Acetylamino)-4-[(aminoiminomethyl)amino]-2,6-anhydro-3,4,5-trideoxy-7-O-methyl-D-glycero-D-galacto-non-2-enonic Acid 9-Octanoate
(2R,3R,4S)-3-Acetamido-4-guanidino-2-[(1R,2R)-2-hydroxy-1-methoxy-3-(octanoyloxy)propyl]-3,4-dihydro-2H-pyran-6-carboxylic Acid
(4S,5R,6R)-5-Acetamido-4-guanidino-6-[(1R,2R)-2-hydroxy-1-methoxy-3-(octanoyloxy)propyl]-5,6-dihydro-4H-pyran-2-carboxylic Acid
CS 8958

ATLANTA, Dec. 20, 2013 (GLOBE NEWSWIRE) — Biota Pharmaceuticals, Inc.
(Nasdaq:BOTA) (“Biota” or the “Company”) today reported that Daiichi Sankyo Company, Limited (“Daiichi Sankyo”) has been granted regulatory approval in Japan to manufacture and market Inavir(R) Dry Powder Inhaler 20mg (generic name laninamivir octanoate) for the prevention of influenza A and B. Inavir(R) was successfully developed and launched by Daiichi Sankyo in Japan for treatment of influenza A and B viruses in October, 2010. Biota is developing laninamivir octanoate outside of Japan for the treatment of influenza, and is currently conducting a large, multi-national Phase 2 trial of laninamivir octanoate in adults infected with influenza. In 2003, the Company and Daiichi Sankyo entered into a collaboration and license agreement to develop long-acting neuraminidase inhibitors, including laninamivir octanoate, and in March 2009, the parties entered into a commercialization agreement, pursuant to which Daiichi Sankyo obtained exclusive marketing rights to laninamivir octanoate in Japan.http://www.pharmalive.com/biota-flu-drug-okd-in-japan

Laninamivir (CS-8958) is a neuraminidase inhibitor which is being researched for the treatment and prophylaxis of Influenzavirus A and Influenzavirus B.[1] It is currently in Phase III clinical trials. [2]

Laninamivir was approved for influenza treatment in Japan in 2010 and is currently marketed under the name “Inavir” by Daiichi Sankyo. Biota Pharmaceuticals [3] and Daiichi Sankyo co-own Laninamivir. On 1st April 2011, BARDA awarded up to an estimated U$231m to Biota Pharmaceuticals (Formerly Biota Holdings Ltd) wholly owned subsidiary, Biota Scientific Management Pty Ltd, for the advanced development of Laninamivir in the US. [4]

patent

8-13-2010
DRUG FOR TREATMENT OF INFLUENZA
WO 2013089168
WO 2008126943

The recent flu scares – first H5N1 bird flu and then H1N1 swine flu – transformed Roche’s neuraminidase inhibitor Tamiflu (oseltamivir) into a household name, along with GSK’s Relenza (zanamivir). Both of these require twice-daily dosing, and the orally available oseltamivir is the first choice, but resistance is starting to appear.

A new neuraminidase inhibitor, laninamivir, is being developed by Daiichi Sankyo.5 When administered as the octanoate prodrug form, it appears that a single dose might be sufficient to treat influenza, weekly doses could be preventative, and it is active against extremely pathogenic H5N1 strains.

Laninamivir octanoate

In a double blind, randomised, placebo-controlled Phase I study in 76 healthy male volunteers, subjects were given inhaled single doses of 5, 10, 20, 40, 80 or 120mg of the prodrug, or twice-daily doses of 20 or 40mg for three days.6 No adverse events were observed, and while the prodrug disappeared from the plasma with a half-life of about two hours, the laninamivir itself was much more slowly eliminated, with a half-life of the order of three days, suggesting the potential for giving long-lasting activity against influenza.

In another Phase I trial, a total of 20 healthy subjects with renal function ranging from normal to severely impaired were given single inhaled 20mg doses of the prodrug.7 The degree of renal impairment did not affect the maximum concentration or the time to achieve it, but the half-life increased as renal function reduced. This indicates that the rate-limiting step for elimination is drug release rate to plasma from tissues rather than renal excretion. It was well tolerated, but systemic exposure increased with increasing renal impairment.

It has also been compared with oseltamivir in patients with influenza. A total of 186 children under 10 who had had febrile influenza symptoms for no longer than 36 hours were randomised to receive 20 or 40mg of laninamivir octanoate as a single inhalation or 2mg/kg oseltamivir orally twice a day for five days.8

The new drug gave a significant reduction, of 61 hours for the 40mg group and 66 for the 20mg group, in median time to illness alleviation compared with oseltamivir in those with oseltamivir-resistant H1N1 influenza A. However, there was no significant difference in the time to alleviation of illness with H3N2 influenza A, or influenza B.

The most common side-effects were gastrointestinal problems.

In a Phase III trial, a total of 1,003 adult patients with febrile influenza symptoms for no more than 36 hours were given similar doses to those in the trial in children.9 Median time to alleviation of illness was 73h for 40mg, 86h for 20mg, and 74h for oseltamivir, and the proportion of patients shedding virus at day 3 was significantly lower in the 40mg group than for those given oseltamivir.

  1.  Yamashita M, Tomozawa T, Kakuta M, Tokumitsu A, Nasu H, Kubo S (January 2009).“CS-8958, a prodrug of the new neuraminidase inhibitor R-125489, shows long-acting anti-influenza virus activity”Antimicrobial Agents and Chemotherapy53 (1): 186–92.doi:10.1128/AAC.00333-08PMC2612152PMID18955520.
  2.  Hayden F (January 2009). “Developing new antiviral agents for influenza treatment: what does the future hold?”. Clinical Infectious Diseases. 48. Suppl 1 (S1): S3–13.doi:10.1086/591851PMID19067613.
  3. http://www.biotapharma.com
  4. http://www.biotapharma.com/?page=1021001&subpage=1021019

5. T. Honda et al. Synthesis and in vivo influenza virus-inhibitory effect of ester prodrug of 4-guanidino-7-O-methyl-Neu5Ac2en, Bioorg Med Chem Lett 2009, 19(11): 2938

6. H. Ishizuka et al. J. Clin. Pharmacol. 2010, 50, 1319

7. H. Ishizuka et al. J. Clin. Pharmacol. 2010, epub ahead of print, doi 10.1177/0091270010361914

8. N. Sugaya and Y. Ohashi, Antimicrob. Ag. Chemother. 2010, 54, 2575

9 A. Watanabe et al. Clin. Inf. Dis. 2010, 51, 1167

A new route toward 2-acetamido-4-O-methyl-2-deoxy-D-mannopyranose from a Ferrier derivative of tri-O-acetyl-D-glucal, which contributes to aldolase-catalyzed synthesis of laninamivir (CS-8958)
Tetrahedron 2013, 39(37): 7931

Infection of poultry with H5N1 avian influenza virus has been expanding since 2003 in wide areas including Asia, Europe and Africa. Humans infected with this virus have been found not only in Asia but also in Middle East and Africa. If a new type of H5N1 influenza virus has appeared and its infection has started, it is believed that the infection will rapidly expand to cause a worldwide spread (i.e., influenza pandemic) because most people do not possess immunity against that virus and influenza viruses spread via droplet infection and airborne infection. More than half of human patients infected with H5N1 influenza virus have died so far. Thus, the virus is highly pathogenic. It is known that three influenza pandemics, the Spanish Flu, the Asian Flu and the Hong Kong Flu, occurred in the 20th century. In the Spanish Flu which caused the largest number of patients, it is estimated that about 20-40 million people died in the world and about 0.5 million people in Japan.

According to a report from Japanese Ministry of Health, Labour and Welfare made in November, 2005, if a new type influenza virus has spread, the number of patients who will consult medical doctors in Japan as a result of infection with that virus is estimated about 18-25 million. Further, when the pathogenicity of that new type influenza virus is severe, the number of inpatients is estimated about 0.2 million while the number of dead is estimated about 0.64 million. Therefore, not only health hazard but also significant influences upon social activities are feared.

Thus, a new type influenza can cause a highly severe disease. Early development of effective therapeutics is demanded.

Although it is reported that zanamivir (in particular, zanamivir hydrate) and oseltamivir (in particular, oseltamivir phosphate or oseltamivir carboxylate) which are influenza therapeutics with neuraminidase inhibitory activity show an inhibitory activity against H5N1 influenza virus, compounds with more excellent activity are desired (Non-Patent Document 1 or 2). Further, H5N1 influenza virus strains against which oseltamivir does not show any inhibitory activity (i.e., oseltamivir resistant virus strains) have been reported. Compounds which possess an inhibitory activity against these oseltamivir resistant H5N1 influenza virus strains are desired (Non-Patent Document 1 or 2).

Compounds represented by formula (I) are known to be useful as influenza therapeutics with neuraminidase inhibitory activity (Patent Documents 1 to 3). However, it has not been reported that these compounds have an inhibitory activity against H5N1 influenza virus. Further, the structures of the compounds represented by formula (I) resemble the structure of zanamivir but are completely different from the structure of oseltamivir.

Non-Patent Document 1: Nature, 2005, vol. 437, p. 1108

Non-Patent Document 2: N. Engl. J. Med., 2005, vol. 353, (25):2667-72
Patent Document 1: U.S. Pat. No. 6,340,702 (Japanese Patent No. 3209946)
Patent Document 2: U.S. Pat. No. 6,451,766 (Japanese Patent Publication No. Hei 10-109981)
Patent Document 3: U.S. Pat. No. 6,844,363 (Japanese Patent Publication No. 2002-012590)

Figure US20100204314A1-20100812-C00004

………………………

US20100204314

Preparation Example 1 5-Acetamido-4-guanidino-9-O-octanoyl-2,3,4,5-tetradeoxy-7-O-methyl-D-glycero-D-galacto-non-2-enopyranosoic acid

Figure US20100204314A1-20100812-C00005

(1) Diphenylmethyl 5-acetamido-4-(N,N-bis-t-butyloxycarbonyl)guanidino-9-O-octanoyl-2,3,4,5-tetradeoxy-7-O-methyl-D-glycero-D-galacto-non-2-enopyranosoate (3.46 g, 4.1 mmol) disclosed in Example 35 (i) of U.S. Pat. No. 6,340,702 (Japanese Patent No. 3209946) was dissolved in methylene chloride (27 ml) and trifluoroacetic acid (14 ml). The resultant solution was stirred at room temperature overnight. The reaction solution was concentrated to dryness under reduced pressure, followed by three cycles of azeotropic distillation to dryness with toluene (5 ml). The resultant oily material was dissolved in ethyl acetate (10 ml). The solution was poured into a saturated aqueous solution of sodium hydrogencarbonate (50 ml). The pH of the resultant solution was adjusted to 8.5 by addition of 20% aqueous solution of sodium carbonate. Then, the solution was stirred at room temperature for 3 hr and its pH was adjusted to 5.0 with hydrochloric acid (3 ml), followed by stirring at room temperature for another 1 hr. The solution was further stirred for 1 hr while ice-cooling. Subsequently, precipitating crystals were suction filtered and vacuum dried for 10 hr at an external temperature of 50° C. The resultant crystals were left in the air for one day to thereby yield the subject compound as a hydrate crystal (0.97 g; yield 51%).

Infrared Absorption Spectrum (KBr) ν max cm−1: 3412, 2929, 2856, 1676, 1401, 1320, 1285, 1205, 1137, 722.

1H Nuclear Magnetic Resonance Spectrum (400 MHz, CD3OD) δ ppm: 5.88 (1H, d, J=2.5 Hz), 4.45 (3H, m), 4.27 (1H, dd, J=10.0 Hz, 10.0 Hz), 4.15 (1H, m), 3.47 (21-1, m), 3.42 (3H, s), 2.37 (2H, t, J=7.4 Hz), 2.10 (3H, s), 1.31 (2H, m), 1.20-1.40 (8H, m), 0.85-0.95 (3H, m).

13C Nuclear Magnetic Resonance Spectrum (100 MHz, CD3OD) δ ppm: 176.5, 173.7, 164.7, 158.9, 146.7, 108.7, 80.1, 78.0, 69.3, 66.8, 61.4, 52.4, 35.1, 32.8, 30.2, 30.1, 26.0, 23.7, 22.8, 14.4.

(2) The subject compound was also obtained by the method described below.

5-Acetamido-4-guanidino-9-O-octanoyl-2,3,4,5-tetradeoxy-7-O-methyl-D-glycero-D-galacto-non-2-enopyranosoic acid trifluoroacetic acid salt (3.0 g, 5.1 mmol) disclosed in Example 35 (ii) of U.S. Pat. No. 6,340,702 (Japanese Patent No. 3209946) was subjected to reversed phase column chromatography [Cosmosil 75C 18PREP (nacalai tesque), 100 g] and eluted with methanol/water (0/1-1/1-2/1). Fractions containing the compound of interest were vacuum concentrated. The precipitating crystals were suction filtered and vacuum dried. The resultant crystals were left in the air for one day to thereby yield the subject compound as a hydrate crystal (1.2 g; yield 49%). The property data of the resultant compound were consistent with those of the compound obtained in (1) above.

Preparation Example 2 5-Acetamido-4-guanidino-2,3,4,5-tetradeoxy-7-O-methyl-D-glycero-D-galacto-non-2-enopyranosoic acid

Figure US20100204314A1-20100812-C00006

5-Acetamido-4-guanidino-2,3,4,5-tetradeoxy-7-O-methyl-D-glycero-D-galacto-non-2-enopyranosoic acid trifluoroacetic acid salt (3.0 g, 5.1 mmol) disclosed in Example 28 (viii) of U.S. Pat. No. 6,340,702 (Japanese Patent No. 3209946) was purified in an ion-exchange resin column [Dowex-50X; (i) water and (ii) 5% aqueous ammonium solution] and further purified by reversed phase column chromatography [Cosmosil 75C 18PREP (nacalai tesque); water]. Fractions containing the compound of interest were vacuum concentrated. The resultant solid was washed with methanol, filtered and dried to thereby yield the subject compound (1.43 g) as a colorless solid.

1H Nuclear Magnetic Resonance Spectrum (400 MHz, CD3OD) δ ppm: 5.64 (1H, d, J=2.0 Hz), 4.43 (2H, m), 4.22 (1H, dd, J=10.0 Hz, 10.0 Hz), 4.00 (1H, m), 3.85 (1H, dd, J=10.0 Hz, 2.4 Hz), 3.68 (1H, dd, J=10.0 Hz, 5.5 Hz), 3.58 (1H, m), 3.43 (3H, s).

………………………….

WO 2013089168

Figure JPOXMLDOC01-appb-C000008

Figure JPOXMLDOC01-appb-C000009

…………………………..

US8455659

Process W is known as a method for manufacturing a compound represented by the formula (Ia), which is embraced in a compound represented by the formula (I) or a pharmacologically acceptable salt thereof, (hereinafter also referred to as “compound (Ia)”; the same shall be applied with respect to other (Patent Document 1). In Process W, n-Hep represents a 1-heptyl group.

Figure US08455659-20130604-C00004
Figure US08455659-20130604-C00005

Process X is known as a method for manufacturing compound (Ib), which is embraced in compound (I) or a pharmacologically acceptable salt thereof (Patent Document 2). Compound (IVk) is a synthetic intermediate in Process W. In Process X, n-Hep represents a 1-heptyl group.

Figure US08455659-20130604-C00006

Process Y is known as a method for manufacturing compound (IIIa), which is a trifluoroacetic acid salt of compound (III) (Non-patent Document 1). The procedures from compound (IVc) to compound (IVe) and from compound (IVf) to compound (IVh) in Process Y are the same as in Process W.

Figure US08455659-20130604-C00007
Figure US08455659-20130604-C00008

Process Z is known as a method for manufacturing compound (IIIa), which is a trifluoroacetic acid salt of compound (III) (Non-patent Document 2). In Process Z, the procedure from compound (IVf) to compound (IVh) is the same as in Process W, and the procedure from compound (IVh) to compound (IIIa) is the same as in Process Y.

Figure US08455659-20130604-C00009
Figure US08455659-20130604-C00010

From the viewpoint of industrial production, the aforementioned Process W, Process Y, or Process Z could be improved in points such as the following:

Want to know everything on vir series

click

http://drugsynthesisint.blogspot.in/p/vir-series-hep-c-virus-22.html

AND

http://medcheminternational.blogspot.in/p/vir-series-hep-c-virus.html

update…………


:ACIE 10.1002/anie.201408138

Scheme zanamivir and Lanimiwei is based on N- acetylneuraminic acid as a starting material, the price is more expensive (ca.13000RMB / kg). Ma recently from Shanghai Institute of Organic Chemistry greatly researcher on ACIE published zanamivir, Lanimiwei and CS-8958 is more simple synthetic route. References: ACIE 10.1002 / anie.201408138

LEDIPASVIR , 来迪派韦 , Ледипасвир , ليديباسفير


 

 1256388-51-8.png
File:Ledipasvir.svg
 
LEDIPASVIR, GS 5885
 CAS 1256388-51-8, PHASE 3
Methyl N-[(2S)-1-[(6S)-6-[5-[9,9-Difluoro-7-[2-[(1S,2S,4R)-3-[(2S)-2-(methoxycarbonylamino)-3-methylbutanoyl]-3-azabicyclo[2.2.1]heptan-2-yl]-3H-benzimidazol-5-yl]fluoren-2-yl]-1H-imidazol-2-yl]-5-azaspiro[2.4]heptan-5-yl]-3-methyl-1-oxobutan-2-yl]carbamate
C49H54F2N8O6, 889.0
also
Ledipasvir Acetone

Carbamic acid, N-((1S)-1-(((6S)-6-(5-(9,9-difluoro-7-(2-((1R,3S,4S)-2-((2S)-2-((methoxycarbonyl)amino)-3-methyl-1-oxobutyl)-2-azabicyclo(2.2.1)hept-3-yl)-1H-benzimidazol-6-yl)-9H-fluoren-2-yl)-1H-imidazol-2-yl)-5-azaspiro(2.4)hept-5-yl)carbonyl)-2-me

1441674-54-9
Chemical Formula:C52H60F2N8O7
Molecular Weight:947.08
2D chemical structure of 1441674-54-9
GS-5885 had been in phase III clinical development at Gilead for the oral treatment of chronic genotype 1 hepatitis C virus (HCV) infection, however no recent developments have been reported on this research.
 
NMR LEDIPASVIR FROM NET
DMSOD6
 
str1
 Chronic Hepatitis C virus (HCV) infection is a global health problem with an estimated 170 million individuals infected worldwide. HCV infection is a major European public health challenge, with a prevalence of 0.4-3.5% in different EU member states. It is the most common single cause of liver transplantation in the Union. HCV is divided into six major genotypes and numerous subtypes, which are based on phylogenetic relationship. Genotype 1 is the most common genotype in Europe, comprising approximately 70 % of infections. Genotype 3 is second most common, followed by genotype 2. Genotype 4 is predominant in Egypt, the nation in the world with the highest documented HCV prevalence. Genotypes 5 and -6 are uncommon in Europe and the US, but are more common in South Africa and South-East Asia, respectively (Simmonds et al, Hepatology 2005). HCV genotype does not clearly impact the rate of disease progression. Treatment response, or the required drug pressure (number of drugs, treatment duration) needed to obtain maximal activity with presently approved regimens, differs between genotypes. The goal of antiviral therapy against HCV is to reach sustained virological response (SVR), which has traditionally been defined as the absence of quantifiable virus in plasma at least 24 weeks after the end of therapy (SVR24). However, most relapses occur within 4 weeks of treatment discontinuation, and a 98-99% concordance has been shown between absence of quantifiable virus 12 weeks after therapy, and SVR24 (Florian et al, AASLD 2011). Therefore the absence of measurable virus 12 weeks post end of treatment (SVR12) is presently considered accepted by European and US regulators as the primary endpoint in clinical trials. Though occasional late relapses occur, in general the durability of SVR has been demonstrated (e.g., Ng and Saab, Clin Gastroenterol Hepatol 2011). Of note, SVR4 (absence of quantifiable virus 4 weeks after treatment discontinuation) has an approximately 90% positive predictive value for SVR24 (Florian et al, AASLD 2011). Until the European Commission marketing authorisation of sofosbuvir in January 2014, all approved therapeutic regimens for the treatment of chronic HCV infection contained an interferon. For the treatment of genotype 1 infection, the addition of either one of the NS3/4A protease inhibitors telaprevir or boceprevir, authorised in 2011, was considered standard of care. For genotypes other than GT-1, there were no direct-acting antivirals (DAA) authorised, therefore dual therapy with pegIFN/RBV was the standard of care. Interferon-based therapies have limited efficacy in many patients and are associated with potentially serious side effects that are important in limiting real life effectiveness. These include a risk of hepatic decompensation and septicaemia in patients with advanced liver disease, as well as bone marrow suppression. Also, there are psychiatric side effects such as depression, which considerably limits eligibility to treatment in the target population (e.g., Bini et al, Am J Gastroenterol 2005). For these reasons, the development of highly effective interferon-free regimens for the treatment of hepatitis C targets addresses an important previously unmet medical need. SOF/LDV is a fixed-dose combination (FDC) tablet containing sofosbuvir (a previously approved NS5B polymerase inhibitor) and ledipasvir, a new NS5A-inhibitor. HCV NS5A is a multifunctional protein with key functions in HCV replication, virus assembly, and the modulation of cellular signaling pathways (e.g., Sheel and Rice, Nature Medicine, 2013). The FDC tablet contains 400 mg of SOF and 90 mg of LDV. SOF/LDV has the potential to be a simple and effective all-oral, once-daily treatment regimen for chronic HCV infection
REF
The chemical name of ledipasvir acetone solvate (LDV-AS) is methyl [(2S)-1-{(6S)-6-[5-(9,9-difluoro-7-{2-[(1R,3S,4S)-2-{(2S)-2-[(methoxycarbonyl)amino]-3-methylbut anoyl}-2-azabicyclo[2.2.1]hept-3-yl]-1H-benzimidazol-6-yl}-9H-fluoren-2-yl)-1H-imidazol-2-yl]-5-aza spiro[2.4]hept-5-yl}-3-methyl-1-oxobutan-2-yl]carbamate propan-2-one (1:1), also known as carbamic acid, N-[(1S)-1-[[(6S)-6-[5-[9,9-difluoro-7-[2-[(1R,3S,4S)-2-[(2S)-2-[(methoxycarbonyl)amino]-3-methyl- 1-oxobutyl]-2-azabicyclo[2.2.1]hept-3-yl]-1H-benzimidazol-6-yl]-9H-fluoren-2-yl]-1H-imidazol-2-yl]-5 -azaspiro[2.4]hept-5-yl]carbonyl]-2-methylpropyl]-, methyl ester, compd. with 2-propanone (1:1) or methyl {(1S)-1-[(1R,3S,4S)-3-{5-[9,9-difluoro-7-(2-{(6S)-5-[N- (methoxycarbonyl)- l-valyl]-5-azaspiro[2.4]hept-6-yl}-1Himidazol-4-yl)-9H-fluoren-2-yl]-1H-benzimidazol-2-yl}-2-azabicyc lo[2.2.1]heptane-2-carbonyl]-2-ethylpropyl}carbamate, compound with 2-propanone (1:1) and it has the following structure:

str1

The structure of ledipasvir was unambiguously confirmed by 1 H, 13C and 19F NMR spectroscopy, UV spectroscopy, IR spectroscopy, high resolution mass spectrometry, elemental analysis and X-ray crystallography. LDV-AS is a white to tinted (off-white, tan, yellow, orange, or pink), slightly hygroscopic crystalline solid. It shows pH dependent solubility in aqueous media: it is slightly soluble in pH 2.3 buffer but practically insoluble in pH 4-7.5 buffers. It is freely soluble in ethanol and DMSO and slightly soluble in acetone. Ledipasvir is chiral and possesses 6 stereogenic centres and enantiomeric purity is controlled in starting material specifications. Three crystalline forms are known and ledipasvir acetone solvate is the designated commercial form. The first step for finished product manufacture involves the dissolution of ledipasvir in ethanol followed by spray-drying and thus precise control of morphology and particle size is not considered important. Ledipasvir is a chemical substance not previously authorised as a medicinal product in the European Union. Furthermore, it is not a salt, complex, derivative or isomer, (nor mixture of isomers), of a previously authorised substance. Whilst it contains some structural features in common with daclastavir, it is metabolically stable and the applicant presented data indicating that there are no common active metabolites. Therefore, the therapeutic moieties are not the same. Ledipasvir thus meets the definition of a New Active Substance according to the Notice to Applicants (NtA), Vol 2A, Chapter 1, Annex 3.

The mode of action of ledipasvir has not been directly established but indirect evidence is consistent with the compound targeting the NS5A molecule. In vitro resistance selection and cross-resistance studies, and the lack of HCV enzyme or kinase inhibition was taken to support the conclusion that ledipasvir targets NS5A as its mode of action. Ledipasvir has shown antiviral activity against HCV genotypes 1a and 1b with mean EC50 values of 0.031 and 0.004 nM, respectively. Antiviral activity determined as EC50 against genotypes 2 to 6 ranged from 0.15 to 530 nM. Ledipasvir showed no relevant antiviral activity at the highest concentration tested, or the highest concentration without cytotoxicity, against other virus such as bovine viral diarrhea virus (BVDV), RSV, HBV, HIV-1, HRV, influenza A and B, and a panel of flaviviruses (including West Nile virus, yellow fever virus, dengue virus, and banzai virus). Cytotoxicity of ledipasvir was characterised by CC50 of 4029 to >50000 nM using different cell lines (1b-Rluc-2, Huh-luc, 1a-HRlucp, Hep G2, SL3, Huh7, Hep-2, AD-38 and MT4 cells). Ledipasvir at 10 µM showed significant binding to 3 ion channels and 1 receptor in a radioligand binding assay screen against a panel of 68 mammalian ion channels and receptors. The IC50s of ledipasvir were 0.210 and 3.47 μM against sodium channel site 2 and calcium channel L-type (dihydropyridine), respectively. A 50% inhibition of androgen receptor was noted at 10 μM. Ledipasvir activity against 442 kinases was assessed using a quantitative polymerase chain reaction (qPCR)-based competition assay. Results showed weak competition for binding of 2 kinases, Bruton’s tyrosine kinase (BTK) and homeodomain-interacting protein kinase 1 (HIPK1) at 0.1 and 1 μM, respectively. Taking into account the high protein binding, >99.5%, of ledipasvir the large margin between unbound maximum clinical plasma levels (0.8 nM) and potential ion channel/receptor inhibition indicates limited clinical relevance.

Ledipasvir (formerly GS-5885) is a drug for the treatment of hepatitis C that was developed by Gilead Sciences.[1] After completingPhase III clinical trials, on February 10, 2014 Gilead filed for U.S. approval of a ledipasvir/sofosbuvirfixed-dose combination tablet for genotype 1 hepatitis C.[2][3] The ledipasvir/sofosbuvir combination is a direct-acting antiviral agent that interferes with HCV replication and can be used to treat patients with genotypes 1a or 1b without PEG-interferon or ribavirin.

Ledipasvir is an inhibitor of the hepatitis C virusNS5A protein.

Data presented at the 20th Conference on Retroviruses and Opportunistic Infections in March 2013 showed that a triple regimen of the nucleotide analog inhibitor sofosbuvir, ledipasvir, and ribavirin produced a 12-week post-treatment sustained virological response (SVR12) rate of 100% for both treatment-naive patients and prior non-responders with HCV genotype 1.[4][5] The sofosbuvir/ledipasvir coformulation is being tested with and without ribavirin. In February 2014 Gilead has filed for United StatesFood and Drug Administration (FDA) approval of ledipasvir/sofosbuvir oral treatment, without interferon and ribavirin.[6]

On October 10, 2014 the FDA approved the combination product ledipasvir 90 mg/sofosbuvir 400 mg called Harvoni.[7]

 Similar to sofosbuvir, the cost of Harvoni has been a controversial topic. It costs $1,125 per pill in the US, translating to $63,000 for an 8-week treatment course, $94,500 for a 12-week treatment course, or $189,000 for a 24-week treatment course. Gilead justifies the cost by outweighing the benefit of curing hepatitis C over the cost of spending double on liver transplants or temporarily treating liver diseases. Gilead has provided a ledipasvir/sofosbuvir assistance program for eligible underserved or underinsured hepatitis C patients who cannot afford the costs of treatment. [10]
 Hepatitis C is recognized as a chronic viral disease of the liver which is characterized by liver disease. Although drugs targeting the liver are in wide use and have shown
effectiveness, toxicity and other side effects have limited their usefulness. Inhibitors of hepatitis C virus (HCV) are useful to limit the establishment and progression of infection by HCV as well as in diagnostic assays for HCV.
The compound (l-{3-[6-(9,9-dif uoro-7-{2-[5-(2-methoxycarbonylamino-3-methyl- butyryl)-5-aza-spiro[2.4]hept-6-yl]-3H-imidazol-4-yl}-9H-fluoren-2-yl)-lH-benzoimidazol-2- yl]-2-aza-bicyclo[2.2.1]heptane-2-carbonyl}-2-methyl-propyl)-carbamic acid methyl ester, also known as ledipasvir, designated herein as Compound I, is known to be an effective anti-HCV agent, as described for example in WO 2010/132601. A synthesis of compound I is disclosed in U.S. Patent No. 8,088,368
Figure imgf000011_0001
Figure imgf000068_0001
acetone solvate . 1H NMR (400 MHz, DMSO-^, δ): 12.29 (s, 0.1H), 12.19 (d, J=4.0 Hz, 1H), 12.14 (s, 0.2H), 11.85 (s, 1H), 8.10 (s, 0.1H), 8.08 (s, 1H), 8.01 (s, 0.1H), 7.963 (m, 1H), 7.955 (s, 1H), 7.89 (d, J=6.4 Hz, 1H), 7.87 (s, 1H), 7.83 (dd, J=8.4, 2.4 Hz, 1H), 7.79 (dd, J=7.2, 2.8 Hz, 1H), 7.78-7.90 (misc., 0.9H), 7.70 (s, 1H), 7.61 (d, J=8.4 Hz, 1H), 7.55 (s, 1H), 7.51 (dd, J=8.8, 1.6 Hz, 1H), 7.44 (m, 0.1H), 7.31 (d, J=8.4 Hz, 1H), 7.21 (d, J=8.4 Hz, 1H), 6.91 (d, J=8.0 Hz, 0.2H), 6.77 (m, 0.2H), 5.34 (d, J=7.6 Hz, 0.1H), 5.20 (dd, J=8.0, 5.2 Hz, 1H), 5.18 (m, 0.1H), 4.88 (s, 0.1H), 4.67 (d, J=6.4 Hz, 1H), 4.55 (s, 1H), 4.17 (dd, J=8.0, 8.0 Hz, 1H), 4.10 (m, 0.2H), 4.01 (dd, J=8.4, 8.0 Hz, 1H), 3.97 (m, 0.1H), 3.82 (d, J=9.6 Hz, 1H), 3.77 (s, 0.2H), 3.71 (d, J=9.6 Hz, 1H), 3.554 (s, 3H), 3.548 (s, 3H), 3.43 (s, 0.4H), 3.20 (d, J=7.6 Hz, 0.3H), 2.77 (s, 0.1H), 2.66 (s, 1H), 2.41 (d, J=8.8 Hz, 1H), 2.22 (dd, J=12.4, 8.0 Hz, 1H), 2.13 (m, 0.4H), 2.08 (s, 6H), 2.05 (dd, J=13.2, 5.2 Hz, 1H), 1.99 (m, 2H), 1.92 (m, 1H), 1.77 (m, 2H), 1.61 (m, 0.3H), 1.56 (m, 1H), 1.46 (d, J=9.2 Hz, 1H), 1.33 (d, J=10.0 Hz, 0.1H), 0.97 (dd, J=6.4, 2.0 Hz, 3H), 0.93 (d, J=6.8 Hz, 3H), 0.88 (d, J=6.4 Hz, 3H), 0.87 (d, J=6.4 Hz, 3H), 0.80-1.05 (misc., 2H), 0.70 (m, 1H), 0.59 (m, 2H), 0.54 (m, 1H), 0.33 (m, 0.1H). HRMS-ESI+: [M + H]+ calcd for C49H5506N8F2, 889.4207; found, 889.4205.
 CLIP
 INTERMEDIATES
PATENT

Figure imgf000050_0001

 

PATENT

https://www.google.co.in/patents/US8088368
Example ED Preparation of Intermediate 5-Aza-spiro[2.4]heptane-5,6-dicarboxylic acid 5-benzyl ester 6-methyl ester
Figure US08088368-20120103-C00822

4-Methylene-pyrrolidine-1,2-dicarboxylic acid 1-benzyl ester 2-methyl ester

4-Methylene-pyrrolidine-1,2-dicarboxylic acid 1-tert-butyl ester (10.0 g, 44 mmol) was dissolved in MeOH (75 mL) at room temperature and HCl (4M in dioxane, 75 mL) was added. Stirring at room temperature was continued for 4 hours. All volatiles were removed in vacuo and a beige solid was obtained.
The crude material was suspended in DCM (100 mL) and N-Methyl morpholine (13.3 g, 132 mmol) was added. The mixture was cooled to 0° C. and benzyl chloroformate (8.26 g, 48.4 mmol) was added while stirring. After 30 minutes, the reaction was warmed to room temperature and the solution was washed with water and aqueous HCl (1M). The solution was dried over sodium sulfate. Filtration and evaporation of solvents gave crude product, which was purified by silica gel chromatography (eluent: EtOAc/hexanes) to yield the product (10.2 g). LCMS-ESI+: calc’d for C15H17NO4: 275.3 (M+). Found: 276.4 (M+H+).
5-aza-spiro[2.4]heptanes-5,6-dicarboxylic acid benzyl ester: An oven-dried 3-neck round bottom flask was equipped with a nitrogen inlet adaptor and a 250 mL addition funnel. The third neck was sealed with a septum. The flask was charged with a stir bar, dichlorormethane (120 mL) and diethyl zinc (1.0 M in hexane, 118 mL, 118 mmol) then cooled to 0° C. in an ice bath. The addition funnel was charged with dichloromethane (40 mL) and trifluoroacetic acid (9.1 mL, 118 mmol). After the diethyl zinc solution had cooled to 0° C. (about 25 minutes), the trifluoroacetic acid solution was added dropwise over 20 minutes to the stirred reaction mixture. After stirring for another 20 minutes at 0° C., diiodomethane (9.5 mL, 118 mmol) was added slowly over 4 minutes. After another 20 minutes, 4-methylene-pyrrolidine-1,2-dicarboxylic acid 1-benzyl ester 2-methyl ester (8.10 g, 29.4 mmol) was added in 30 mL dichloromethane by cannula. The flask containing 4-methylene-pyrrolidine-1,2-dicarboxylic acid 1-benzyl ester 2-methyl ester was then rinsed with another 10 mL dichloromethane and this solution was also transferred to the reaction mixture by cannula. The reaction mixture was allowed to warm to RT and stirred for 110 hours (about 5 days) after which the reagents were quenched with saturated aqueous ammonium chloride (˜150 mL). The contents of the flask were slowly poured into a 2 L sep funnel containing saturated aqueous sodium bicarbonate (˜800 mL). The aqueous phase was extracted three times with 300 mL ethyl acetate. The combined organics were dried over magnesium sulfate and concentrated to provide the crude material. The crude material was dissolved in 3:1:1 THF/water/acetone (165 mL) then treated with N-methylmorpholine-N-oxide (3.45 g, 29.4 mmol) and osmium tetroxide (4 wt % in water, 5 mL, 0.818 mmol). After stirring at RT for 7 h, the reagents were quenched with 1 M aqueous sodium thiosulfate (˜100 mL). The contents of the flask were then poured into a 1 L sep funnel containing water (˜300 mL). The aqueous phase was extracted three times with 300 mL dichloromethane. The combined organics were dried over magnesium sulfate and concentrated. The crude residue was purified by silica column chromatography (5% to 45% EtOAc/hexane) to provide 5-aza-spiro[2.4]heptane-5,6-dicarboxylic acid 5-benzyl ester 6-methyl ester as a clear oil (5.54 g, 19.15 mmol, 65%) as a clear oil. 1H NMR (CDCl3) δ 7.36-7.29 (m, 5H), 5.21-5.04 (m, 2H), 4.56-4.47 (m, 1H), 3.75 (s, 1.5H), 3.60 (m, 1.5H), 03.51-3.37 (m, 2H), 2.32-2.25 (m, 1H), 1.87-1.80 (m, 1H), 0.64-0.51 (m, 4H).

5-Aza-spiro[2.4]heptane-5,6-dicarboxylic acid 5-benzyl ester

5-Aza-spiro[2.4]heptane-5,6-dicarboxylic acid 5-benzyl ester 6-methyl ester (244 mg, 0.840 mmol) was dissolved in THF (2.0 mL)/MeOH (1.5 mL) An aqueous solution of LiOH (35.5 mg, 0.84 mmol) was added and stirring at room temperature was continued. After 3 hours, the reaction was neutralized with aqueous HCl (1M) and the organic solvents were removed in vacuo. The crude mixture was diluted with water and EtOAc and the organic layer was collected. All volatiles were removed in vacuo and the crude acid was used without further purification. LCMS-ESI+: calc’d for C15H17NO4: 275.3 (M+). Found: 276.3 (M+H+).

Example ED′

Figure US08088368-20120103-C00823
Figure US08088368-20120103-C00824

2,7-Dibromo-9,9-difluoro-9H-fluorene

2,7-Dibromo-fluoren-9-one (4.0 g, 11.8 mmol) was suspended in deoxofluor (12 mL) at room temperature and EtOH (4 drops) was added. The stirred suspension was heated at T=90° C. for 24 hours (CAUTION: Use of deoxofluor at elevated temperatures, as described above, is strongly discouraged as rapid and violent exotherms may occur). The reaction was cooled to room temperature and poured onto ice containing sodium bicarbonate. A solid formed and was collected via filtration. The crude material was taken into EtOAc and was washed with aqueous HCl (1M) and brine. The solution was dried over sodium sulfate. Filtration and evaporation of solvents gave crude product, which was purified by silica gel chromatography (eluent: EtOAc/hexanes) to yield the product 2,7-Dibromo-9,9-difluoro-9H-fluorene (3.2 g). 19F-NMR: 282 MHz, (dmso-d6) δ: −111.6 ppm.
Before using the material in the next step, it was exposed as a solution in EtOAc to charcoal.

5-Aza-spiro[2.4]heptane-5,6-dicarboxylic acid 5-benzyl ester 6-[2-(7-bromo-9,9-difluoro-9H-fluoren-2-yl)-2-oxo-ethyl]ester

2,7-Dibromo-9,9-difluoro-9H-fluorene (372 mg, 1.04 mmol), Pd(PPh3)(30.0 mg, 0.026 mmol), PdCl2(PPh3)(18.2 mg, 0.026 mmol), As(PPh3)(5.0 mg) were dissolved in dioxane (10 mL) under an argon atmosphere. Ethoxyvinyl-tributyl tin (376.4 mg, 1.04 mmol) was added. The mixture was heated for 140 minutes at 85° C. (oil bath). The reaction was cooled to room temperature. N-bromo succinimide (177 mg, 1.0 mmol) was added followed by water (2 mL). The reaction was stirred at room temperature for 3 hours, after which the majority of the dioxane was removed in vacuo. The crude reaction mixture was diluted with EtOAc and was washed with water. All volatiles were removed in vacuo. Toluene was added and all volatiles were removed in vacuo for a second time. The crude material was dissolved in DMF/MeCN (2 mL, 1:1) at room temperature. A solution of N-Cbz-4-cyclopropyl (L) Proline (0.84 mmol) and DIEA (268 mg, 2.08 mmol) in MeCN (2 mL) was added and stirring at room temperature was continued. After 14 hours, most of the MeCN was removed in vacuo and the crude reaction mixture was diluted with EtOAc. The mixture was washed with aqueous HCl (1M), aqueous LiCl solution (5%), brine, and was dried over sodium sulfate. Filtration and evaporation of solvents gave the crude reaction product, which was purified via silica gel chromatography (eluent: EtOAc/hexanes) to yield the product 5-Aza-spiro[2.4]heptane-5,6-dicarboxylic acid 5-benzyl ester 6-[2-(7-bromo-9,9-difluoro-9H-fluoren-2-yl)-2-oxo-ethyl]ester (176 mg). LCMS-ESI+: calc’d for C30H24BrF2NO5: 596.4 (M+). Found: 595.2/597.2 (M+H+).

6-[5-(7-Bromo-9,9-difluoro-9H-fluoren-2-yl)-1H-imidazol-2-yl]-5-aza-spiro[2.4]heptane-5-carboxylic acid benzyl ester

5-Aza-spiro[2.4]heptane-5,6-dicarboxylic acid 5-benzyl ester 6-[2-(7-bromo-9,9-difluoro-9H-fluoren-2-yl)-2-oxo-ethyl]ester (172 mg, 0.293 mmol) was dissolved in m-xylenes (6.0 mL). Ammonium acetate (226 mg, 2.93 mmol) was added and the reaction was stirred at 140° C. for 60 minutes under microwave conditions. The reaction was cooled to room temperature and all volatiles were removed in vacuo. The crude material was purified via silica gel chromatography (eluent: EtOAc/hexanes) to yield the product 6-[5-(7-Bromo-9,9-difluoro-9H-fluoren-2-yl)-1H-imidazol-2-yl]-5-aza-spiro[2.4]heptane-5-carboxylic acid benzyl ester (80.3 mg). LCMS-ESL’: calc’d for C30H24BrF2N3O2: 576.4 (M+). Found: 575.2/577.2 (M+H+).

(1-{6-[5-(7-Bromo-9,9-difluoro-9H-fluoren-2-yl)-1H-imidazol-2-yl]-5-aza-spiro[2.4]heptane-5-carbonyl}-2-methyl-propyl)-carbamic acid methyl ester

6-[5-(7-Bromo-9,9-difluoro-9H-fluoren-2-yl)-1H-imidazol-2-yl]-5-aza-spiro[2.4]heptane-5-carboxylic acid benzyl ester (800 mg, 1.38 mmol) was dissolved in DCM (15 mL) and HBr in AcOH (37%, 2 mL) was added and stirring at room temperature was continued. After 180 minutes, the suspension was diluted with hexanes and the solid was collected via filtration and was washed with hexanes and subjected to vacuum. The crude material was used in the next step without further purification. The crude material was dissolved in DMF (4.0 mL) and DIEA (356 mg, 2.76 mmol) was added. A solution of 2-(L)-Methoxycarbonylamino-3-methyl-butyric acid (242 mg, 1.38 mmol), HATU (524 mg, 1.38 mmol) and DIEA (178 mg, 1.38 mmol) in DMF (1 mL) was added. The reaction was stirred at room temperature. After 50 minutes, the reaction was diluted with EtOAc and was washed with aqueous bicarbonate solution, aqueous LiCl solution (5%), brine, and was dried over sodium sulfate. Filtration and removal of solvents in vacuo gave the crude material, which was purified by silica gel chromatography (eluent: EtOAc/hexanes) to yield the slightly impure product (1-{6-[5-(7-Bromo-9,9-difluoro-9H-fluoren-2-yl)-1H-imidazol-2-yl]-5-aza-spiro[2.4]heptane-5-carbonyl}-2-methyl-propyl)-carbamic acid methyl ester (878 mg). LCMS-ESI+: calc’d for C29H29BrF2N4O3: 599.5 (M+); Found: 598.5/600.5 (M+H+).

3-[6-(9,9-Difluoro-7-{2-[5-(2-methoxycarbonylamino-3-methyl-butyryl)-5-aza-spiro[2.4]hept-6-yl]-3H-imidazol-4-yl}-9H-fluoren-2-yl)-1H-benzoimidazol-2-yl]-2-aza-bicyclo[2.2.1]heptane-2-carboxylic acid tert-butyl ester

(1-{6-[5-(7-Bromo-9,9-difluoro-9H-fluoren-2-yl)-1H-imidazol-2-yl]-5-aza-spiro[2.4]heptane-5-carbonyl}-2-methyl-propyl)-carbamic acid methyl ester (840 mg, 1.4 mmol), 3-[6-(4,4,5,5-Tetramethyl-[1,3,2]dioxaborolan-2-yl)-1H-benzoimidazol-2-yl]-2-aza-bicyclo[2.2.1]heptane-2-carboxylic acid tert-butyl ester (615 mg, 1.4 mmol), Pd(PPh3)(161 mg, 0.14 mmol), K2CO(579 mg, 4.2 mmol), were dissolved in DME (15 mL)/water (3 mL) under an argon atmosphere. The mixture was heated for 120 minutes at 85-90° C. (oil bath). After 120 minutes additional boronate ester (61 mg, 0.14 mmol) was added and heating was continued. After 3 hours, the reaction was cooled to room temperature. Most of the DME was removed in vacuo and the crude reaction mixture was diluted with EtOAc. The mixture was washed with brine and was dried over sodium sulfate. Filtration and evaporation of solvents gave the crude reaction product, which was purified via silica gel chromatography (eluent: EtOAc/hexanes) to yield the product 3-[6-(9,9-Difluoro-7-{2-[5-(2-methoxycarbonylamino-3-methyl-butyryl)-5-aza-spiro[2.4]hept-6-yl]-3H-imidazol-4-yl}-9H-fluoren-2-yl)-1H-benzoimidazol-2-yl]-2-aza-bicyclo[2.2.1]heptane-2-carboxylic acid tert-butyl ester (878 mg). LCMS-ESI+: calc’d for C47H51F2N7O5: 831.9 (M+). Found: 832.7 (M+H+).

(1-{3-[6-(9,9-Difluoro-7-{2-[5-(2-methoxycarbonylamino-3-methyl-butyryl)-5-aza-spiro[2.4]hept-6-yl]-3H-imidazol-4-yl}-9H-fluoren-2-yl)-1H-benzoimidazol-2-yl]-2-aza-bicyclo[2.2.1]heptane-2-carbonyl}-2-methyl-propyl)-carbamic acid methyl ester

3-[6-(9,9-Difluoro-7-{2-[5-(2-methoxycarbonylamino-3-methyl-butyryl)-5-aza-spiro[2.4]hept-6-yl]-3H-imidazol-4-yl}-9H-fluoren-2-yl)-1H-benzoimidazol-2-yl]-2-aza-bicyclo[2.2.1]heptane-2-carboxylic acid tert-butyl ester (115 mg, 0.138 mmol) was dissolved in DCM (2 mL) and HCl in dioxane (4M, 2 mL) was added and stirring at room temperature was continued. After 20 minutes, all volatiles were removed in vacuo. The crude material was used in the next step without further purification. The crude material was dissolved in DMF (1.5 mL) and DIEA (53.4 mg, 0.414 mmol) was added. A solution of 2-(L) Methoxycarbonylamino-3-methyl-butyric acid (24.2 mg, 0.138 mmol), HATU (52.4 mg, 0.138 mmol) and DIEA (17.8 mg, 0.138 mmol) in DMF (1 mL) was added. The reaction was stirred at room temperature. After 20 minutes, the reaction was diluted with EtOAc and was washed with aqueous bicarbonate solution, aqueous LiCl solution (5%), brine, and was dried over sodium sulfate. Filtration and removal of solvents in vacuo gave the crude material, which was purified by RP-HPLC (eluent: water/MeCN w/0.1% TFA) to yield the product (1-{3-[6-(9,9-Difluoro-7-{2-[5-(2-methoxycarbonylamino-3-methyl-butyryl)-5-aza-spiro[2.4]hept-6-yl]-3H-imidazol-4-yl}-9H-fluoren-2-yl)-1H-benzoimidazol-2-yl]-2-aza-bicyclo[2.2.1]heptane-2-carbonyl}-2-methyl-propyl)-carbamic acid methyl ester (76 mg). LCMS-ESI+: calc’d for C49H54F2N8O6: 888.9 (M+). Found: 890.0 (M+H+).
1H-NMR: 300 MHz, (dmso-d6) δ: 8.20-7.99 (m, 8H), 7.73 (s, 2H), 7.37-7.27 (m, 2H), 5.25 (dd, J=7.2 Hz, 1H), 4.78 (s, 1H) 4.54 (s, 1H), 4.16 (m, 1H), 4.02 (m, 1H), 3.87 (m, 1H), 3.74 (m, 1H), 3.55 (s, 3H), 3.53 (s, 3H), 2.75 (m, 1H), 2.25 (m, 2H), 2.09-2.04 (m, 2H), 1.88-1.79 (m, 2H), 1.54 (m, 1H), 0.94-0.77 (m, 15H) 0.63 (m, 4H) ppm. 19F-NMR: 282 MHz, (dmso-d6) δ: −109.1 ppm [−74.8 ppm TFA]

https://www.google.co.in/patents/US8088368

Figure US08088368-20120103-C00802

2-(5-{9,9-Difluoro-7-[2-(2-Boc-2-aza-bicyclo[2.2.1]hept-3-yl)-3H-benzoimidazol-5-yl]-9H-fluoren-2-yl}-1H-imidazol-2-yl)-pyrrolidine-1-carboxylic acid tert-butyl ester: A mixture of 2-[5-(7-Bromo-9,9-difluoro-9H-fluoren-2-yl)-1H-imidazol-2-yl]-pyrrolidine-1-carboxylic acid tert-butyl ester (324 mg, 0.627 mmol), 3-[6-(4,4,5,5-Tetramethyl-[1,3,2]dioxaborolan-2-yl)-1H-benzoimidazol-2-yl]-2-aza-bicyclo[2.2.1]heptane-2-carboxylic acid tert-butyl ester (1.1 eq., 304 mg), [1,1′ bis(diphenylphosphino)ferrocene]dichloropalladium(II)(3%, 15 mg), tetrakis(triphenylphosphine)palladium (3%, 22 mg) and potassium carbonate (3.3 eq., 285 mg) in 10 mL DME and 3 mL water was heated to 90° C. under Argon for 3 hours. The reaction mixture was cooled and diluted with ethyl acetate and washed with saturated sodium bicarbonate solution. The organic layer was dried (MgSO4), concentrated and purified by flash column chromatography (silica gel, 20 to 100% ethyl acetate/hexane) to give 2-(5-{9,9-Difluoro-7-[2-(2-Boc-2-aza-bicyclo[2.2.1]hept-3-yl)-3H-benzoimidazol-5-yl]-9H-fluoren-2-yl}-1H-imidazol-2-yl)-pyrrolidine-1-carboxylic acid tert-butyl ester (361 mg, yield 77%). LCMS-ESI: calc’d for C43H46F2N6O4: 748.86. Found: 749.2 (M+H+).

(1-{2-[5-(9,9-Difluoro-7-{2-[2-(2-methoxycarbonylamino-3-methyl-butyryl)-2-aza-bicyclo[2.2.1]hept-3-yl]-3H-benzoimidazol-5-yl}-9H-fluoren-2-yl)-1H-imidazol-2-yl]-pyrrolidine-1-carbonyl}-2-methyl-propyl)-carbamic acid methyl ester (Example DK): 4N HCl in dioxane (2 mL) was added to 2-(5-{9,9-Difluoro-7-[2-(2-Boc-2-aza-bicyclo[2.2.1]hept-3-yl)-3H-benzoimidazol-5-yl]-9H-fluoren-2-yl}-1H-imidazol-2-yl)-pyrrolidine-1-carboxylic acid tert-butyl ester (361 mg, 0.482 mmol) and the reaction mixture was stirred at room temperature for 4 hours. The reaction mixture was concentrated and dried overnight under vacuum. The residue was dissolved in DMF (5 mL) and to this solution was added 2-Methoxycarbonylamino-3-methyl-butyric acid (2 eq., 169 mg), diisopropyl ethylamine (6 eq., 0.5 mL), followed by HATU (2 eq., 367 mg). Reaction mixture was stirred at 0° C. for 30 minutes. The reaction mixture was dissolved in ethyl acetate and washed with saturated sodium bicarbonate solution. The organic layer was dried (MgSO4), concentrated and purified by flash column chromatography (silica gel, 0 to 20% MeOH/ethyl acetate), followed by preparative reverse phase HPLC (GEMINI, 5 to 100% ACN/H2O+0.1% TFA). Product was lyophilized to give (1-{2-[5-(9,9-Difluoro-7-{2-[2-(2-methoxycarbonylamino-3-methyl-butyryl)-2-aza-bicyclo [2.2.1]hept-3-yl]-3H-benzoimidazol-5-yl}-9H-fluoren-2-yl)-1H-imidazol-2-yl]-pyrrolidine-1-carbonyl}-2-methyl-propyl)-carbamic acid methyl ester (285 mg, 59%).
1H-NMR: 300 MHz, (CD3OD-d4) δ: 8.05-7.82 (m, 9H), 5.40-5.22 (m, 2H), 4.72 (m, 1H), 4.39 (d, 1H), 4.239d, 1H), 4.17 (m, 1H), 3.91 (m, 2H), 3.62 (d, 6H), 2.98 (m, 1H), 2.58 (m, 1H), 2.37-2.18 (m, 4H), 2.18-1.92 (m, 4H), 1.80 (m, 2H), 1.09-0.85 (m, 12H). 19F-NMR: 300 MHz, (CD3OD-d4) δ: −112.88. LCMS-ESI+: calc’d for C47H52F2N8O862.96. Found: 863.5 (M+H+).

 

PATENTS
SEE

WO 2010132601
WO 2013040492
WO 2013059630
WO 2013059638

CLIP

 

Ledipasvir (Harvoni) Ledipasvir is a potent NS5A inhibitor that is approved for use in combination with sofosbuvir, a nucleotide inhibitor of viral polymerase, for the treatment of chronic hepatitis C virus genotype 1 infection.14,130,131 This combination was discovered and developed at Gilead Sciences and is marketed as the fixed combination with brand name of Harvoni. The synthesis of ledipasvir has been reported in the literature132 and the routes shown in Schemes 22–24 below represent the most efficient and largest scale sequence reported in the patent literature.133,134 The synthesis of the spirocyclopropane proline intermediate 136 is described in Scheme 21. Bis-iodination of cyclopropane-1,1-diyldimethanol (131) in the presence of triphenylphosphine gave diiodide 132 in 70% yield. N-Boc-glycine ethyl ester (133) was then treated with sodium hydride followed by diiodide 132 to give the protected proline analog 134 in 61% yield. Saponification of the ester followed by a classical resolution with (1S,2R)-amino-indanol gave enantomerically pure salt 135. Liberation of the free acid with 1 M HCl followed by treatment with potassium tert-butoxide provided enantiopure potassium salt 136 in high yield. The synthesis of the difluoro-fluorene Suzuki coupling intermediate 143 is described in Scheme 22. Iodination of 2-bromofluorene (137) produced aryl iodide 138 in 95% yield, which was then treated with lithium hexamethyldisilazide and N-fluorobenzenesulfonimide (NFSI) to give the difluoro intermediate 139 in 82% yield. Formation of the Grignard reagent of 139 through reaction with isopropylmagnesium chloride followed by condensation with Weinreb amide 140 gave chloroketone 141 in 71% yield. The potassium salt of the cyclopropyl proline intermediate 136 (described in Scheme 21) was coupled with 141 to give keto ester 142 in high yield. Heating 142 with ammonium acetate resulted in formation of the imidazole ring in intermediate 143 in 77% yield. The completion of the synthesis of ledipasvir is described in Scheme 23. Commercially available (1R,3S,4S)-N-Boc-2-azabicyclo [2.2.1]heptane-3-carboxylic acid (144) was coupled to 4-bromo- 1,2-benzenediamine (145) using EDC/HOBt to give a mixture ofamides 146a/146b in 72% yield. Heating mixture 146a/146b with acetic acid affected cyclization to benzimidazole 147 in 94% yield. Palladium mediated coupling of bromide 147 to bis(pinacolato)diboron gave intermediate148 which was then coupled in the same reaction vessel to bromide 143 generated in Scheme 22. This was followed by formation of the oxalate salt to give the protected central core of ledipasvir (149) in good overall yield. Removal of the amine protecting groups gave diamine 150 which was coupled to two equivalents of Moc-valine (151) via EDC/HOBt to give ledipasvir XVII in 73% yield. 19. Lobeglitazone sulfate

130. Gentile, I.; Buonomo, A. R.; Borgia, F.; Castaldo, G.; Borgia, G. Expert Opin.Invest. Drugs 2014, 23, 561.
131. Smith, M. A.; Chan, J.; Mohammad, R. A. Ann. Pharmacother. 2015, 49, 343.132. Link, J. O.; Taylor, J. G.; Xu, L.; Mitchell, M.; Guo, H.; Liu, H.; Kato, D.;Kirschberg, T.; Sun, J.; Squires, N.; Parrish, J.; Keller, T.; Yang, Z. Y.; Yang, C.;Matles, M.; Wang, Y.; Wang, K.; Cheng, G.; Tian, Y.; Mogalian, E.; Mondou, E.;Cornpropst, M.; Perry, J.; Desai, M. C. J. Med. Chem. 2014, 57, 2033.
133. Guo, H.; Kato, D.; Kirschberg, T. A.; Liu, H.; Link, J. O.; Mitchell, M. L.; Parrish, J.P.; Squires, N.; Sun, J.; Taylor, J.; Bacon, E. M.; Canales, E.; Cho, A.; Cottell, J. J.;Desai, M. C.; Halcomb, R. L.; Krygowski, E. S.; Lazerwith, S. E.; Liu, Q.;Mackman, R.; Pyun, H. J.; Saugier, J. H.; Trenkle, J. D.; Tse, W. C.; Vivian, R. W.;Schroeder, S. D.; Watkins, W. J.; Xu, L.; Yang, Z. Y.; Kellar, T.; Sheng, X.; Clarke,M. O. N. H.; Chou, C. H.; Graupe, M.; Jin, H.; McFadden, R.; Mish, M. R.;Metobo, S. E.; Phillips, B. W.; Venkataramani, C. WO Patent 2010132601A1,2010.
134. Scott, R. W.; Vitale, J. P.; Matthews, K. S.; Teresk, M. G.; Formella, A.; Evans, J.W. US Patent 2013324740A1, 2013.
135. Jin, S. M.; Park, C. Y.; Cho, Y. M.; Ku, B. J.; Ahn, C. W.; Cha, B.-S.; Min, K. W.;Sung, Y. A.; Baik, S. H.; Lee, K. W.; Yoon, K.-H.; Lee, M.-K.; Park, S. W. Diab.Obes. Metab. 2015, 17, 599.
136. Lee, H. W.; Ahn, J. B.; Kang, S. K.; Ahn, S. K.; Ha, D.-C. Org. Process Res. Dev.2007, 11, 190.
137. Lee, H. W.; Kim, B. Y.; Ahn, J. B.; Kang, S. K.; Lee, J. H.; Shin, J. S.; Ahn, S. K.; Lee,S. J.; Yoon, S. S. Eur. J. Med. Chem. 2005,

PAPER

The Discovery of Ledipasvir (GS-5885), a Potent Once-Daily Oral NS5A Inhibitor for the Treatment of Hepatitis C Virus Infection

J. Med. Chem., Just Accepted Manuscript
DOI: 10.1021/jm401499g
Publication Date (Web): December 9, 2013

http://pubs.acs.org/doi/abs/10.1021/jm401499g?prevSearch=LEDIPASVIR&searchHistoryKey=

http://pubs.acs.org/doi/pdf/10.1021/jm401499g

1H-NMR: 300 MHz, (dmso-d6) δ: 8.20-7.99 (m, 8H), 7.73 (s, 2H), 7.37 – 7.27
(m, 2H), 5.25 (dd, J = 7.2 Hz, 1H), 4.78 (s, 1H) 4.54 (s, 1H), 4.16 (m, 1H), 4.02 (m,
1H), 3.87 (m,1H), 3.74 (m, 1H), 3.55 (s, 3H), 3.53 (s, 3H), 2.75 (m, 1H), 2.25 (m,
2H), 2.09 – 2.04 (m, 2H), 1.88 – 1.79 (m, 2H), 1.54 (m, 1H), 0.94 – 0.77 (m, 15H)
0.63 (m, 4H) ppm.

19F-NMR: 282 MHz, (dmso-d6) δ: -109.1 ppm [-74.8 ppm TFA].
HRMS (ESI-TOF) m/z: [M + H]+
calc’d for C49H55F2N8O6: 889.4207; Found: 889.4214.
methyl [(2S)-1-{(6S)-6-[5-(9,9-difluoro-7-{2-[(1R,3S,4S)-2-{(2S)-2-[(methoxycarbonyl)amino]-3-methylbutanoyl}-2-azabicyclo[2.2.1]hept-3-yl]-1H-benzimidazol-6-yl}-9H-fluoren-2-yl)-1H-imidazol-2-
yl]-5-azaspiro[2.4]hept-5-yl}-3-methyl-1-oxobutan-2-yl]carbamate (39 NOS IS LEDISPAVIR

 

PATENT

https://www.google.co.in/patents/WO2013184702A1?cl=en

Synthesis of 25

Figure imgf000047_0001

25

B. Synthesis of 26 and 27

Figure imgf000047_0002

25 26 27

[0186] To a flask was charged 25 (20.00 g, 0.083 mol), 4-bromo-l,2-benzenediamine (16.74 g, 0.089 mol, 1.08 equiv.), hydroxybenzotriazole (HOBt) (13.96 g, 0.091 mol, 1.1 equiv.), and l-ethyl-3-(3-dimethylaminopropyl) carbodiimide HC1 (EDC.HC1) (17.48 g, 0.091 mol, 1.1 equiv.). The flask was cooled in an ice bath, and was charged with N,N- dimethylacetamide (DMAc, 80 mL). The reaction was allowed to cool to ca. 10 °C with stirring. N-methylmorpholine (NMM) (27.34 mL, 0.249 mol, 3 equiv.) was added over 5 minutes keeping the internal temperature below 20 °C. The reaction was stirred at rt for 20 h. Upon reaction completion, the reaction mixture was added to MTBE (200 mL) and water (600 mL) in a separatory funnel and was gently shaken. The layers were allowed to separate, and the aqueous layer was removed. The aqueous layer was extracted twice with MTBE (50 mL), and the organic extracts were combined. The combined organic extracts were then extracted with water (500 mL), forming a mixture that did not separate well. The mixture was filtered over an appropriate solid support and the layers were separated. The organic phase was concentrated under vacuum, and the resulting residue was dissolved in diisopropyl ether (100 mL). The solution was cooled to ca. 5 °C with stirring. Acetic acid (5.22 mL, 0.091 mol, 1.1 equiv.) was added slowly keeping the internal temperature below 10 °C, and the resulting suspension was stirred 2 h at 5 °C. The thick suspension was then filtered, and the solid was rinsed with diisopropyl ether (100 mL), followed by heptane (100 mL). The cake was dried under vacuum to give the product as a light-beige solid as a mixture of regioisomers 26 and 27 (28.19 g, 72%, >99% AN). 1H NMR (400 MHz, DMSO) mixture of 26 & 27 (data is for the two rotamers of the major regioisomer): δ 9.25 (s, 0.5H), 9.13 (s, 0.5H), 7.08 (d, J= 8.3 Hz, 0.5H); 7.06 (d, J= 8.2 Hz, 0.5H), 6.92 (d, J= 2.2 Hz, 0.5H), 6.89 (d, J= 2.1 Hz, 0.5H), 6.71 (dd, J= 8.4, 2.2, 0.5H), 6.66 (dd, J= 8.4, 2.2, 0.5H), 5.10 (br s, 1H), 5.05 (br s, 1H), 4.15 (br s, 0.5H), 4.10 (br s, 0.5H), 3.76 (s, 1H), 2.64 (br s, 1H), 1.96- 1.88 (m, 1H), 1.77-1.67 (m, 1H), 1.67-1.19 (m, 4H), 1.41 (s, 4.5H), 1.33 (s, 4.5H). MS-ESI+: [M + H]+ calcd for Ci8H25Br03N3, 410.1, 412.1; found, 410.0, 412.0

[0187] The disclosure provides in some embodiments the use of other coupling reagents. These include but are not limited to N,N”-dicyclohexylcarbodiimide (DCC), NJV- diisopropylcarbodiimide (DIC), 6-chloro-2,4-dimethoxy-s-triazine (CDMT), O- benzotriazole-N^N^A^-tetramethyl-uronium-hexafluoro-phosphate (HBTU), and 2-(7-Aza- 1H- benzotriazole-l-yl)-l,l,3,3-tetramethyluronium hexafluorophosphate (HATU).

[0188] The amine base also can be varied or omitted completely. For instance the amine is selected from tertiary amines (R3N), 2,6-lutidine, pyridine, dicyclohexylmethylamme, and N- methylmorpholine (NMM).

[0189] Suitable solvent alternatives are selected from DMF, NMP, dialkyl and cyclic ethers R20, THF, 2-MeTHF, DCM, DCE, toluene, EtOAc, IP Ac, acetone, MIBK, and MEK.

[0190] Suitable temperatures for the reaction range from about -20 °C to 80 °C.

NMR PREDICT

1H/13C  NMR PREDICT

H EXPLODED

Ledipasvir 1H NMR VALUES Ledipasvir 1H NMRGRAPH Ledipasvir 13C NMRGRAPH Ledipasvir 13CNMR VALUES

 

COSY

COSY NMR prediction (22)

Links
1)Link, John O.et al; The Discovery of Ledipasvir (GS-5885), a Potent Once-Daily Oral NS5A Inhibitor for the Treatment of Hepatitis C Virus Infection; Journal of Medicinal Chemistry (2013), Ahead of Print.DOI:10.1021/jm401499g

2)Ray, Adrian S. et al; Preparation of pyridazinylmethylimidazopyridine derivatives and analogs for use in the treatment of hepatitis C virus using combination chemotherapy, PCT Int. Appl., WO2013040492

3) Delaney, William E. et al ; Preparation of pyridazinylmethylimidazopyridine derivatives and analogs for use in the treatment of hepatitis C virus using combination chemotherapy, PCT Int. Appl., wo2012087596

4) Delaney, William E., IV et al; Preparation of quinoline derivatives and analogs for use in the treatment of hepatitis C virus infection in combination with ribavirin; PCT Int. Appl., wo2011156757

5) Guo, Hongyan et al; Preparation of biaryls, arylheteroaryls, heteroaryls, biarylacetylenes and related compounds end-capped with amino acid or peptide derivatives as antiviral agents; PCT Int. Appl., WO2010132601

6)Phase III (Sofosbuvir + Ledipasvir) ION-1 study: (Clinical Trial number: NCT01701401):
Title:A Phase 3, Multicenter, Randomized, Open-Label Study to Investigate the Efficacy and Safety of Sofosbuvir/Ledipasvir Fixed-Dose Combination (FDC) +/- Ribavirin for 8 Weeks and Sofosbuvir/Ledipasvir Fixed-Dose Combination (FDC) for 12 Weeks in Treatment-Naive Subjects With Chronic Genotype 1 HCV Infection

7) Phase III (Sofosbuvir + Ledipasvir) ION-2 study: (Clinical Trial number: NCT01768286)
Title:A Phase 3, Multicenter, Randomized, Open-Label Study to Investigate the Efficacy and Safety of Sofosbuvir/GS-5885 Fixed-Dose Combination ± Ribavirin for 12 and 24 Weeks in Treatment-Experienced Subjects With Chronic Genotype 1 HCV Infection

8) Phase III (Sofosbuvir + Ledipasvir) ION-3 study: (Clinical trial number: NCT01851330)
Title:A Phase 3, Multicenter, Randomized, Open-Label Study to Investigate the Efficacy and Safety of Sofosbuvir/Ledipasvir Fixed-Dose Combination (FDC) +/- Ribavirin for 8 Weeks and Sofosbuvir/Ledipasvir Fixed-Dose Combination (FDC) for 12 Weeks in Treatment-Naive Subjects With Chronic Genotype 1 HCV Infection

References

  1. “Ledipasvir” (PDF). United States Adopted Name.
  2. “Ledipasvir-submitted-to-FDA”.
  3. “GS-5885”. Gilead Sciences.
  4. ELECTRON: 100% Suppression of Viral Load through 4 Weeks’ Post-treatment for Sofosbuvir + Ledipasvir (GS-5885) + Ribavirin for 12 Weeks in Treatment-naïve and -experienced Hepatitis C Virus GT 1 Patients. Gane, Edward et al. 20th Conference on Retroviruses and Opportunistic Infections. March 3–6, 2013. Abstract 41LB.
  5. CROI 2013: Sofosbuvir + Ledipasvir + Ribavirin Combo for HCV Produces 100% Sustained Response. Highleyman, Liz. HIVandHepatitis.com. 4 March 2013.
  6. “Gilead Files for U.S. Approval of Ledipasvir/Sofosbuvir Fixed-Dose Combination Tablet for Genotype 1 Hepatitis C”. Gilead Sciences. 10 February 2014.
  7. “U.S. Food and Drug Administration Approves Gilead’s Harvoni® (Ledipasvir/Sofosbuvir), the First Once-Daily Single Tablet Regimen for the Treatment of Genotype 1 Chronic Hepatitis C”. 10 October 2014. Retrieved 10 October 2014.
  8. Afdhal, N; Zeuzem, S; Kwo, P; Chojkier, M; Gitlin, N; Puoti, M; Romero-Gomez, M; Zarski, J. P.; Agarwal, K; Buggisch, P; Foster, G. R.; Bräu, N; Buti, M; Jacobson, I. M.; Subramanian, G. M.; Ding, X; Mo, H; Yang, J. C.; Pang, P. S.; Symonds, W. T.; McHutchison, J. G.; Muir, A. J.; Mangia, A; Marcellin, P; Ion-1, Investigators (2014). “Ledipasvir and sofosbuvir for untreated HCV genotype 1 infection”. New England Journal of Medicine 370 (20): 1889–98. doi:10.1056/NEJMoa1402454. PMID 24725239. edit
  9. http://www.gilead.com/~/media/Files/pdfs/medicines/liver-disease/harvoni/harvoni_pi.pdf
  10. http://www.hepatitisc.uw.edu/page/treatment/drugs/ledipasvir-sofosbuvir
Ledipasvir
Ledipasvir.svg
Systematic (IUPAC) name
Methyl N-[(2S)-1-[(6S)-6-[5-[9,9-Difluoro-7-[2-[(1S,2S,4R)-3-[(2S)-2-(methoxycarbonylamino)-3-methylbutanoyl]-3-azabicyclo[2.2.1]heptan-2-yl]-3H-benzimidazol-5-yl]fluoren-2-yl]-1H-imidazol-2-yl]-5-azaspiro[2.4]heptan-5-yl]-3-methyl-1-oxobutan-2-yl]carbamate
Clinical data
Legal status
Routes of
administration
Oral
Pharmacokinetic data
Bioavailability 76%
Protein binding >99%
Metabolism No cytochromemetabolism
Biological half-life 47 hrs
Identifiers
CAS Registry Number 1256388-51-8
ATC code None
ChemSpider 29271894
ChEBI CHEBI:85089 Yes
Chemical data
Formula C49H54F2N8O6
Molecular mass 889.00 g/mol

 

 

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THE VIEWS EXPRESSED ARE MY PERSONAL AND IN NO-WAY SUGGEST THE VIEWS OF THE PROFESSIONAL BODY OR THE COMPANY THAT I REPRESENT

////////////////GS-5885, LEDIPASVIR

Supporting Info

PATENT 1

Patent application WO2010132601A1 (primary patent) discloses the base compound of ledipasvir. The application claims a general structural formula (Markush) of new amide compounds useful for treating disorders associated with HCV. This patent, if granted, serves as a blocking patent preventing competitors from making the product. The claims are very broad, using a Markush structure of antiviral agents. As per the WIPO ISR, claims 1-19 are novel and inventive. However, according to the ISR, all remaining claims (claims 20 to 173), covering a large number of compounds, lack both novelty and inventive step, due to lack of support from the patent specification and in the light of prior art. Prosecution at the USPTO Three patents have been granted in the United States: US8088368B2, claiming the base compound by general structural formula; US8273341B2 (a division of US8088368B2), claiming a method of inhibiting HCV; and US8575118B2 (a continuation of US8273341B2 and a division of US8088368B2), claiming specific amide compounds not covered in the other two related patents. The examination report of US8088368B2 reveals that the application was allowed after the applicant cancelled and amended claims on Markush substuents. The examination report of US8273341B2 reveals that the application was allowed after the applicant amended a claim ‘A method of treating HCV’ to ‘A method of inhibiting HCV´. The examination report of US8575118B2 reveals that the application was allowed after the applicant cancelled claims already covered by the related patents, and limited claims to four specific compounds. Patent 1 has been filed in various jurisdictions:  The patent has been granted by the ARIPO, in South Africa, and the United States.  The patent (or a related patent) is pending in Argentina, Australia, Canada, China, as well as China, Hong Kong SAR, the EAPO, the EPO, Israel, India, Japan, New Zealand, Singapore, and Ukraine.  Legal status is not available for Colombia, Ecuador, Mexico, Peru, Uruguay, and Viet Nam. 13 Litigation / Opposition on Patent 1 In December 2013, Gilead Sciences filed apatent infringement lawsuit against Abbott Laboratories and AbbVie Inc., in the United States District Court for the District of Delaware (case Number: 1:13cv02034). The case involves Gilead Sciences patents US8088368B2, US8273341B2, and US8575118B2.

PATENT 2 Patent application WO2013184698A1 is a product and process patent, claiming new crystalline solvate forms of ledipasvir useful for treating a subject suffering from HCV infection. The application also claims processes of manufacture of such amorphous and crystalline forms with specific X-ray diffraction peaks, and compositions and combinations comprising them. The application has just recently been published and no written opinion on patentability is available at this stage. As per the available information (details available in the Annex):  The patent is pending at the EPO and the United States. There are no litigation or opposition procedures reported.

PATENT 3 Patent application WO2013184702A1 is a process patent, claiming processes for the preparation of ledipasvir. The disclosure also provides compounds that are synthetic intermediates to compounds of ledipasvir. The claims are moderately narrow covering crystalline and amorphous forms of ledipasvir with specific X-ray diffraction peaks. The application has just recently been published and no written opinion on patentability is available at this stage. As per the available information (details available in the Annex):  The patent is pending at the EPO and the United States. There are no litigation or opposition procedures reported.

PATENT 4 Patent application WO2012087596A1 is a formulation patent, claiming various formulations comprising a combination of ledipasvir with GS-9256, or tegobuvir or with other compounds. The application also claims methods of treatment with the said combinations for reducing viral load in a person infected with HCV. 14 As per the WIPO ISR, the application is novel but not inventive in comparison to the closest prior art retrieved during the search. The combinations claimed in the instant application are not disclosed in the prior art, thus the combinations are novel. However, the prior art discloses various combinations, therefore, the problem to be solved through the invention should be new combinations with fewer side effects. Further, no experimental data of synergism has been provided to support double, triple, or quadruple combinations. Thus, according to the ISR, the instant invention cannot be regarded as inventive. As per the available information (details available in the Annex):  The patent has been granted in Argentina.  The patent is pending in Australia, Canada, the EPO, and the United States.  Legal status is not available for Japan and Uruguay. There are no litigation or opposition procedures reported.

PATENT 5 Patent application WO2013040492A2 is a formulation and method of use patent, claiming compositions and a method of using the combination for the treatment of HCV. Drug combinations are used, and the compositions include sofosbuvir, PSI-7851 and ledipasvir. Since the application claims a group of compounds of Markush structure, it gives the claims a broad scope. As per the WIPO ISR the application is novel but lacks the inventive step in light of prior art. The invention lacks an inventive step as it would be obvious to a person skilled in the art to combine the diastereoisomer of the present invention, disclosed in the prior art, with other antiviral agents to provide an alternative HCV therapy. As per the available information (details available in the Annex):  The patent is pending in Australia, Canada, the EPO, and the United States. There are no litigation or opposition procedures reported. This patent is listed in the sofosbuvir report as Patent No. 7

http://www.who.int/phi/implementation/ip_trade/ledipasvir_report_2014-09-02.pdf

str1

str2

str3

str4

str5

SUMMARY The search revealed patents filed with respect to ledipasvir by the Sponsor as well as a nonSponsor. The ledipasvir Sponsor patent collection comprises 5 different patents (patent families) with 47 family members published in 23 jurisdictions. The majority of these patent applications are still pending in the respective patent offices (see Patents 1 to 5 in the Annex). Patent 1 is the primary patent, claiming the base compound through a Markush claim, along with various substituents. Where granted, this patent can prevent competitors from making ledipasvir. Patents 2 and 3 claim processes to make ledipasvir and thus if granted will require competitors to design around these patents and use other production processes. The chemical product itself is not protected. Patents 4 and 5 claim combinations of different HCV drugs with ledipasvir, and their formulations. There is competition in the field by AbbVie, Inc., which filed formulation patents. Note: The search also revealed two patents that are relevant for all seven reports. Patent applications WO2013059630A1 and WO2013059638A1 inter alia claim the use of combinations of unnamed direct-acting antiviral agents for treating HCV, where the treatment does not include administration of interferon or ribavirin, and the treatment lasts between 8-12 weeks. The description and the dataset for these two patents can be found in the Working Paper on ombitasvir (Patents No 3 and 4). These patents are in litigation. Detailed information can be found in the Working Paper on sofosbuvir under Patent No 2.

World Drug Tracker: LEDIPASVIR

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LEDIPASVIR

Biological Activity of Ledipasvir

Ledipasvir(GS5885) is an inhibitor of the hepatitis C virus  NS5A protein.  Ledipasvir is an experimental drug for the treatment of hepatitis C.
IC50 Value: 141 nM (EC50, JFH1/3a-NS5A hybrid replicon) [1]
Target: HCV NS5A
in vitro:  Against JFH1/3a-NS5A, DCV was more potent (EC(50) = 0.52 nM) than GS-5885 (EC(50) = 141 nM). DCV sensitivity was increased against JFH1/3a-NS5A-M28V (EC50 = 0.006 nM), A30V (EC(50) = 0.012 nM), and E92A (EC(50) = 0.004 nM) while the NS5A-A30K and -Y93H variants exhibited reduced sensitivity to DCV (EC50 values of 23 nM and 1120 nM, respectively) and to GS-5885 (EC50 values of 1770 nM and 4300 nM, respectively) [1].
in vivo: GS-5885 was well tolerated and resulted in median maximal reductions in HCV RNA ranging from 2.3 log(10) IU/ml (1 mg QD) to 3.3 log(10) IU/ml (10 mg QD in genotype 1b and 30 mg QD). E(max) modeling indicated GS-5885 30 mg was associated with>95% of maximal antiviral response to HCV genotype 1a. HCV RNA reductions were generally more sustained among patients with genotype 1b vs. 1a. Three of 60 patients had a reduced response and harbored NS5A-resistant virus at baseline. NS5A sequencing identified residues 30 and 31 in genotype 1a, and 93 in genotype 1b as the predominant sites of mutation following GS-5885 dosing. Plasma pharmacokinetics was consistent with QD dosing [2].
Toxicity:
Clinical trial: Combination Therapy for Chronic Hepatitis C Infection. Phase 2

Clinical Information of Ledipasvir

Product Name Sponsor Only Condition Start Date End Date Phase Last Change Date
Ledipasvir Gilead Sciences Inc Hepatitis C virus infection 31-OCT-12 31-DEC-14 Phase 3 12-SEP-13
Gilead Sciences Inc Hepatitis C virus infection 31-OCT-13 31-JAN-15 Phase 3b 11-NOV-13
Gilead Sciences Inc Hepatitis C virus infection 31-MAY-13 31-DEC-14 Phase 3 12-SEP-13
Gilead Sciences Inc Hepatitis C virus infection 31-DEC-10 30-APR-14 Phase 2b 28-AUG-13
Gilead Sciences Inc Hepatitis C virus infection 31-JUL-11 30-JUN-13 Phase 2 22-AUG-13
Gilead Sciences Inc Hepatitis C virus infection 31-JUL-11 30-APR-13 Phase 2b 03-OCT-12
Gilead Sciences Inc Hepatitis C virus infection 31-OCT-13 31-JAN-15 Phase 3 11-NOV-13
Gilead Sciences Inc Hepatitis C virus infection 31-MAY-13 31-DEC-14 Phase 3 12-SEP-13
Gilead Sciences Inc Hepatitis C virus infection 31-OCT-12 31-DEC-14 Phase 3 12-SEP-13
Gilead Sciences Inc Hepatitis C virus infection 31-JUL-11 30-APR-13 Phase 2 03-OCT-12
Gilead Sciences Inc Hepatitis C virus infection 31-JUL-11 30-JUN-13 Phase 2b 22-AUG-13

update………..

Image result for SHANGHAI FOREFRONT PHARMACEUTICAL CO., LTD

Ledipasvir.svg

WO 2016145990, Ledipasvir, New patent, SHANGHAI FOREFRONT PHARMACEUTICAL CO., LTD

(WO2016145990) METHOD OF PREPARATION FOR LEDIPASVIR AND DERIVATIVE THEREOF, AND INTERMEDIATE COMPOUND FOR PREPARATION OF LEDIPASVIR

SHANGHAI FOREFRONT PHARMCEUTICAL CO., LTD [CN/CN]; Room 1306, No.781 Cailun Road China (Shanghai) Pilot Free Trade Zone, Pudong New Area Shanghai 201203 (CN)

HUANG, Chengjun; (CN).
FU, Gang; (CN).
FU, Shaojun; (CN).
WEI, Zhewen; (CN).
LI, Wei; (CN).
ZHANG, Xixuan; (CN)

chinese machine translation please bear………..

Leidipawei (Ledipasvir, LDV, the structure as shown in Formula 1-LDV) was developed by Gilead hepatitis C drugs, FDA has granted LDV / SOF (Sofosbuvir) fixed dose combination drug therapy breakthrough finds that this combination therapy is expected in the short 8-week period to cure patients with genotype 1HCV, but without injections of interferon or ribavirin (ribavirin).
US20100310512 Leidipawei reported synthetic route is as follows:
2 side chain compound 1-LDV are Moc-Val, but in the compound 21 in the first to introduce Cbz-, then introduced into the left Moc-Val 13-Br in the compound by hydrolysis and condensation, and the right side chains prior to 17 -Br Boc-introduced, and then condensed by the introduction of the right hydrolyzed Moc-Val, i.e., it is not required to introducing a protecting group, then 2 times by hydrolysis, condensation of 2 times the target product. Cumbersome reaction steps, and the product raw material is expensive, tedious synthetic methods to make the product more expensive raw material costs, requires the use of more efficient ways to reduce material costs.
US2013324740 reported Leidipawei the following preparation method:
Law methodology US20100310512 efficiency in high, but still prepared Boc protected compound 24, compound 27, as well as through hydrolysis to remove the protecting group Boc, the yield is still not high, but also increase the waste emissions.
Thus, there remains the need to find simpler, more efficient Leidipawei preparation.
Route 1
Law Compound 11 first introduced in Moc-val group, Boc protection is not required, can significantly improve the synthesis efficiency and reduce waste emissions.
Route 2
Law Compound 11, Compound 3-Moc were first introduced Moc-Val, got rid of all the protection, deprotection, significantly reduced synthetic steps to improve the synthesis efficiency, production cycle reduced significantly, waste emissions significantly lower raw material costs significantly reduction, with significant industrial significance.
Route 3
Law of the compound 4-Br-Moc-Boc, the compound 5-Moc-Boc protecting group is introduced, it can reduce the effects of electron-rich N atoms of catalyst, dramatically reducing the amount of catalyst and promote the reaction, an increase of raw materials utilization. Since the catalyst and raw materials expensive, so this route can significantly reduce raw material costs. Meanwhile, the product line also reduces the defluorination impurities content.
Synthesis of Compound 1-LDV: Example 32
In three bottle was charged with compound 1′-LDV-Bz-Bz (5.25g, 4.5mmol), potassium phosphate aqueous solution (1M / L, 50mL) and tert-amyl alcohol (50 mL), warmed to 90 deg.] C, stirred for 5 hours, cooled to room temperature, ethyl acetate (100 mL). The organic phase was dried over anhydrous sodium sulfate, and concentrated to give the product (4G, yield 100%).

 

SMILES COC(=O)N[C@@H](C(C)C)C(=O)N1CC2(CC2)C[C@H]1c3ncc([nH]3)c4ccc5c6ccc(cc6C(F)(F)c5c4)c7ccc8nc([nH]c8c7)[C@@H]9[C@H]%10CC[C@H](C%10)N9C(=O)[C@@H](NC(=O)OC)C(C)C

World Drug Tracker


World Drug Tracker

DARUNAVIR


DARUNAVIR

206361-99-1  CAS NO

[(1S,2R)-3-[[(4-Aminophenyl)sulfonyl] (2-methylpropyl)amino]-2-hydroxy-1-(phenylmethyl)propyl]carbamic acid (3R,3aS,6aR)-hexahydrofuro[2,3-b]furan-3-yl ester

M. P.:- 72-74 °C (dec)

MW: 547.66

Darunavir and processes for its preparation are disclosed in EP0715618, W09967417, EP1725566 and Bioorganic & Medicinal Chemistry Letters (2004), 14(4), 959-963.

J Med Chem. 2013 May 23;56(10):4017-27. doi: 10.1021/jm400231v

US20050250845 discloses various pseudopolymorphs of darunavir and processes for their preparation. According to this application, “pseudopolymorph” is defined as a crystalline form of a compound in which solvent molecules are incorporated in the lattice structure. The Form B disclosed in the patent application is a pseudopolymorph wherein water is used as solvent. The thermogravimetric experiments of the Form B shows weight loss of 3.4% in the temperature range 25-78°C (water), 5.1% in the temperature range 25-1 10°C (ethanol and water) and further 1.1% weight loss (ethanol) in temperature range 110-200° C. Further at the drying step the Form B showed about 5.6% weight loss. The obtained dried product was hygroscopic and it adsorbed up to 6.8% water at high relative humidity. Amorphous form of darunavir is disclosed in US20050250845 and the publication in J.Org. Chem. 2004, 69, 7822 – 7829.

US 7700645 patent disclosed amorphous Darunavir, various solvates of Darunavir including ethanolate and method for their preparation as well as their use as a medicament. Journal of Organic Chemistry 2004, 69, 7822-7829 disclosed amorphous Darunavir is obtained by purification with column chromatography in 2% methanol in chloroform as eluent. PCT publication WO2010086844A1 disclosed crystalline dimethylsulfoxide solvate and crystalline tetrahydrofuran solvate of darunavir. The publication also disclosed the amorphous darunavir having the IR spectrum with characteristic peaks at about 1454 and 1365 cm“1

PCT publication WO201 1083287A2 disclosed crystalline darunavir hydrate substantially free of any non aqueous solvent.

Drug information:- Darunavir is an Anti-microbial drug further classified as anti-viral agent of the class protease inhibitor. It is used either single or in combination with other drugs for the treatment of human immunodeficiency virus.

Darunavir (brand name Prezista, formerly known as TMC114) is a drug used to treat HIV infection. It is in the protease inhibitor class. Prezista is an OARAC recommended treatment option for treatment-naïve and treatment-experienced adults and adolescents.Developed by pharmaceutical company Tibotec, darunavir is named after Arun K. Ghosh, the chemist who discovered the molecule at the University of Illinois at Chicago. It was approved by the Food and Drug Administration (FDA) on June 23, 2006.[2]

Darunavir is a second-generation protease inhibitor (PIs), designed specifically to overcome problems with the older agents in this class, such as indinavir. Early PIs often have severe side effects and drug toxicities, require a high therapeutic dose, are costly to manufacture, and show a disturbing susceptibility to drug resistant mutations. Such mutations can develop in as little as a year of use, and effectively render the drugs useless.

Darunavir was designed to form robust interactions with the protease enzyme from many strains of HIV, including strains from treatment-experienced patients with multiple resistance mutations to PIs.

Darunavir received much attention at the time of its release, as it represents an important treatment option for patients with drug-resistant HIV. Patient advocacy groups pressured developer Tibotec not to follow the previous trend of releasing new drugs at prices higher than existing drugs in the same class. Darunavir was priced to match other common PIs already in use, such as the fixed-dose combination drug lopinavir/ritonavir.

PREZISTA (darunavir) is an inhibitor of the human immunodeficiency virus (HIV-1) protease.

PREZISTA (darunavir), in the form of darunavir ethanolate, has the following chemical name: [(1S,2R)-3-[[(4-aminophenyl)sulfonyl](2-methylpropyl)amino]-2-hydroxy-1-(phenylmethyl)propyl]-carbamic acid (3R,3aS,6aR)-hexahydrofuro[2,3-b]furan-3-yl ester monoethanolate. Its molecular formula is C27H37N3O7S • C2H5OH and its molecular weight is 593.73. Darunavir ethanolate has the following structural formula:

PREZISTA (darunavir) Structural Formula Illustration

Darunavir ethanolate is a white to off-white powder with a solubility of approximately 0.15 mg/mL in water at 20°C.

Patent
Country
Patent Number
Approved
Expires (estimated)
United States 7700645 2006-12-26 2026-12-26
United States 6335460 1992-08-25 2012-08-25
Canada 2469343 2008-05-13 2022-12-12
Canada 2224738 2002-08-27 2016-06-28
4-11-2012
METHODS FOR THE PREPARATION OF HEXAHYDROFURO[2,3-b]FURAN-3-OL
12-28-2011
Substituted Aminophenylsulfonamide Compounds as Hiv Protease Inhibitor
12-23-2011
POLYMORPHS OF DARUNAVIR
12-14-2011
METHODS FOR THE PREPARATION OF N-ISOBUTYL-N-(2-HYDROXY-3-AMINO-4-PHENYLBUTYL)-P-NITROBENZENESULFONYLAMIDE DERIVATIVES
11-30-2011
Protease inhibitor precursor synthesis
6-31-2011
PROCESS FOR THE PREPARATION OF (3R,3AS,6AR)-HEXAHYDROFURO [2,3-B] FURAN-3-YL (1S,2R)-3-[[(4-AMINOPHENYL) SULFONYL] (ISOBUTYL) AMINO]-1-BENZYL-2-HYDROXYPROPYLCARBAMATE
9-29-2010
Aminophenylsulfonamide Derivatives as Hiv Protease Inhibitor
8-11-2010
Process for the preparation of (3R,3aS,6aR)-hexahydrofuro [2,3-b] furan-3-yl (1S,2R)-3[[(4-aminophenyl) sulfonyl] (isobutyl) amino]-1-benzyl-2-hydroxypropylcarbamate
7-30-2010
RELATING TO ANTI-HIV TABLET FORMULATIONS
7-30-2010
COMBINATION FORMULATIONS
7-2-2010
METHODS AND INTERMEDIATES USEFUL IN THE SYNTHESIS OF HEXAHYDROFURO [2,3-B]FURAN-3-OL
5-7-2010
METHODS AND COMPOSITIONS FOR TREATING HIV INFECTIONS
4-21-2010
Pseudopolymorphic forms of a hiv protease inhibitor
9-21-2007
Immunoassays, Haptens, Immunogens and Antibodies for Anti-HIV Therapeutics
6-23-2006
Method for treating HIV infection through co-administration of tipranavir and darunavir
6-3-2005
Combination of cytochome p450 dependent protease inhibitors
Cited Patent Filing date Publication date Applicant Title
WO2010086844A1 Dec 8, 2009 Aug 5, 2010 Mapi Pharma Hk Limited Polymorphs of darunavir
WO2011048604A2 * Sep 16, 2010 Apr 28, 2011 Matrix Laboratories Limited An improved process for the preparation of darunavir
WO2011083287A2 Oct 6, 2010 Jul 14, 2011 Cipla Limited Darunavir polymorph and process for preparation thereof
CN102584844A * Jan 11, 2011 Jul 18, 2012 浙江九洲药业股份有限公司 Darunavir crystal form and method for preparing same
US6248775 Apr 8, 1999 Jun 19, 2001 G. D. Searle & Co. α- and β-amino acid hydroxyethylamino sulfonamides useful as retroviral protease inhibitors
US7700645 May 16, 2003 Apr 20, 2010 Tibotec Pharmaceuticals Ltd. Pseudopolymorphic forms of a HIV protease inhibitor
Reference
1 JOURNAL OF ORGANIC CHEMISTRY vol. 69, 2004, pages 7822 – 7829
2 * VAN GYSEGHEM E ET AL: “Solid state characterization of the anti-HIV drug TMC114: Interconversion of amorphous TMC114, TMC114 ethanolate and hydrate“, EUROPEAN JOURNAL OF PHARMACEUTICAL SCIENCES, ELSEVIER, AMSTERDAM, NL, vol. 38, no. 5, 8 December 2009 (2009-12-08), pages 489-497, XP026764329, ISSN: 0928-0987, DOI: 10.1016/J.EJPS.2009.09.013 [retrieved on 2009-09-24]

Virus-encoded proteases, which are essential for viral replication, are required for the processing of viral protein precursors. Interference with the processing of protein precursors inhibits the formation of infectious virions. Accordingly, inhibitors of viral proteases may be used to prevent or treat chronic and acute viral infections. Darunavir has HIV protease inhibitory activity and is particularly well suited for inhibiting HIV-I and HIV -2 viruses. Darunavir, chemically (1 S^R.S’R.S’aS.e’aRJ-fS’he ahydrofuro^.S-b ]furanyl-[3-( 4-aminobenzenesulfonyl)isobutylamino [- 1-benzyl-zhydroxypropyl]carbamate. Darunavir is represented by the following structure:

Darunavir and its pharmaceutically acceptable salts were disclosed in US 6248775 patent, wherein Darunavir is prepared by condensing 2R-hydroxy-3-[[(4-aminophenyl)sulfonyl](2- methylpropyl)amino]-1S(phenylmethyl)propylamine with hexahydro-furo[2,3-b]furan-3-ol in anhydrous acetonitrile in the presence of anhydrous pyridine and Ν,Ν’-disuccinimidyl carbonate at ambient temperature.

US 7700645 patent disclosed amorphous Darunavir, various solvates of Darunavir including ethanolate and method for their preparation as well as their use as a medicament. Journal of Organic Chemistry 2004, 69, 7822-7829 disclosed amorphous Darunavir is obtained by purification with column chromatography in 2% methanol in chloroform as eluent. PCT publication WO2010086844A1 disclosed crystalline dimethylsulfoxide solvate and crystalline tetrahydrofuran solvate of darunavir. The publication also disclosed the amorphous darunavir having the IR spectrum with characteristic peaks at about 1454 and 1365 cm“1

PCT publication WO201 1083287A2 disclosed crystalline darunavir hydrate substantially free of any non aqueous solvent.

Darunavir Ethanolate, has the chemical name: [(1 S, 2R)-3-[[(4-aminophenyl) sulfonyl](2- methylpropyl)amino]-2-hydroxy-1-(phenylmethyl)propyl]carbamic acid (3/?, 3aS, 6a/?)- hexahydrofuro[2,3-i>]furan-3-yl ester monoethanolate and has the following structural formula:

Darunavir and its process are first disclosed in US 6248775, wherein 2 ?-hydroxy-3-[[(4- aminophenyl)sulfonyl](2-methylpropyl)amino]-1 S(phenylmethyl) propylamine (4) is reacted with (3R, 3aS, 6aR)-hexahydrofuro[2,3- >]furan-3-ol in anhydrous acetonitrile in the presence of N, W-disuccinimidyl carbonate, anhydrous pyridine at ambient temperature followed by workup to get Darunavir (Scheme A).

Scheme A

Darunavir

US 20050250845 disclosed the various solvates of Darunavir including ethanolate and method for their preparation as well as their use as a medicament. The same application disclosed the amorphous Darunavir by Raman spectra without process details.

WO 2005063770 discloses process for the preparation of Darunavir ethanolate, wherein 2R-hydroxy-3-[[(4-aminophenyl)sulfonyl](2-methylpropyl)amino]-1 S-(phenylmethyl)propyl amine (4) is reacted with (3R, 3aS, 6a ?)-hexahydrofuro[2,3-b]furan-3-ol in the presence of N, /V-disuccinimidyl carbonate, triethylamine, 41% methylamine in ethanol in a mixture of ethyl acetate and acetonitrile followed by workup and crystallization from ethanol to get Darunavir ethanolate (Scheme B).

Scheme B

In the prior art process, compound of formula 4 condensed with (3/?, 3aS, 6aR)- hexahydrofuro[2,3-6]furan-3-ol in large excess of solvent or solvent mixture containing large excess of base or mixture of bases to get Darunavir. Further, the obtained products by the processes described in the prior art are not satisfactory, from purity point of view. We have repeated the Darunavir synthetic procedures as described in the prior art and found that relatively large amounts of impurities were obtained along with Darunavir (Table-1) which need repeated crystallizations in different solvents to get desired quality of the final product resulting in poor yields. Among other impurities, the carbonic acid [(1/?,2S)-1-{((4-amino-benzenesulfonyl)-isobutyl-amino)-methyl}-2-((3R,3aSI6aR)- hexahydro-furot2,3-/3]furan-3-yloxycarbonylamino)-3-phenyl-propylester (3R,3aS,6aR)- hexahydro-furo[2,3-ft]furan-3-yl ester (difuranyl impurity of formula 1) is identified.

Conditions:-

i. Phenyl magnesium bromide, Cuprous cyanide, tetrahydrofuran, 23 °C, 1 h,

ii. t-Butyl hydroperoxide, titanium tetraisopropoxide, diethyl D-tartrate, dichloromethane, -22 °C, 24 h,

iii. Azidotrimethylsilane, titanium tetraisopropoxide, Benzene, reflux, 25 min,

iv. 2-Acetoxyisobutyryl chloride, Chloroform, 23 °C, 8 h,

v. Isobutyl amine, isopropanol, 80 °C, 12 h,

vi 4-aminobenzenesulfonyl chloride, aq. Sodium bicarbonate, dichloromethane, 23 °C, 12 h,

vii. 10% palladium on carbon, hydrogen gas (50 psi), methanol, acetic acid, tetrahydrofuran, room temperature, 2 h,

viii. [3R, 3aS,6aS]-3-hydroxyhexahydrofuro[2,3-b]-furan, disuccanamidyl carbonate, triethylamine, acetonitrile, 23 °C, 12 h

Schematic Representation for Synthesis of Darunavir

Preparation of Darunavir is described in US patent 05,158,713, and also in WO9967417 and WO9967254. Accordingly, 2-vinyloxirane 1 on reacting with phenyl magnesium bromide in presence of tetrahydrofuran solvent and cuprous cyanide catalyst give 4-phenylbut-2-ene-1-ol 2. Oxidizing 2 with t-Butyl hydroperoxide in presence of titanium tetraisopropoxide and diethyl D-tartrate using dichloromethane as solvent give [(3S)-3-benzyloxiran-2-yl]methanol 3.

Heating 3 with azidotrimethylsilane in presence of titanium tetraisopropoxide using benzene as solvent give (2S,3S)-3-azido-4-phenyl-butane-1,2-diol 4. The 1,2-dipl compound 4 underwent cyclization when treated with 2-acetoxyisobutyryl chloride in chloroform give (2S)-2-[(1S)-1-azido-2-phenyl-ethyl]oxirane 5, which was further heating with isobutylamine and isopropanol at higher temperature give (2R,3S)-3-azido-1-(isobutylamino)-4-phenyl-butan-2-ol 6. Compound 6 was reacted with 4-aminobenzenesulfonyl chloride in presence of aq. Sodium bicarbonate as base and dichloromethane as solvent resulting in to 4-amino-N-[(2R,3S)-3-azido-2-hydroxy-4-phenyl-butyl]-N-isobutyl-benzenesulfonamide 7.

Hydrogenating 7 with 10% palladium on carbon catalyst using hydrogen gas (50 psi) in methanol and tetrahydrofuran solvent in presence of small amount of acetic acid at ambient temperature resulted in to 4-amino-N-[(2R,3S)-3-amino-2-hydroxy-4-phenyl-butyl]-N-isobutyl-benzenesulfonamide 8. The final step involves reacting 8 with [3R,3aS,6aS]-3-hydroxyhexahydrofuro[2,3-b]-furan and disuccanamidyl carbonate in presence of triethylamine base and acetonitrile as solvent afford [(1S,2R)-3-[[(4-Aminophenyl)sulfonyl] (2-methylpropyl)amino]-2-hydroxy-1-(phenylmethyl)propyl]carbamic acid (3R,3aS,6aR)-hexahydrofuro[2,3-b]furan-3-yl ester also called Darunavir 9.

…………………………

http://www.google.com/patents/WO2013114382A1?cl=en

process for the preparation of amorphous Darunavir is as

Process for the preparation of intermediate 2 is as shown in below scheme.

Examples

Example -1 : Preparation of [(1S, 2S)-3-chloro-2-hydroxy-1-(phenyl methyl) propyl] carbamic acid tert-butyl ester (5).

The solution of (3S)-3-(tert-butoxycarbonyl) amino-1-chloro-4-phenyl-2-butanone (Chloromethyl ketone 6,100 g) and aluminium isopropoxide (35 g) in isoprpylalcohol was heated to mild reflux and maintained for 3 hours. After completion of reaction distilled off isopropyl alcohol up to 50 % under vacuum and the resultant mass was cooled to 25-35°C. Water was added to the distillate, pH was adjusted to 3.0-4.0 with acetic acid and maintained the stirring for 2 hours at 25-35°C. The obtained solid was filtered and washed with water. The wet cake was taken into isopropyl alcohol (400mL) and heated to reflux for 60minutes, the mass was cooled to 25-35°C again maintain the stirring for 60minutes, the obtained solid was filtered and washed with isopropyl alcohol. The wet product was dried under normal drying to get title compound 5 (yield 80 g). Example -2: Preparation of [(1 S, 2R)-3-[(2-methylpropyl) amino]-2-hydroxy-1- (phenylmethyl) propyl] carbamic acid tert-butyl ester (4).

The mixture of [(1S, 2S)-3-chloro-2-hydroxy-1-(phenylmethyl) propyl] carbamic acid tert-butyl ester (5,100 g), isobutyl amine (294 g), sodium carbonate (31.3 g) and water was heated to 60 – 65°C and maintained for 3hours. After completion of reaction water (200 mL) was added and distilled out excess isobutyl amine under vacuum at below 75°C. Water (800 mL) was added to the distillate, cooled to 25-35°C and stirred for 2 hours. The obtained solid was filtered and washed with water to get title compound 4 (yield 105 g).

Example -3: Preparation of [(1S, 2R)-3-[[(4-nitrophenyl) sulfonyl] (2-methylpropyl) amino]- 2-hydroxy-1-(phenylmethyl) propyl] carbmic acid tert-butylester (3).

[(1 S, 2R)-3-[(2-methylpropyl) amino]-2-hydroxy-1 -(phenyl methyl) propyl] carbamic acid tert-butyl ester (4, 100 gm) and triethylamine (39.04 g) was added to methylenedichloride (1200 mL) and the temperature was raised to 40°C. p-nitro benzene sulfonyl chloride solution (72.3g of p-NBSC dissolve in 300mL methylenedichloride) was added slowly at 40-45°C for 2-3 hrs. The reaction was maintained for 3hours at 40 – 45°C. After completion of the reaction, water (500 mL) was added, separated the organic layer and distilled out methylene dichloride at atmospheric pressure. Finally, strip out the methylene dichloride by using isopropyl alcohol (200 mL). Isopropyl alcohol (1000 mL) was added to the distillate and maintained the stirring for 60 minutes at 70- 80°C. Cooled the mass to 30 – 35°C, filtered and washed with Isopropyl alcohol to get title compound 3 (yield 145 g). Example – 4: Preparation of 4-Amino-N-(2R, 3S) (3-amino-2-hydroxy-4-phenylbutyl)-N- isobutyl-benzene sulfonamide (1).

(1S, 2R)-{1-benzyl-2-hydroxy-3-[isobutyl-(4-nitro-benzenesulfonyl)-amino]-propyl}-carbamic acid tert-butyl ester (3, 100g), 10% palladium carbon (10gm) and triethanolamine (2gm) were suspended in isopropyl alcohol. The reaction was heated to 40 – 45°C and maintained under 4 – 6kg/cm2 of hydrogen pressure for 3 hours. After completion of reaction, the mass was filtered and hydrochloric acid (70mL) was added to the filtered mass. The solution was heated to reflux and maintained for 2-3hours. After completion of reaction the mass was cooled to 25-35°C, the reaction mass pH was adjusted to 6.0 – 7.0 with 20% sodium hydroxide solution and distilled out isopropyl alcohol under vacuum at below 55°C. Ethanol (200mL) and water (400mL) was added to the distillate, the mass pH was adjusted to 9.0 – 10.0 with 20% sodium hydroxide solution at 25-35°C and maintained the stirring for 2 hours at 25-35°C. The mass was cooled to 0 – 5°C, filtered and wash with water. The wet product was taken into ethanol (350mL), maintained the stirring for 30minutes at reflux temperature. The mass was cooled to 2 – 4°C, stirred for 2 hours, filtered and washed with ethanol (50 mL). The wet product was dried under normal drying to get title compound 1 (Yield 60 g).

Example-5: Preparation of ethyl-2-(4,5-dihydrofuran-3-yl)-2-oxoacetate (VI).

2, 3-Dihydrofuran (250 g) was taken in toluene (2000 mL) and triethyl amine (505 g) was added to above solution. Ethyl oxalyl chloride (536.5 g) was slowly added to the above mixture by maintaining temperature at 25-30°C and maintained the stirring for 5 hours. After completion of reaction separated the organic layer, washed the organic layer with 8% sodium bicarbonate solution (2x500mL). Organic layer was distilled completely under vacuum to get title compound VI (Yield 560g).

1 H NMR : 1.38 (t, 3H), 2.93 (t, 2H), 4.34 (q, 2H), 4.63 (t, 2H), 8.02 (s, 1 H).

Example-6: Preparation of ethyl-2-(3-bromo-2-ethoxytetrahydrofuran-3-yl)-2-oxoacetate (V).

Ethyl-2-(4,5-dihydrofuran-3-yl)-2-oxoacetate (Vl, 100g) was dissolved in dichloromethane (500ml) and Ethanol (150mL) was added. The reaction mass was cooled to 5 to 10°C. N- bromosuccinimide (1 15 g) was added lot wise by maintaining temp below 10°C. Reaction mass was then stirred at 20-30°C till completion of reaction. Reaction mass was washed with sodium bicarbonate solution (2%, 3x400mL) and the organic layer was used for the next step.

Example-7: Preparation of hexahydrofuro [2, 3-b] furan-3-ol (IV).

To the solution of Ethyl-2-(3-bromo-2-ethoxy tetra hydrofuran-3-yl)-2-oxoacetate in dichloromethane (V, 500mL) as prepared in above example, sodium sulphite solution (225g was dissolved in 1700mL of water) was added at 25-35°C. Reaction mass was stirred for 5-8hours at the same temperature and separated the organic and aqueous layers. Organic layer was washed with water (340mL). Distilled out the solvent completely get ethyl-2-(2-ethoxy tetra hydrofuran-3- yl)-2-oxoacetate. Sodium borohydride (35.5g)was dissolved in ethanol (400mL) under nitrogen atmosphere, ethyl-2-(2-ethoxytetra hydrofuran-3-yl)-2-oxoacetate was dissolved in ethanol (100mL) and slowly added to above solution at 15-30°C. Reaction mass was heated to 30-45X, maintained for 5-8 hours, the reaction mass temperature was raised to 55°C and stirred for 8 hours. The reaction mass was cooled to 20-30°C, ammonium chloride solution (1 5g in 200mL water) was slowly added and stirred for 1-2hours. The reaction mass was filtered and filtrate was distilled out under vacuum to get residue. Dichloromethane (600mL) was added to residue and cooled to -10°C. Hydrochloric acid (85mL) was added slowly drop wise in 2 hours by maintaining temp -5 to 0°C, reaction mass was stirred for 60minutes at -5 to 0°C and distilled the solvent completely. The obtained residue was stripped out with isopropyl alcohol (2x200mL, 1x100mL), ethyl acetate (500mL) was added to the resultant residue, stirred for 30-60minutes and cooled to 10-15°C. The solution was filtered and filtrate was concentrated to get title compound IV (yield 56 g).

Example-8: Preparation of Hexahydrofuro [2, 3-b] furan-3-yl acetate (III).

Hexahydrofuro [2, 3-b] furan-3-ol (IV, 60g) was dissolved in dichloromethane (300mL) and cooled to 0-5°C. To the cooled solution triethylamine (58.2 g), N, N-dimethylaminopyridine (1.12g) was added, acetic anhydride (56.5g) was added for 30-60 minutes at the same temperature, the mass temperature was raised to 25-35°C and stirred for 2-4hours. After completion of reaction the mass was cooled to 10-20°C, water (120mL) was added, stirred for 30minutes, separated the organic layer, washed with 10% sodium chloride solution (120mL) and distilled out dichloromethane to get title compound (yield 72g). Further, the product was purified by fractional distillation to get pure Hexahydrofuro [2, 3-b] furan-3-yl acetate III (yield 54g).

1 H NMR : 1.9-2.09(m, 2H), 2.10(s, 3H), 3.0-3.1 (m, 1 H), 3.86-4.03(m, 2H), 3.73(dd, 1 H), 4.10(dd, 1 H), 5.19(m, 1 H), 5.72 (d, 1 H)

Example-9: Preparation of (3R, 3aS, 6aR)-Hexahydrofuro [2, 3-b] furan-3-yl acetate (II). To the buffer solution (104.3g of sodium dihydrogen orthophosphate dissolved in 530mL of water & pH adjusted to 6.0-6.5 with saturated sodium bicarbonate solution(68g in 680 mL water) solution) hexahydrofuro [2, 3-b] furan-3-yl acetate (111,115g) and CAL-B (17.25g) was added at 25-35°C, heated to 38-45°C and stirred for 24 hours. CAL-B (17.25g) was added stirred for 16 hours, again CAL- B (11.5g) was added at 38-45°C and stirred for 16 hours (pH should maintain 6.0-6.5). The reaction mass was cooled to 20-30°C, methylenedichloride (1 150mL) was added to the mass and stirred for 30 minutes. The reaction mass was filtered through hyflowbed then separated the organic layer and washed with 10%sodiumchloride solution (575mL). Organic layer was distilled completely under vacuum to get title compound II (yield 40. Og). Example-10: Preparation of (3R, 3aS, 6aR)-Hexahydrofuro [2, 3-b] furan-3-ol (I).

(3R, 3aS, 6aR)-Hexahydrofuro [2, 3-b] furan-3-yl acetate (II, 14.0g) was dissolved in methanol (42mL). Potassium carbonate (0.34g) was added and stirred at 25-35°C for 6-8hours. Methanol was distilled out completely under vacuum, to the distillate methylenedichloride (28mL) was added, stirred the mass for 30 minutes and again distilled the solvent to get residue. Dissolved the residue in dichloromethane (56mL), the resultant solution was treated with carbon and the solvent was completely distilled out get title compound I (yield 10.5g). Example-11 : Preparation of (3R, 3aS, 6aR)-Hexahydrofuro [2, 3-b]-furan-3-yl-4-nitrophenyl carbonate (2).

To the solution of (3R, 3aS, 6aR)-Hexahydrofuro [2, 3-b] furan-3-ol (l,100g) and Bis-nitrophenyl carbonate (257.2g) in methylene dichloride (1200mL), triethylamine solution (132 g in 300 mL of methylene dichloride) was added slowly at 20-30°C for 2-3hours. Maintained the reaction at the same temperature for 8-10hours, after completion of reaction water (500mL) was added for 30- 60minut.es and settled the reaction mass then separated the organic layer. Organic layer was washed with 10% acetic acid (100mL) and 10% sodium chloride solution (500mL), distilled the organic layer and co distilled with ethyl acetate (100mL). Ethyl acetate (300mL) was added to the distillate and heated to 50-55°C for 30-45minut.es to get clear solution, the solution was cooled to 5-10°C and maintained at the same temperature for 60 minutes. The obtained solid was filtered, washed with ethanol (100mL) and dried the wet material at 40-45°C for 10-14 hours to get title compound 2 (yield 160g). Example-12: Preparation of dimethylformamide solvate of Darunavir.

To a mixture of 4-amino-N-(2r,3S)(3-amino-2-hydroxy-4-phenylbutyl)-N-lsobutyl- benzenesulfonamide (1 ,25g) and N-methyl-2-pyrrolidinone (NMPO, 50mL), a solution of (3R,3aS,6aR)-Hexahydrofuro[2,3-b]-furan-3-yl-4-nitrophenyl carbonate (2, 8.85g) and N-methyl- 2-pyrrolidinone (75mL) was added at -5 to 0°C for 2 to 3 hours under nitrogen atmosphere. The mass temperature was slowly raised to 25 to 30°C and stirred for 6 to 8 hours. The reaction mass was quenched in to the solution of methylene chloride (125mL) and water (250mL) at 25-35°C for 30 to 45 minutes. Separated the organic layer followed by washed with 10% sodium carbonate solution (150mL), 10% sodium chloride solution (150mL) and with water (6x150mL). Organic layer was dried over sodium sulphate and distill off the solvent under vacuum at below 50°C to obtain darunavir as a residue. To the residue Ν,Ν-dimethyl formamide (50mL) was added and cooled to 0 to -5°C, water (25mL) was added to the solution and maintained for 12hours at 0 to -5 °C, the obtained solid was filtered and washed with pre-cooled mixture of N,N-dimethyl formamide & water (25mL+25mL) to get dimethylformamide solvate of darunavir.

Example-13: Preparation of non-solvated crystalline Darunavir.

To a mixture of 4-amino-N-(2r,3S)(3-amino-2-hydroxy-4-phenylbutyl)-N-lsobutyl- benzenesulfonamide (1, 25g) and N-methyl-2-pyrrolidinone (NMPO, 50mL), a solution of (3R,3aS,6aR)-Hexahydrofuro[2,3-b]-furan-3-yl-4-nitrophenyl carbonate (2, 18.85g) and N- methyl-2-pyrrolidinone (75mL) was added at -5 – 0°C for 2 to 3 hours under nitrogen atmosphere. The mass temperature was slowly raised to 25 – 30°C and stirred for 6 to 8 hours. The reaction mass was quenched in to the solution of methylene chloride (250mL) and water (250mL) at 25- 35°C for 30 – 45 minutes. Separated the organic layer followed by washed with 10% potassium carbonate solution (5x125mL), water (5x125mL), 20% sodium chloride solution (25mL), finally washed with 20% citric acid solution (125mL). The organic layer was treated with carbon and distilled off the solvent under vacuum at below 50°C to obtain darunavir as a residue. To the residue ethylacetate (250mL) was added and cooled to 0 to -5°C, to the cooled solution hexane (225mL) was added and maintained for 12hours at 0 to -5 °C, the obtained solid was filtered, washed with pre-cooled mixture of ethylacetate and hexane (25mL+25mL) and dried the compound to get non-solvated crystalline darunavir(yield 25g).

Example -14: Preparation of Amorphous Darunavir.

Darunavir (200g) as obtained in above example was dissolved in methylene dichloride (10L) and washed with water (3×1000 mL). Organic layer was taken into agitated thin film dryer (ATFD) feed tank. Applied initial temperature about 36 – 40°C and high vacuum (580mm/Hg) to the vessel. Slowly feed the solution to the Vessel (feed rate 5L r) over 1hour finally given the methylene chloride (3L) flushing. The material is collected in the material collecter. Dried at 58 -62°C for 40 hours to get amorphous darunavir (yield 160g).

………………..

http://www.google.com/patents/WO2011048604A2?cl=en

Figure imgf000010_0001

Preparation of Durumvir ethanolate

A solution of (3R,3aS,6a ?)-hexahydrofuro[2,3-D]furan-3-yl 4-nitrophenyl carbonate (5b, 75.4 g) in A -methyl-2-pyrrolidinone (300 mL) was added to a pre-cooled (-2 ± 2°C) solution of the compound of formula 4 (100 g) in W-methyl-2-pyrrolidinone (200 mL) at -4 to 0°C over a period of 2 h. The temperature of the reaction mass was slowly raised to 25 – 30°C and maintained for 8 h. After completion of the reaction (TLC monitoring), ethyl acetate (1000 mL) and purified water (500 mL) were added to the reaction mass. The layers were separated; organic layer was washed with sodium carbonate solution (2 X 500 mL) followed by sodium chloride solution. The organic layer was concentrated; ethanol (300 mL) was added, heated to 45 – 50°C, maintained for 1 h, filtered and washed with ethanol. The wet compound was taken into a mixture of ethyl acetate- ethanol (7:93, 600 mL), heated to reflux, charcoal was added and filtered. The resultant filtrate was cooled to 0 – 5°C, filtered the separated solid and washed with ethanol. The wet compound was dried at 45°C to obtain the in 124.3 g (yield-82.5%). The obtained Darunavir ethanolate had purity of 99.79% on area by HPLC and contained 0.08% on area by HPLC of the difuranyl impurity. Preparation of Amorphous Darunavir

Example – 4

A solution of Darunavir ethanolate (200 g) in dichloromethane (10 L) was taken into ATFD Feed tank. The solvent was evaporated by fed the solution slowly to the ATFD Vessel (feed rate 5 L /h) at 36 – 40°C and high vacuum (580 mm/Hg) over 2 h and then flushed with dichloromethane (3 L). The material is collected in the material collector in 160g with the HPLC Purity of 99.60% and particle size D50 of approximately 50 micrometers and Dgo of approximately 100 to 180 micrometers. Example-5

Darunavir Ethanolate (200 gm) was dissolved in Methylene chloride (1000 ml) and solvent was evaporated by applying vacuum followed by isolation of amorphous Darunavir as a solid as such or by charging n-Heptane or Isopropyl ether. Example – 6

Darunavir Ethanolate (10 g) was dissolved in ethyl acetate (50 mL). The solution was heated to 40 – 45°C and maintained for 30 min. Ethyl acetate was distilled off under vacuum completely to get residue in the form of semisolid. n-Heptane (50 mL) was added to the residue and stirred for 30 min. at ambient temperature. The separated solid was filtered, washed the wet cake with n-heptane (5 mL) and dried at 40 – 45°C under vacuum to get 8.0 g of amorphous Darunavir.

Example – 7

Darunavir Ethanolate (10 g) was placed into a dry round bottom flask and heated to 110 – 120°C to melt and maintained under vacuum for 4 h. The reaction mass was slowly cooled to 25 – 35°C. The obtained glass type crystal was broken into powder to afford 8.5 g of amorphous Darunavir.

Example – 8

Darunavir Ethanolate (5.0 g) was suspended into glycerol (25 g), heated to 110 – 120°C under vacuum and maintained for 30min. Water (50 mL) was added to the cooled reaction mass at 25 – 35°C under stirring and the obtained suspension was stirred for 30 min at 25 – 35°C. The separated solid was filtered and dried at 40 – 45°C under vacuum to yield 3.5 g of amorphous Darunavir. Example – 9

Carbonic acid [(1 R,2S)-1-{((4-amino-benzenesulfonyl)-isobutyl-amino)-methyl}-2- ((3/?,3aS,6aR)-hexahydro-furo[2,3-ft]furan-3-yloxycarbonylamino)-3-phenyl-propylester (3R,3aS,6a ?)-hexahydro-furo[2,3- )]furan-3-yl ester (difuranyl impurity, 1).

The difuranyl impurity (1) isolated from the mother liquor by preparative HPLC using a mixture of formic acid-water (1 :99) as eluent. The 1H-NMR, 13C-NMR and mass spectral data complies with proposed structure.

1H-NMR (DMSO-cfe, 300 MHz, ppm) – δ 0.79 (d, J=6.6 Hz, 6H, 15 & 15′), 1.14-1.20 (m, 1 H, 20Ha), 1.34-1.42 (m, 1 H, 20Hb), 1.75-1.85 (m, 2H, 20’Ha & 14), 1.94-2.01(m, 1 H, 20’Hb), 2.54-2.64 (m, 2H, 8Ha & 13Ha), 2.74-2.89 (m, 3H, 8Hb, 13Hb & 19), 3.00-3.11 (m, 2H, 5Ha & 19′), 3.34-3.39 (m, 1H, 5Hb), 3.54-2.63 (m, 3H, 21 Ha & 17Ha), 3.65-3.74 (m, 3H, 21’Ha, 21 Hb &17Hb), 3.81-3.89 (m, 2H, 21’Hb & 17’Ha), 3.94-4.04 (m, 2H, 7 & 17’Hb), 4.81-4.88 (m, 1 H, 6), 4.92-4.96 (m, 1 H, 18′), 5.03-5.10 (m, 1 H, 18), 5.11 (d, J=5.4 Hz, 1 H, 22′), 5.61 (d, J=5.1 Hz, 1 H, 22), 6.03 (brs, 2H, NH2, D20 exchangeable), 6.63 (d, J=8.7 Hz, 2H, 2 & 2″), 7.15-7.28 (m, 5H, 10H, 10Ή, 11 H, 11′ & 12), 7.40 (d, J=8.7 Hz, 2H, 3 & 3′), 7.55 (d, J=9.3 Hz, 1 H, NH, D20 exchangeable).

“H-NMR (DMSO-d6, 75 MHz, ppm)- δ 19.56 & 19.81 (15C & 15’C), 25.42 (20 ), 25.47 (20C), 26.28 (14C), 35.14 (8C), 44.45(19’C), 45.01 (19C), 49.21 (5C), 53.39 (7C), 57.55 (13C), 68.70 (21 ‘C), 68.74 (21C), 69.95 (17’C), 70.20(17C), 72.65 (6C), 76.27 (18C), 79.59 (18’C), 108.70 (22’C), 108.75 (22C), 112.69 (2C), 122.56 (4C), 126.12 (12C), 128.04 (11 C & 11’C), 129.03 (10C & 10’C), 129.08 (3C), 138.03 (9C), 152.99 (1C), 153.55 (16’C), 155.32 (16C).

DIP MS: m/z (%) 1108 [M+Hf, 1131 [M+Naf

……………

http://www.google.com/patents/US20130244297

Figure US20130244297A1-20130919-C00025

According to the present invention Darunavir having the below impurity not more than 0.1, preferably 0.05%.

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DARUNAVIR

CHYAVAN PRASH DABUR ; AN EVALUATION OF AYURVEDIC REMEDY IN K.P.C.A.R.C. LABORATORY TEST


Dr.D.B.Bajpai's avatar**आधुनिक युग आयुर्वेद ** ई०टी०जी० आयुर्वेदास्कैन ** DIGITAL AYURVEDA TRIDOSHO SCANNER**AYURVED H. T. L. WHOLE-BODY SCANNER**आयुषव्यूज रक्त केमिकल केमेस्ट्री परीक्षण अनालाइजर ** डिजिटल हैनीमेनियन होम्योपैथी स्कैनर **

CHYAVAN PRASH is an AYURVEDIC REMEDY used as RASAYANA in Ayurveda. The PRASH is also used as a Food or Food Supplement for maintaining GENERAL HEALTH CONDITION [GHC].
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Above DABUR CHYAVAN PRASH container, which is tested at our Laboratory for evaluation puurposes.
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Dabur branded CHYAVAN PRASH is taken randomised examination and test for evaluation of AYURVEDIC FUNDAMENTALS.The batch number of the test material container is given above.

5 gramms DABUR CHYAVAN PRASH is taken for test and examination purposes and absorbed in 100 ml solvent, used for the liquification level for laboratory test.
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For Physical test and texture of the CHYAVAN PRASH, as for as prepared by me few years ago, on the similar lines , which was laid down and instructed by CHARAK SAMHITA. Although I prepared several years CHYAVAN PRASH for my patient, therefore I know well about the taste and texture of the Chyavan Prash.

A well…

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