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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

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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.
OLYMPUS DIGITAL CAMERA

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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Medicinal Chemistry International: ASUNAPREVIR


Medicinal Chemistry International: ASUNAPREVIR

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ASUNAPREVIR

ASUNAPREVIR
THERAPEUTIC CLAIM Treatment of hepatitis C
CHEMICAL NAMES
1. Cyclopropanecarboxamide, N-[(1,1-dimethylethoxy)carbonyl]-3-methyl-L-valyl-(4R)-4-[(7-chloro-4-methoxy-1-isoquinolinyl)oxy]-L-prolyl-1-amino-N-(cyclopropylsulfonyl)-2-ethenyl-, (1R,2S)-
2. 1,1-dimethylethyl [(1S)-1-{[(2S,4R)-4-(7-chloro-4methoxyisoquinolin-1-yloxy)-2-({(1R,2S)-1-[(cyclopropylsulfonyl)carbamoyl]-2-ethenylcyclopropyl}carbamoyl)pyrrolidin-1-yl]carbonyl}-2,2-dimethylpropyl]carbamate
MOLECULAR FORMULA C35H46ClN5O9S
MOLECULAR WEIGHT 748.3
SPONSOR Bristol-Myers Squibb
CODE DESIGNATION ………..BMS-650032
CAS REGISTRY NUMBER 630420-16-5
ChemSpider 2D Image | asunaprevir | C35H46ClN5O9S
Asunaprevir (formerly BMS-650032) is an experimental drug candidate for the treatment of hepatitis C. It is undergoing development by Bristol-Myers Squibb and is currently inPhase III clinical trials.[1]
In 2013, the company Bristol-Myers Squibb received breakthrough therapy designation in the U.S. for the treatment of chronic hepatitis C in combination with daclatasvir and BMS-791325.
Asunaprevir is an inhibitor of the hepatitis C virus enzyme serine protease NS3.[2]
Asunaprevir is being tested in combination with pegylated interferon and ribavirin, as well as in interferon-free regimens with other direct-acting antiviral agents includingdaclatasvir[3][4][5]
Asunaprevir is an antiviral agent originated by Bristol-Myers Squibb undergoing the registration in Japan for the treatment of chronic hepatitis C virus infection in combination with daclatasvir in patients who are non-responsive to interferon plus ribavirin and interferon based therapy ineligible naive/intolerant
  1. “A Phase 3 Study in Combination With BMS-790052 and BMS-650032 in Japanese Hepatitis C Virus (HCV) Patients”ClinicalTrials.gov.
  2. C. Reviriego (2012). Drugs of the Future 37 (4): 247–254.doi:10.1358/dof.2012.37.4.1789350.
  3.  Preliminary Study of Two Antiviral Agents for Hepatitis C Genotype 1. Lok, A et al. New England Journal of Medicine. 366(3):216-224. January 19, 2012.
  4.  “Bristol-Myers’ Daclatasvir, Asunaprevir Cured 77%: Study”Bloomberg. Apr 19, 2012.
  5. AASLD: Daclatasvir plus Asunaprevir Rapidly Suppresses HCV in Prior Null Responders. Highleyman, L. HIVandHepatitis.com. 8 November 2011.
  6. Bioorganic and Medicinal Chemistry Letters, 2011 ,  vol. 21,   7  pg. 2048 – 2054

patents
WO 2003099274, WO 2003099274, WO 2009085659

US8202996 6-20-2012 Crystalline forms of N-(tert-butoxycarbonyl)-3-methyl-L-valyl-(4R)-4-((7-chloro-4-methoxy-1-isoquinolinyl)oxy)-N- ((1R,2S)-1-((cyclopropylsulfonyl)carbamoyl)-2-vinylcyclopropyl)-L-prolinamide
US8163921 4-25-2012 Hepatitis C Virus Inhibitors
US7915291 3-30-2011 HEPATITIS C VIRUS INHIBITORS
US7449479 11-12-2008 Hepatitis C virus inhibitors
US6995174 2-8-2006 Hepatitis C virus inhibitors
……….
Hepatitis C virus (HCV) is a major human pathogen, infecting an estimated 170 million persons worldwide—roughly five times the number infected by human immunodeficiency virus type 1. A substantial fraction of these HCV infected individuals develop serious progressive liver disease, including cirrhosis and hepatocellular carcinoma.
Presently, the most effective HCV therapy employs a combination of alpha-interferon and ribavirin, leading to sustained efficacy in 40 percent of patients. Recent clinical results demonstrate that pegylated alpha-interferon is superior to unmodified alpha-interferon as monotherapy. However, even with experimental therapeutic regimens involving combinations of pegylated alpha-interferon and ribavirin, a substantial fraction of patients do not have a sustained reduction in viral load. Thus, there is a clear and unmet need to develop effective therapeutics for treatment of HCV infection.
Figure US08338606-20121225-C00018
Figure US08338606-20121225-C00019
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Compound 277
Compound 277 was prepared by following Scheme 2 of Example 269 except that 3- (4-chloro-phenyl)-3-methoxy-acrylic acid was used in place of 2- trifluormethoxycinnamic acid in step 1.
Step 1:
Modifications: 4.24 g 3-(4-chloro-phenyl)-3-methoxy-acrylic acid used, 130 mg product obtained (3% yield) Product:
Figure imgf000383_0002
Data: 1H NMR(400 MHz, CD3OD) δ ppm 3.96 (s, 3 H), 7.19 (dd, 7=8.80, 2.45 Hz, 1 H), 7.28 (d, 7=2.45 Hz, 1 H), 7.34 (s, 1 H), 8.25 (d, 7=9.05 Hz, 1 H); MS: (M+H)+ 210.
Step 2:
Modifications: 105 mg 7-chloro-4-methoxy-2H-isoquinolin-l-one used, 60 mg product obtained (71% yield). Product:
Figure imgf000384_0001
Data: Η NMR (400 Hz, CDC13) δ ppm 4.05 (s, 3 H), 7.67 (dd, 7=8.80, 1.96 Hz, 1 H), 7.80 (s, 1 H), 8.16 (d, 7=9.05 Hz, 1 H), 8.24 (d, 7=1.96 Hz, 1 H); MS: (M+H)+ 229.
Step 3:
Modifications: 46 mg l,7-dichloro-4-methoxy-isoquinoline and 113 mg { l-[2-(l- cyclopropanesulfonylaminocarbonyl-2-vinyl-cyclopropylcarbamoyl)-4-hydroxy- pyrrolidine-1 -carbon yl]-2,2-dimethyl-propyl} -carbamic acid tert-butyl ester used, 50 mg product obtained (31% yield). Product:
Figure imgf000384_0002
Compound 277
Data: 1H NMR (400 Hz, CD3OD) δ ppm 1.06 (m, 11 H), 1.16 (s, 9 H), 1.24 (m, 2 H), 1.44 (dd, 7=9.54, 5.38 Hz, 1 H), 1.88 (dd, 7=8.07, 5.62 Hz, 1 H), 2.28 (m, 2 H), 2.59 (dd, 7=13.69, 6.85 Hz, 1 H), 2.94 (m, 1 H), 4.00 (s, 3 H), 4.05 (d, 7=11.74 Hz, 1 H), 4.19 (s, 1 H), 4.43 (d, 7=11.49 Hz, 1 H), 4.56 (dd, 7=10.03, 6.85 Hz, 1 H), 5.12 (d, 7=11.49 Hz, 1 H), 5.30 (d, 7=17.12 Hz, 1 H), 5.76 (m, 2 H), 7.57 (s, 1 H), 7.67 (d, 7=8.56 Hz, 1 H), 8.04 (s, 1 H),  8.08 (d, 7=8.80 Hz, 1 H); MS: (M+H)+ 749.
…………..
Figure US06995174-20060207-C00021
Figure US06995174-20060207-C00022
………………
WO 2003099274
Figure US06995174-20060207-C00038
…………………….
Figure US20090202476A1-20090813-C00018
Figure US20090202476A1-20090813-C00019
Preparation of Compound C
DMSO (264 ml) was added to a mixture of Compound A (6 g, 26.31 mmol, 1.0 eq, 96.5% potency), Compound B (6.696 g, 28.96 mmol, 1.1 eq) and KOtBu (8.856 g, 78.92 mmol, 3 eq) under nitrogen and stirred at 36° C. for 1 h. After cooling the dark solution to 16° C., it was treated with water (66 ml) and EtOAc (132 ml). The resulting biphasic mixture was acidified to pH 4.82 with 1N HCl (54 ml) at 11.2-14.6° C. The phases were separated. The aqueous phase was extracted once with EtOAc (132 ml). The organic phases were combined and washed with 25% brine (2×132 ml). Rich organic phase (228 ml) was distilled at 30-40° C./50 mbar to 37.2 ml. A fresh EtOAc (37.2 ml) was added and distilled out to 37.2 ml at 30-35° C./50 nm bar. After heating the final EtOAc solution (37.2 ml) to 50° C., heptane ((37.2 ml) was added at 46-51° C. and cooled to 22.5° C. over 2 h. It was seeded with 49 mg of Compound C and held at 23° C. for 15 min to develop a thin slurry. It was cooled to 0.5° C. in 30 min and kept at 0.2-0.5° C. for 3 h. After the filtration, the cake was washed with heptane (16.7 ml) and dried at 47° C./80 mm/15.5 h to give Compound C as beige colored solids (6.3717 g, 58.9% corrected yield, 99.2% potency, 97.4 AP).
Preparation of Compound E
DIPEA (2.15 ml, 12.3 mmol, 1.3 eq followed by EDAC (2 g, 10.4 mmol, 1.1 eq) were added to a mixture of Compound C (4 g, 9.46 mmol, 97.4% potency, 98.5 AP), Compound D (4.568 g, 11.35 mmol, 1.20 eq), HOBT-H2O (0.86 g, 4.18 mmol, 0.44 eq) in CH2Cl(40 ml) at 23-25° C. under nitrogen. The reaction was complete after 3 h at 23-25° C. It was then washed with 1N HCl (12 ml), water (12 ml) and 25% brine (12 ml). MeOH (80 ml) was added to the rich organic solution at 25° C., which was distilled at atmospheric pressure to ˜60 ml to initiate the crystallization of the product. The crystal slurry was then cooled from 64° C. to 60° C. in 5 min and stirred at 60° C. for 1 h. It was further cooled to 24° C. over 1.5 h and held at 24° C. for 2 h. After the filtration, the cake was washed with MeOH (12 ml) and dried at 51° C./20-40 nm i/18 h to give Compound E (5.33 g, 89% yield, 97.7% potency, 99.1 AP).
Preparation of Compound F
5-6N HCl in IPA (10.08 ml, 50.5 mmol, Normality: 5N) was added in four portions in 1 h to a solution of Compound E (8 g, 12.6 mmol, 97.7% potency, 99.1 AP) in IPA (120 ml) at 75° C. After stirring for 1 h at 75° C., the resulting slurry was cooled to 21° C. in 2 h and stirred at 21° C. for 2 h. It was filtered and the cake was washed with IPA (2×24 ml). The wet cake was dried at 45° C./House vacuum/16 h to give Compound F as an off-white solid (6.03 g, 84.5% yield, 98.5% potency, 100 AP).
Preparation of Compound (I)
DIPEA (9.824 ml) followed by HATU (7.99 g) were added to a stirred mixture of Compound F (10 g, 99.2% potency, 99.6 AP) and Compound G (4.41 g) in CH2Cl(100 ml) at 2.7-5° C. under nitrogen. The resulting light brown solution was stirred at 0.2-3° C. for 1.5 h, at 3-20° C. in 0.5 h and at 20-23° C. for 15.5 h for a reaction completion. It was quenched with 2N HCl (50 ml) at 23° C. and stirred for 20 min at 23-24° C. The biphasic mixture was polish filtered through diatomaceous earth (Celite®) (10 g) to remove insoluble solids of HOAT and HATU. The filter cake was washed with 20 ml of CH2Cl2. After separating the organic phase from the filtrates, it was washed with 2N HCl (5×50 ml) and water (2×50 ml). The organic phase (115 ml) was concentrated to ˜50 ml, which was diluted with absolute EtOH (200 proof, 100 ml) and concentrated again to ˜50 ml. Absolute EtOH (50 ml) was added to bring the final volume to 100 ml. It was then warmed to 50° C. to form a clear solution and held at 50° C. for 35 min. The ethanolic solution was cooled from 50 to 23° C. over 15 min to form the crystal slurry. The slurry was stirred at 23 CC for 18 h, cooled to 0.3° C. over 30 min and kept at 0.2-0.3° C. for 2 h. After the filtration, the cake was washed with cold EtOH (2.7° C., 2×6 ml) and dried at 53° C./72 mm/67 h to give Compound (I) in Form T1F-1/2 as an off white solid (10.49 g, 80.7% yield, 99.6 AP).https://www.google.co.in/patents/US20090202476?dq=WO+2009085659&ei=dzy5UpL_LMXXrQewxYG4Dw&cl=en
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extra info
Hepatitis C virus (HCV) infection is the principal cause of chronic liver disease that can lead to cirrhosis, carcinoma and liver failure.1 More than 200 million people worldwide are chronically infected by this virus. Currently, the most effective treatment for HCV infection is based on a combination therapy of injectable pegylated interferon-α (PEG IFN-α) and antiviral drug ribavirin. This treatment, indirectly targeting the virus, is associated with significant side effects often leading to treatment discontinuation in certain patient populations.2 In addition, this treatment regimen cures only less than 50% of patients infected with genotype-1 which is the predominant genotype (while genotype 1a is most abundant in the US, the majority of sequences in Europe and Japan are from genotype 1b).3 Limited efficacy and adverse side effects of current treatment, and high prevalence of infection worldwide highlight an urgent need for more effective, convenient, and well-tolerated treatments.4
HCV NS3 serine protease plays a critical role in the HCV replication by cleaving downstream sites (with the assistance of the cofactor NS4A) along the HCV viral polyprotein to produce functional proteins. Recently, NS3/4A protease inhibitors have emerged as a promising treatment for HCV infection.5 There are two distinct classes of NS3 protease inhibitors in clinical development. The first class is comprised of serine-trap inhibitors, exemplified by VX-950 (telaprevir)6 and SCH-503034 (boceprevir).7 The second class is represented by reversible noncovalent inhibitors such as macrocyclic inhibitors BILN-2061 (ciluprevir),8 ITMN-191 (danoprevir),9 TMC-43535010 and MK-7009 (vaniprevir).11 Due to concern over cardiac issues in animals treated with macrocyclic BILN-2061,12 newer acyclic inhibitors have recently been developed exemplified by BI-20133513 and BMS-650032.14 However, a rapid development of viral resistance has been observed for patients treated with HCV NS3 protease inhibitors.15 Therefore, the discovery of new NS3 protease inhibitors with novel binding paradigm and thus potentially differentiated resistance profile is highly desirable.

REFERENCES AND NOTES

    • F. Zoulim, M. Chevallier, M. Maynard, C. Trepo
    • Rev. Med. Virol., 13 (2003), p. 57
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    • B.L. Pearlman
    • Am. J. Med., 117 (2004), p. 344
    • (a) R. Flisiak, A. Parfieniuk
    • For a recent review on HCV anti-viral agents, see: Expert Opin. Invest. Drugs, 19 (2010), p. 63
    • (b) A.D. Kwong, L. McNair, I. Jacobson, S. George
    • Curr. Opin. Pharmacol., 8 (2008), p. 522
    • (a) K.X. Chen, F.G. Njoroge
    • For a recent review on HCV NS3/4A protease inhibitors, see: Curr. Opin. Invest. Drugs, 10 (2009), p. 821
    • (b) M. Reiser, J. Timm
    • Expert Rev. Anti. Infect. Ther., 7 (2009), p. 537
    • C. Lin, A.D. Kwong, R.B. Perni
    • Infect. Disord. Drug Targets, 6 (2006), p. 3
    • F.G. Njoroge, K.X. Chen, N.Y. Shih, J.J. Piwinski
    • Acc. Chem. Res., 41 (2008), p. 50
    • M. Llinàs-Brunet, M.D. Bailey, G. Bolger, C. Brochu, A.M. Faucher, J.M. Ferland, M. Garneau, E. Ghiro, V. Gorys, C. Grand-Maître, T. Halmos, N. Lapeyre-Paquette, F. Liard, M. Poirier, M. Rhéaume, Y.S. Tsantrizos, D. Lamarre
    • J. Med. Chem., 47 (2004), p. 1605
    • S.D. Seiwert, S.W. Andrews, Y. Jiang, V. Serebryany, H. Tan, K. Kossen, P.T. Rajagopalan, S. Misialek, S.K. Stevens, A. Stoycheva, J. Hong, S.R. Lim, X. Qin, R. Rieger, K.R. Condroski, H. Zhang, M.G. Do, C. Lemieux, G.P. Hingorani, D.P. Hartley, J.A. Josey, L. Pan, L. Beigelman, L.M. Blatt
    • Antimicrob. Agents Chemother., 52 (2008), p. 4432
    • P. Raboisson, H. de Kock, A. Rosenquist, M. Nilsson, L. Salvador-Oden, T.I. Lin, N. Roue, V. Ivanov, H. Wähling, K. Wickström, E. Hamelink, M. Edlund, L. Vrang, S. Vendeville, W. Van de Vreken, D. McGowan, A. Tahri, L. Hu, C. Boutton, O. Lenz, F. Delouvroy, G. Pille, D. Surleraux, P. Wigerinck, B. Samuelsson, K. Simmen
    • Bioorg. Med. Chem. Lett., 18 (2008), p. 4853
    • J.A. McCauley, C.J. McIntyre, M.T. Rudd, K.T. Nguyen, J.J. Romano, J.W. Butcher, K.F. Gilbert, K.J. Bush, M.K. Holloway, J. Swestock, B.L. Wan, S.S. Carroll, J.M. Dimuzio, D.J. Graham, S.W. Ludmerer, S.S. Mao, M.W. Stahlhut, C.M. Fandozzi, N. Trainor, D.B. Olsen, J.P. Vacca, N.J. Liverton
    • J. Med. Chem., 53 (2010), p. 2443
    • H. Hinrichsen, Y. Benhamou, H. Wedemeyer, M. Reiser, R.E. Sentjens, J.L. Calleja, X. Forns, A. Erhardt, J. Crönlein, R.L. Chaves, C.L. Yong, G. Nehmiz, G.G. Steinmann
    • Gastroenterology, 127 (2004), p. 1347
    • M. Llinàs-Brunet, M.D. Bailey, N. Goudreau, P.K. Bhardwaj, J. Bordeleau, M. Bös, Y. Bousquet, M.G. Cordingley, J. Duan, P. Forgione, M. Garneau, E. Ghiro, V. Gorys, S. Goulet, T. Halmos, S.H. Kawai, J. Naud, M.A. Poupart, P.W. White
    • J. Med. Chem., 53 (2010), p. 6466
    • (a)Chemical and Engineering News (April 12, 2010 issue), 88, pp 30–33.
    • (b)Perrone, R.K.; Wang, C.; Ying, W.; Song, A.I. WO 2009085659
    • L. Rong, H. Dahari, R.M. Ribeiro, A.S. Perelson
    • Sci. Transl. Med., 2 (2010), p. 30ra32
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Tariquidar » All About Drugs


Tariquidar » All About Drugs

Zosuquidar


LY335979(Zosuquidar)

LY335979, RS-33295-198  (Zosuquidar)

Roche Palo Alto (Originator)

LY335979 (Zosuquidar) is a selective Pgp (P-glycoprotein) inhibitor with a Ki of 59 nM. LY335979 significantly enhanced the survival of mice implanted with Pgp-expressing murine leukemia (P388/ADR) when administered in combination with either daunorubicin, doxorubicin or etoposide.


LY335979 (Zosuquidar)

M.Wt: 636.99

Formula: C32H31F2N3O2.3HCl

Name: Zosuquidar trihydrochloride

 Elemental Analysis: C, 60.34; H, 5.38; Cl, 16.70; F, 5.97; N, 6.60; O, 5.02

CAS : 167465-36-3

167354-41-8 (free base)

Roche Bioscience (Originator), Eli Lilly and Company (Licensee).

US5654304WO1994024107A1WO2000075121US6570016

Drug Des Discov 1992, 9(1): 69, Bioorg Med Chem Lett 1995, 5(21): 2473, Drugs Fut 2003, 28(2): 125

Zosuquidar is currently under development. It is now in “Phase 3” of clinical tests in the United States. Its action mechanism consists of the inhibition of P-glycoproteins; other drugs with this mechanism include tariquidar and laniquidar. P-glycoproteins are proteins which convert the energy derived from the hydrolysis of ATP to structural changes in protein molecules, in order to perform coupling, thus discharging medicine from cells. If P-glycoprotein coded with the MDR1 gene manifests itself in cancer cells, it discharges much of the antineoplastic drugs from the cells, making cancer cells medicine tolerant, and rendering antineoplastic drugs ineffective. This protein also manifests itself in normal organs not affected by the cancer (such as the liver, small intestine, and skin cells in blood vessels of the brain), and participates in the transportation of medicine. The compound Zosuquidar inhibits this P-glycoprotein, causing the cancer cells to lose their medicine tolerance, and making antineoplastic drugs effective

Clinicial trials: Clinical report published in 2010 showed that  zosuquidar did not improve outcome in older acute myeloid leukemia, in part, because of the presence P-gp independent mechanisms of resistance. (Blood. 2010 Nov 18;116(20):4077-85.)

Zosuquidar  is a potent P-glycoprotein inhibitor, which binds with high affinity to P-glycoprotein and inhibits P-glycoprotein-mediated multidrug resistance (MDR). P-glycoprotein, encoded by the MDR-1 gene, is a member of the ATP-binding cassette superfamily of transmembrane transporters and prevents the intracellular accumulation of many natural product-derived cytotoxic agents

Zosuquidar

U.S. Patent No. 5,112,817 to Fukazawa et al. discloses certain quinoline derivatives useful as anticancer drug potentiators for the treatment of multidrug resistance. One of the initially promising active agents there-disclosed is MS-073, which has the following structure:

Figure imgf000004_0001

MS-073

U.S. Pat. Nos. 5,643,909 and 5,654,304 disclose a series of 10,11- methanobenzosuberane derivatives useful in enhancing the efficacy of existing cancer chemotherapeutics and for treating multidrug resistance. One such derivative having good activity, oral bioavailability, and stability, is zosuquidar, a compound of formula (2R)-anti-5-

3 – [4-( 10, 11 -difluoromethanodibenzosuber-5-yl)piperazin- 1 -yl]-2-hydroxypropoxy) quinoline.

Figure imgf000010_0001

Zosuquidar

Given the limitations of previous generations of MDR modulators, three preclinical critical success factors were identified and met for zosuquidar: 1) it is a potent inhibitor of P-glycoprotein; 2) it is selective for P-glycoprotein; and 3) no pharmacokinetic interaction with co-administered chemotherapy is observed.

Zosuquidar is extremely potent in vitro (Kj = 59 nM) and is among the most active modulators of P-gp-associated resistance described to date. Zosuquidar has also demonstrated good in vivo activity in preclinical animal studies. In addition, the compound does not appear to be a substrate for P-gp efflux, resulting in a relatively long duration of reversal activity in resistant cells even after the modulator has been withdrawn.

Another significant attribute of zosuquidar as an MDR modulator is the minimal pharmacokinetic (PK) interactions with several oncolytics tested in preclinical models. Such minimal PK interaction permits normal doses of oncolytics to be administered and also a more straightforward interpretation of the clinical results.

Zosuquidar is generally administered in the form of the trihydrochloride salt. Conventional zosuquidar trihydrochloride formulations include those containing zosuquidar (50 mg as free base), glycine (15 mg), and mannitol (200 mg) dissolved in enough water for injection, to yield a free base concentration of 5 mg/mL. The formulation is filled into vials and lyophilized to give a vial containing 50 mg of free base. For such formulations, a 30 mL vial size is necessary to contain 50 mg of thezosuquidar formulation. For a typical >200 mg dose of zosuquidar, multiple 50 mg vials are needed to contain the formulation, greatly increasing manufacturing costs and reducing convenience for the end user {e.g., a pharmacist). Modified Cyclodextrins

Cyclodextrins are cyclic oligomers of glucose; these compounds form inclusion complexes with any drug whose molecule can fit into the lipophile-seeking cavities of the cyclodextrin molecule. See U.S. Pat. No. 4,727,064 for a description of various cyclodextrin derivatives. Cyclodextrins of preferred embodiments can include α-, β-, and χ-cyclodextrins. The α-cyclodextrins include six glucopyranose units, the β- cyclodextrins include seven glucopyranose units, and the χ-cyclodextrins include eight glucopyranose units. The β -cyclodextrins are generally preferred as having a suitable cavity size for zosuquidar. Cyclodextrin can be in any suitable form, including amorphous and crystalline forms, with the amorphous form generally preferred. Cyclodextrins suitable for use in the formulations of preferred embodiments include the hydroxypropyl, hydroxyethyl, glucosyl, maltosyl, and maltotrosyl derivatives of β- cyclodextrin, carboxyamidomethyl-β-cyclodextrin, carboxymethyl-β-cyclodextrin, and diethylamino-β-cyclodextrin.

Pharmaceutical complexes including various cyclodextrins and cyclodextrin derivatives are disclosed in the following United States patents: U.S. Pat. No. 4,024,223; U.S. Pat. No. 4,228,160; U.S. Pat. No. 4,232,009; U.S. Pat. No. 4,351,846; U.S. Pat. No. 4,352,793; U.S. Pat. No. 4,383,992; U.S. Pat. No. 4,407,795; U.S. Pat. No. 4,424,209; U.S. Pat. No. 4,425,336; U.S. Pat. No. 4,438,106; U.S. Pat. No. 4,474,881; U.S. Pat. No. 4,478,995; U.S. Pat. No. 4,479,944; U.S. Pat. No. 4,479,966; U.S. Pat. No. 4,497,803; U.S. Pat. No. 4,499,085; U.S. Pat. No. 4,524,068; U.S. Pat. No. 4,555,504; U.S. Pat. No. 4,565,807; U.S. Pat. No. 4,575,548; U.S. Pat. No. 4,598,070; U.S. Pat. No. 4,603,123; U.S. Pat. No. 4,608,366; U.S. Pat. No. 4,659,696; U.S. Pat. No. 4,623,641; U.S. Pat No. 4,663,316; U.S. Pat. No. 4,675,395; U.S. Pat. No. 4,728,509; U.S. Pat. No. 4,728,510; and U.S. Pat. No. 4,751,095.

Chemically modified and substituted α-, β-, and χ-cyclodextrins are generally preferred over unmodified α-, β-, and χ-cyclodextrins due to improved toxicity and solubility properties. The degree of substitution of the hydroxy 1 groups of the glucopyranose units of the cyclodextrin ring can affect solubility. In general, a higher average degree of substitution of substituent groups in the cyclodextrin molecule yields a cyclodextrin of higher solubility.

Examples for Pgp inhibitors are cyclosporine A, valpodar, elacridar, tariquidar, zosuquidar, laniquidar, biricodar, S-9788, MS-209, BIBW-22 (BIBW-22-BS) , toremifene, verapamil, dexverapamil , quinine, quinidine, trans- flupentixol, chinchonine and others (J. Roberts, C. Jarry (2003) : J. Med. Chem. 46, 4805 – 4817) . The list of inhibitors of P-glycoprotein is increasing (e.g. Wang et al . (2002) : Bioorg. Med. Chem. Lett. 12, 571 – 574) .

Figure imgf000005_0001

Figure 2: Structures of BIBW-22, MS-209 and S-9788

7-12-2000
10,11-methanodibenzosuberane derivatives
10-17-2007
Salt and crystalline forms of (2R)-anti-5-{3-[4-(10,11-difluoromethanodibenzosuber-5-yl)piperazin-1-yl]-2-hydroxypropoxy}quinoline
9-2-2009
Salt and crystalline forms of (2R)-anti-5-{3-[4-(10,11-difluoromethanodibenzosuber-5-YL)piperazin-1-YL]-2-hydroxypropoxy}quinoline

……………………

 

U.S. Pat. Nos. 5,643,909 and 5,654,304, incorporated herein by reference, disclose a series of 10,11-methanobenzosuberane derivatives useful in enhancing the efficacy of existing cancer chemotherapeutics and for treating multidrug resistance. (2R)-anti-5-{3-[4-(10,11-difluoromethanodibenzosuber-5-yl)piperazin-1-yl]-2-hydroxypropoxy}quinoline trihydrochloride disclosed therein, is currently under development as a pharmaceutical agent.

U.S. pat. No. 5,654,304 (‘304), incorporated by reference herein, discloses a series of 10,11-(optionally substituted)methanodibenzosuberane derivatives useful in enhancing, the efficacy of existing cancer chemotherapeutics and for treating multidrug resistance. (2R)-anti-5-{3-[4-(10,11-Difluoromethanodibenzosuber-5-yl)piperazin-1-yl]-2-hydroxypropoxy}quinolone trihydrochloride is disclosed in ‘304 and is currently under development as a pharmaceutical agent. WO00/75121 discloses Form I, a crystalline form of (2R)-anti-5-{3-[4-(10,11-difluoromethanodibenzosuber-5-yl)piperazin-1-yl]-2-hydroxypropoxy}quinolone trihydrochloride.

The art disclosed in U.S. Pat. No. 5,776,939, and U.S. Pat. No. 5,643,909 both incorporated herein by reference, and PCT Patent Applications (Publication numbers WO 94/24107 and 98/22112) teach the use of 1-formylpiperazine to introduce the piperazine group of the compound of formula II

Figure US06570016-20030527-C00002

Compound II is a mixture of syn isomer (III)

Figure US06570016-20030527-C00003

and anti isomer (IV)

Figure US06570016-20030527-C00004

The process as disclosed in U.S. Pat. Nos. 5,643,909 and 5,654,304 (represented by scheme A, below) involves (a) chromatographic separation(s) of the formyl piperazine compound; and (b) deformylation of the formyl piperazine compound to provide compound IV.https://www.google.co.in/patents/US6570016?cl=en

Figure US06570016-20030527-C00005

The process of the present invention uses piperazine to react with the (1aα,6α,10bα)-6-halo-1,1-difluoro-1,1a,6,10b-tetrahydrodibenzo[a,e]cyclopropa[c]-cycloheptene compound or derivative, instead of formylpiperazine.

The process of the present invention is advantageous because piperazine is readily available in commercial quantities whereas 1-formylpiperazine, which was utilized in the process disclosed in U.S. Pat. No. 5,643,909 is often not readily available in commercial quantities. Additionally piperazine enjoys a significant cost advantage over 1-formylpiperazine.

The use of piperazine instead of 1-formylpiperazine is a significant advancement over the prior art because it obviates the need to deformylate or hydrolyze off the formyl group (step 6, scheme A), thereby providing fewer operational steps. U.S. Pat. No. 5,643,909 teaches the separation of the 1-formylpiperazine compounds by chromatography or repeated crystallization. The present invention obviates the need for chromatographic separations of the formylpiperazine diastereomeric addition compounds (see step 4, scheme A)

Figure US06570016-20030527-C00018

Figure US06570016-20030527-C00019

EXAMPLES

The following examples and preparations are illustrative only and are not intended to limit the scope of the invention in any way.

Preparation 1 R-1-(5-Quinolinyloxy)-2,3-epoxypropane

Figure US06570016-20030527-C00022

A mixture of 5-hydroxyquinoline (5.60 g, 38.6 mmol), R-glycidyl nosylate (10.0 g, 38.6 mmol), powdered potassium carbonate (11.7 g, 84.9 mmol), and N,N-dimethylformamide (100 mL) was stirred at ambient temperature until HPLC analysis (40% acetonitrile/60% of a 0.5% aqueous ammonium acetate solution, 1 mL/min, wavelength=230 nm, Zorbax RX-C8 25 cm×4.6 mm column) indicated complete disappearance of glycidyl nosylate (approximately 6 hours). The reaction mixture was filtered through paper and the filter cake was washed with 200 mL of a 3:1 mixture of MTBE and methylene chloride. The filtrate was washed with 200 mL of water and the aqueous layer was extracted four times with 100 mL of 3:1 MTBE/methylene chloride. The combined organic layers were dried over 30 grams of magnesium sulfate and the dried solution was then stirred with 50 grams of basic alumina for 30 minutes. The alumina was removed by filtration and the filter cake was washed with 200 mL of 3:1 MTBE/methylene chloride. The filtrate was concentrated to a volume of 100 mL, 300 mL of MTBE were added, and the solution was again concentrated to 80 mL. After heating to 50° C., the solution was treated with 160 mL of heptane dropwise over 15 minutes, allowed to cool to 40° C., and seeded, causing the formation of a crystalline precipitate. The mixture was stirred for two hours at ambient temperature and then at 0-5° C. for an additional 2 hours. The crystals were filtered, washed with cold heptane, and dried to provide 5.68 g (73.2%) of (2R)-1-(5-quinolinyloxy)-2,3-epoxypropane as white needles.

mp 79-81° C.;

[α]25 D−36.4° (c 2.1, EtOH);

1H NMR (500 MHz, CDCl3)δ 2.83 (dd, J=4.8, 2.7 Hz, 1H), 2.97 (m, 1H), 3.48 (m, 1H), 4.10 (dd, J=11.0, 6.0 Hz, 1H), 4.43 (dd, J=11.0, 2.7 Hz, 1H), 6.85 (d, J=7.8 Hz, 1H), 7.38 (dd, J=8.5 Hz, 4.1 Hz, 1H), 7.59 (m, 1H), 7.71 (d, J=8.5 Hz, 1H), 8.61 (m, 1H), 8.90 (m, 1H).

Example 1 (2R)-Anti-1-[4-(10,11-difluoromethano-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5-yl)-piperazin-1-yl]-3-qunolin-5-yloxy)-propan-2-ol Trihydrochloride

Figure US06570016-20030527-C00023

Preparation of the above compound is exemplified in the following preparative steps.

Step 1 1,1-Difluoro-1a,10b-dihydrodibenzo[a,e]cyclopropa[c]-cyclohepten-6 (1H)-one

Figure US06570016-20030527-C00024

A solution of sodium chlorodifluoroacetate (350 g) in diglyme (1400 mL) was added dropwise over 4 to 8 hours, preferably over 6 hours, to a solution of 5H-dibenzo[a,d]cyclo-hepten-5-one (25 g) in diglyme (500 mL), with stirring, and under nitrogen, maintaining the reaction temperature at 160°-165° C. The cooled reaction mixture was poured into water (1.8 L) and extracted with ether (1.8 L). The organic phase was washed with water, dried over sodium sulfate (Na2SO4), and evaporated. The residue was recrystallized from ethanol, then from acetone/hexane to give 14 g of 1,1-difluoro-1a,10b-dihydrodibenzo[a,e]cyclopropa[c]-cyclohepten-6(1H)-one.

mp 149.6° C.

Flash chromatography of the combined mother liquors on silica gel, eluting with 20% acetone/hexane, gave an additional 6.5 g of the target compound.

Step 2 (1aα,6β,10bα)-1,1-Difluoro-1,1a,6,10b-tetrahydrodibenzo[a,e]cyclopropa[c]cyclohepten-6-ol

Figure US06570016-20030527-C00025

A solution of 1,1-difluoro-1a,10b-dihydro-dibenzo[a,e]cyclopropa[c]cyclohepten-6(1H)-one (20.4 g) in tetrahydrofuran/methanol (1:2, 900 mL) was cooled in an ice bath. Sodium borohydride (12 g) was added in portions. The cooling bath was removed and the reaction mixture was stirred at ambient temperature for 2 hours, then poured into water. The product was filtered off, washed with water, and dried to give 20 g of (1aα,6β,10bα)-1,1-difluoro-1,1a,6,10b-tetrahydrodibenzo[a,e]cyclopropa[c]cyclohepten-6-ol (ii).

mp 230.1°-230.6° C.

Step 2A Combined Steps 1 and 2 Procedure (1aα,6β,10bα)-1,1-Difluoro-1,1a,6,10b-tetrahydrodibenzo[a,e]cyclopropa[c]cyclohepten-6-ol

Figure US06570016-20030527-C00026

To a solution of 103.1 g (0.500 mol) of 5H-dibenzo[a,d]cyclohepten-5-one (2) in 515 mL of triethylene glycol dimethyl ether heated to between 180° C. and 210° C. was added over 7 hours, 293.3 g (2.15 mol) of chlorodifluoroacetic acid lithium salt (as a 53% by weight solution in ethylene glycol dimethyl ether). The ethylene glycol dimethyl ether was allowed to distill from the reaction as the salt addition proceeded. The GC analysis of an aliquot indicated that all of the 5H-dibenzo[a,d]cyclohepten-5-one had been consumed. The reaction was cooled to ambient temperature and then combined with 400 mL of ethyl acetate and 75 g of diatomaceous earth. The solids were removed by filtration and washed with 300 mL of ethyl acetate. The washes and filtrate were combined and the ethyl acetate was removed by concentration under vacuum leaving 635 g of dark liquid. The dark liquid was cooled to 18° C. and to this was added, over 15 minutes, 6.62 g (0.175 mol) of sodium borohydride (as a 12% by wt solution in 14 M NaOH). After stirring for 2 h the reaction was quenched by careful addition of 900 mL of a 1:3.5:4.5 solution of conc. HCl-methanol-water. The suspension was stirred for 30 min and the crude product was collected by filtration, washed with 600 mL of 1:1 methanol-water and dried to 126.4 g of dark brown solid. The crude product was slurried in 600 mL of methylene chloride, filtered, washed twice with 150 mL portions of methylene chloride, and dried to 91.6 g (71%) of (1aα,6β,10bα)-1,1-difluoro-1,1a,6,10b-tetrahydrodibenzo[a,e]cyclopropa[c]-cyclohepten-6-ol. Gas Chromatography (GC) Conditions; Column: JW Scientific DB-1, Initial Temperature 150° C. for 5 min, 10° C./min ramp, Final temp 250° C. for 5 min. tR: intermediate, 11.5 min; reaction product (alcohol), 11.9 min; starting material, 12.3 minutes.

Step 3 Preparation of (1aα,6α,10b)-6-bromo-1,1-difluoro-1,1a,6,10b-tetrahydrodibenzo[a,e]cyclopropa-[c]cycloheptene

Figure US06570016-20030527-C00027

A slurry of (1aα,6β,10bα)-1,1-difluoro-1,1a,6,10b-tetrahydrodibenzo[a,e]cyclopropa[c]-cyclohepten-6-ol (3.0 g, 11.6 mmol, 1.0 equiv) in heptane (24 mL) was treated with 48% HBr (1.58 mL, 14.0 mmol, 1.2 equiv) and the reaction was heated at reflux with vigorous stirring for 2.5 hr. Solvent was then removed by atmospheric distillation (bp 95-98° C.) until approximately 9 mL of distillate was collected. The reaction was cooled and treated with EtOAc (15 mL), Na2SOand activated charcoal. The mixture was stirred at RT for 15 min and filtered through hyflo. The filter cake was washed with 50:50 EtOAc:heptane and the filtrate was concentrated in vacuo to provide the title product as a crystalline solid.

mp 119° C. (3.46 g corr., 93%);

1H NMR (500 MHz CDCl3) δ 7.20-7.41 (8H, m), 5.81 (1H, s), 3.41 (2H, d, J 12.5 Hz);

13CNMR (126 MHz CDCl3) δ 141.3, 141.2, 133.5, 130.1, 129.8, 128.3, 128.2, 112.9, 110.6, 110.5, 108.3, 53.6, 30.2, 30.1, 30.0.

Anal. Calcd. For C16H11BrF2: C, 59.84; H, 3.45. Found: C, 60.13; H, 3.50.

Step 3A Preparation of (1aα,6α,10bα)-6-Bromo-1-difluoro-1,1a,6,10b-tetrahydrodibenzo[a,e]cyclopropa[c]cycloheptene

Figure US06570016-20030527-C00028

To a stirred suspension of (1aα,6β,10bα)-1,1-difluoro-1,1a,6,10b-tetrahydrodibenzo[a,e]cyclopropa[c]-cyclohepten-6-ol, (18.4 g, 71.2 mmol) in 151 mL of methylene chloride which had been cooled to 10-17° C. was added phosphorous tribromide (9.6 g, 35.6 mmol) dropwise over 15 minutes. The cooling bath was removed and the reaction was stirred for 2 hours at ambient temperature. Analysis by gas chromatography indicated complete consumption of starting material. Cold water (92 mL) and activated carbon (1.84 g) were added and the resulting mixture was stirred for 30 minutes. The activated carbon was removed by filtration through Hyflo brand filter aid and the two phases were separated. The organic phase was washed with water (184 mL×2), brine (184 ml), dried over magnesium sulfate and concentrated to dryness under vacuum, affording 21.7 g (94.8%) of (1aα,6α,10bα)-6-bromo-1,1-difluoro-1,1a,6,10b-tetrahydrodibenzo[a,e]cyclopropa[c]cycloheptene.

1H NMR (CDCl3, 300 MHz) δ 3.36 (s, 1H), 3.40 (s, 1H), 5.77 (s, 1H), 7.16-7.38 (m, 8H).

Steps 4 and 5 (1aα,6α,10bα)-1-(1,1-Difluoro-1,1a,6,10b-tetrahydrodibenzo[a,e]cyclopropa[c]cyclohepten-6-yl)-piperazine, Hydrobromide Salt

Figure US06570016-20030527-C00029

To a solution of 237.5 g (0.739 mol) of (1aα,6α,10bα)-6-bromo-1,1-difluoro-1,1a,6,10b-tetrahydrodibenzo[a,e]-cyclopropa[c]cycloheptene in 3.56 L of acetonitrile was added 207.7 g (2.41 mol) of piperazine and the mixture was heated to reflux for 2 hours, at which time analysis by gas chromatography showed complete consumption of (1aα,6α,10bα)-6-bromo-1,1-difluoro-1,1a,6,10b-tetrahydrodibenzo[a,e]cyclopropa[c]cycloheptene (iii) and formation of a mixture of syn and anti piperazine compounds (III and IV) in an anti-syn ratio of 55:45. The reaction was cooled to about 7° C. and stirred for 30 minutes at that temperature. The reaction mixture was filtered to remove the precipitated syn-isomer (III) and the filter cake was washed with 250 mL of acetonitrile. The combined filtrate and wash were concentrated under vacuum to 262.4 grams of a foam which was dissolved in 450 mL of acetonitrile with heating. The solution was cooled to about 12° C. in an ice bath and stirred for 1 hour at that temperature. The precipitated syn-piperazine compound of formula (III) was filtered and washed with 125 ml of acetonitrile. The combined filtrate and wash were concentrated under vacuum to 194.1 g and dissolved in 1.19 L of ethyl acetate. The organic solution was washed sequentially with 500 mL portions of 1N sodium hydroxide, water, and saturated sodium chloride. The ethyl acetate solution was dried over sodium sulfate and concentrated to give 137.0 grams of residue which was dissolved in 1.37 L of methylene chloride and seeded with (1aα,6α,10bα)-1-(1,1-difluoro-1,1a,6,10b-tetrahydrodibenzo[a,e]cyclopropa[c]-cyclohepten-6-yl)-piperazine, hydrobromide salt, followed by the addition of 70.8 grams of 48% aqueous hydrobromic acid. The mixture was stirred for about 45 minutes, causing the anti-isomer to crystallize as its hydrobromide salt. The crystals were filtered, washed with methylene chloride, and dried to provide purified hydrobromide salt of compound (IVa), shown by HPLC to have an anti-syn ratio of 99.3:0.7. Treatment of the isolated hydrobromide salt of compound (IVa) with aqueous sodium hydroxide, extraction into methylene chloride, separation of the aqueous layer and concentration to dryness gave 80.1 grams (33.2% yield based on starting material) of (1aα,6α,10bα)-1-(1,1-difluoro-1,1a,6,10b-tetrahydrodibenzo[a,e]cyclopropa[c]-cyclohepten-6-yl)-piperazine as the free base. Acidification of a solution of the free base in 800 mL of methylene chloride by addition of 41.2 g of 48% hydrobromic acid as described above afforded 96.4 g of pure hydrobromide salt (title compound) with an anti-syn ratio of 99.8:0.2 (HPLC), mp 282-284° C. 1H NMR (DMSO-d6) δ 2.41 (m, 4H), 3.11 (m, 4H), 3.48 (d, J=12.4 Hz, 2H), 4.13 (s, 1H), 7.2 (m, 8H), 8.65 (bs, 2H). 13C NMR (DMSO-d6) δ 28.0, 42.9, 48.0, 75.1, 108.5, 112.9, 117.3, 127.5, 128.0, 128.6, 129.6, 132.4, 141.3. IR: (KBr) 3019, 2481, 1587, 1497, 1298 cm−1. Anal. Calcd for C20H21BrF2N2: C, 58.98; H, 5.20; N, 6.88. Found: C, 58.75; H, 5.29; N, 7.05.

Step 6 Preparation of (2R)-Anti-1-[4-(10,11-difluoromethano-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5-yl)-piperazin-1-yl]-3-quinolin-5-yloxy)propan-2-ol Trihydrochloride

A suspension of (1aα,6α,10bα)-1-(1,1-difluoro-1,1a,6,10b-tetrahydrodibenzo[a,e]cyclopropa[c]-cyclohepten-6-yl)-piperazine, hydrochloride compound of formula IVa (5.41 g, 14.9 mmol) and powdered sodium carbonate (3.16 g, 29.8 mmol) in 54 mL of 3A ethanol was stirred at ambient temperature for 1 hour. R-1-(5-quinolinyloxy)-2,3-epoxypropane (3.00 g, 14.9 mmol) was added in one portion and the reaction mixture was heated to 65° C. for 19 hours. HPLC analysis (Gradient system with solvent A (acetonitrile) and solvent B (0.02M sodium monophosphate buffer containing 0.1% triethylamine adjusted to pH 3.5 with phosphoric acid) as follows: 0-12 min, 30% solvent A/70% solvent B; 12-30 min, linear gradient from 30% to 55% solvent A/70% to 45% solvent B; 30-35 min, 55% solvent A/45% solvent B, 1 mL/min, 1=240 nm, Synchropak SCD-100 25 cm×4.6 mm column) indicated the total consumption of the piperazinyl compound of formula (IV). The mixture was allowed to cool to room temperature, filtered through a plug of silica gel, and eluted with an additional 90 mL of ethanol. The eluent was concentrated to a volume of approximately 60 mL and heated to 65° C. with stirring. A solution of HCl in ethanol (16.1 g at 0.135 g/g of solution, 59.6 mmol) was added dropwise over 10 minutes and the resultant product solution was seeded, causing the trihydrochloride salt to precipitate. The mixture was allowed to cool to ambient temperature and stirred slowly (less than 100 RPM) for 2 hours. The precipitate was filtered, washed with ethanol, and dried in vacuo at 50° C. to give the crude trihydrochloride salt which was further purified by recrystallization from methanol/ethyl acetate to provide 7.45 g (78.4%) of (2R)-anti-1-[4-(10,11-difluoromethano-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5-yl)-piperazin-1-yl]-3-quinolin-5-yloxy)-propan-2-ol trihydrochloride.

Step 6a

The syn isomer compound of formula (III) isolated as described supra (combined steps 4 and 5), can be utilized to produce the corresponding syn-5-{3-[4-(10,11-difluoromethano-dibenzosuber-5-yl)piperazin-1-yl]-2-hydroxypropoxy}quinoline trihydrochloride (XII) essentially as shown below for the free base of the anti isomer (IVa)in step 6.

https://www.google.co.in/patents/US6570016?cl=en

………………………………………

http://www.google.it/patents/WO1994024107A1?cl=en

REACTION SCHEME 1

Figure imgf000012_0001

FormuIa 1

Formula 1

Figure imgf000012_0002

Formula 2 Formula 2

Figure imgf000013_0001

Formula 3

Formula 3

Figure imgf000013_0002

Formula 4

Figure imgf000013_0003

Formula I

……………………………………….

http://www.google.com/patents/WO2000075121A3

Figure US06521755-20030218-C00028

1HNMR (500 MHz DMSO-d6) δ9.41 (2H, br. s), 7.17-7.31 (8H, m), 4.17 (1H, s), 3.52 (2H, d, J=12.4 Hz), 3.11 (4H, br. s), 2.48-2.51 (4H, m)

13CNMR (126 MHz DMSO-d6) δ142.3, 133.4, 130.5, 129.6, 129.0, 128.4, 115.9, 113.6, 111.3, 76.2, 49.0, 43.6, 29.2, 29.1, 29.0; FD MS: m/e 326 (M+).

Anal. Calcd. For C20H21ClF2N2: C, 66.20; H, 5.83; N, 7.72.

Found: C, 66.08; H, 5.90; N, 7.72.

…………………………………………..

http://www.google.com/patents/US6570016?cl=fr

Figure US06570016-20030527-C00019

Figure US06570016-20030527-C00023

(2R)-Anti-1-[4-(10,11-difluoromethano-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5-yl)-piperazin-1-yl]-3-qunolin-5-yloxy)-propan-2-ol Trihydrochloride

……………….

Chemical Shift Data and Peak Assignments for the Crystal Forms.

https://www.google.co.in/patents/US7282585?pg=PA1&dq=US+7282585&hl=en&sa=X&ei=zN64UsC2FIaSrgfS8YGIBQ&ved=0CDcQ6AEwAA

Figure US07282585-20071016-C00001

Form II has a solid-state 13C NMR spectrum comprised of isotropic peaks at the following chemical shifts: 29.9, 50.1, 55.3, 62.0, 66.5, 72.0, 75.8, 104.8, 107.5, 108.2, 109.1, 110.2, 112.0, 118.4, 119.5, 120.1, 123.1, 128.7, 131.1, 133.0, 134.8, 136.4, 136.9, 139.9, 140.0, 142.3, 144.5, 146.6, 149.0, 144.2, 153.0 and 153.6 ppm.

Form III has a solid-state 13C NMR spectrum comprised of isotropic peaks at the following chemical shifts: 30.3, 50.4, 59.1, 63.2, 72.8, 77.2, 109.1, 110.2, 112.2, 112.8, 118.7, 119.5, 119.9, 121.0, 122.2, 123.0, 128.9, 130.6, 132.7, 134.0, 136.4, 140.0, 141.0, 141.8, 142.5, 143.3, 146.1, 153.1, 153.8 and 154.7 ppm.

World Drug Tracker: Daclatasvir


World Drug Tracker: Daclatasvir

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

DACLATASVIR

Daclatasvir

BMS-790052, 
EBP 883; BMS 790052
cas no 1009119-64-5
THERAPEUTIC CLAIM Treatment of hepatitis C
CHEMICAL NAMES
1. Carbamic acid, N,N’-[[1,1′-biphenyl]-4,4′-diylbis[1H-imidazole-5,2-diyl-(2S)-2,1-
 pyrrolidinediyl[(1S)-1-(1-methylethyl)-2-oxo-2,1-ethanediyl]]]bis-, C,C’-dimethyl ester
2. dimethyl N,N’-(biphenyl-4,4′-diylbis{1H-imidazole-5,2-diyl-[(2S)-pyrrolidine-2,1-
 diyl][(1S)-1-(1-methylethyl)-2-oxoethane-2,1-diyl]})dicarbamate
MOLECULAR FORMULA C40H50N8O6
MOLECULAR WEIGHT 738.9
SPONSOR Bristol-Myers Squibb
CODE DESIGNATION BMS-790052
CAS REGISTRY NUMBER 1009119-64-5
nmr
Daclatasvir dihydrochloride
THERAPEUTIC CLAIM Treatment of hepatitis C
CHEMICAL NAMES
1. Carbamic acid, N,N’-[[1,1′-biphenyl]-4,4′-diylbis[1H-imidazole-5,2-diyl-(2S)-2,1-
 pyrrolidinediyl[(1S)-1-(1-methylethyl)-2-oxo-2,1-ethanediyl]]]bis-, C,C’-dimethyl ester,
 hydrochloride (1:2)
2. dimethyl N,N’-(biphenyl-4,4′-diylbis{1H-imidazole-5,2-diyl-[(2S)-pyrrolidine-2,1-
 diyl][(1S)-1-(1-methylethyl)-2-oxoethane-2,1-diyl]})dicarbamate dihydrochloride
MOLECULAR FORMULA C40H50N8O6 . 2 HCl
MOLECULAR WEIGHT 811.8
SPONSOR Bristol-Myers Squibb
CODE DESIGNATION BMS-790052-05
CAS REGISTRY NUMBER 1009119-65-6
Hepatitis C virus (HCV) is a major global health problem, with an estimated 150-200 million people infected worldwide, including at least 5 million in Europe (Pawlotsky, Trends Microbiol, 2004, 12: 96-102). According to the World Health Organization, 3 to 4 million new infections occur each year. The infection is often asymptomatic; however, the majority of HCV-infected individuals develop chronic infection (Hoof agle, Hepatology, 2002, 36: S21-S29; Lauer et al, N. Engl. J. Med., 2001, 345: 41-52; Seeff, Semin. Gastrointest., 1995, 6: 20-27). Chronic infection frequently results in serious liver disease, including fibrosis and steatosis (Chisari, Nature, 2005, 435: 930-932). About 20% of patients with chronic HCV infection develop liver cirrhosis, which progresses to hepatocellular carcinoma in 5% of the cases (Hoofnagle, Hepatology, 2002, 36: S21-S29; Blonski et al, Clin. Liver Dis., 2008, 12: 661-674; Jacobson et al, Clin. Gastroenterol. Hepatol, 2010, 8: 924-933; Castello et al., Clin. Immunol, 2010, 134: 237-250; McGivern et al., Oncogene, 2011, 30: 1969-1983).
Chronic HCV infection is the leading indication for liver transplantations (Seeff et al., Hepatology, 2002, 36: 1-2). Unfortunately, liver transplantation is not a cure for hepatitis C; viral recurrence being an invariable problem and the leading cause of graft loss (Brown, Nature, 2005, 436: 973-978; Watt et al, Am. J. Transplant, 2009, 9: 1707-1713). No vaccine protecting against HCV is yet available. Current therapies include administration of ribavirin and/or interferon-alpha (IFN-Cc), two non-specific anti-viral agents. Using a combination treatment of pegylated IFN-CC and ribavirin, persistent clearance is achieved in about 50% of patients with genotype 1 chronic hepatitis C. However, a large number of patients have contraindications to one of the components of the combination; cannot tolerate the treatment; do not respond to interferon therapy at all; or experience a relapse when administration is stopped. In addition to limited efficacy and substantial side effects such as neutropenia, haemo lytic anemia and severe depression, current antiviral therapies are also characterized by high cost. To improve efficacy of standard of care (SOC), a large number of direct acting antivirals (DAAs) targeting viral polyprotein processing and replication have been developed (Hofmann et al, Nat. Rev; Gastroenterol. Hepatol., 2011, 8: 257-264). These include small molecule compounds targeting HCV nonstructural proteins including the HCV protease, polymerase and NS5A protein. Although a marked improvement of antiviral response was observed when protease inhibitors were combined with SOC (Hofmann et al, Nat. Rev; Gastroenterol. Hepatol, 2011, 8: 257-264; Bacon et al, New Engl. J. Med., 2011, 364: 1207-1217; McHutchison et al, New Engl. J. Med., 2010, 362: 1292-1303; Poordad et al, New Engl. J. Med., 201 1, 364: 1195-1206; Hezode et al, New Engl. J. Med., 2009, 360: 1839-1850; Kwo et al, Lancet, 2010, 376: 705-716), toxicity of the individual compounds and rapid development of viral resistance in a substantial fraction of patients remain major challenges (Pawlotsky, Hepatology, 2011, 53: 1742-1751; Pereira et al, Nat. Rev. Gastroenterol. Hepatol., 2009, 6: 403-411; Sarrazin et al, Gastroenterol., 2010, 138: 447-462). New therapeutic approaches against HCV are therefore still needed. HCV entry into target cells is a promising target for antiviral preventive and therapeutic strategies since it is essential for initiation, spread, and maintenance of infection (Timpe et al, Gut, 2008, 57: 1728-1737; Zeisel et al, Hepatology, 2008, 48: 299-307). Indeed, HCV initiates infection by attaching to molecules or receptors on the surface of hepatocytes. Current evidence suggests that HCV entry is a multistep process involving several host factors including heparan sulfate (Barth et al, J. Biol. Chem., 2003, 278: 41003-41012), the tetraspanin CD81 (Pileri et al, Science, 1998, 282: 938-941), the scavenger receptor class B type I (SR-BI) (Zeisel et al, Hepatology, 2007, 46: 1722-1731; Bartosch et al, J. Exp. Med., 2003, 197: 633-642; Grove et al, J. Virol, 2007, 81 : 3162-3169; Kapadia et al, J. Virol, 2007, 81 : 374- 383; Scarselli et al, EMBO J., 2002, 21 : 5017-5025), Occludin (Ploss et al, Nature, 2009, 457: 882-886) and Claudin-1 (CLDN1), an integral membrane protein and a component of tight-junction strands (Evans et al, Nature, 2007, 446: 801-805). Furthermore, Niemann-Pick CI -like cholesterol absorption receptor has been identified as a new hepatitis C virus entry factor (Sainz et al, Nature Medicine, 2012, 18: 281-285).
Daclatasvir (USAN[1]) (formerly BMS-790052) is an experimental drug candidate for the treatment of hepatitis C. It is being developed by Bristol-Myers Squibb.
Daclatasvir’s mechanism of action involves inhibition of the HCV nonstructural protein NS5A.[2][3] Recent research suggests that it targets two steps of the viral replication process, enabling rapid decline of HCV RNA.[4]
Daclatasvir has been tested in combination regimens with pegylated interferon and ribavirin,[5] as well as with other direct-acting antiviral agents including asunaprevir[6][7][8][9] and sofosbuvir.[10]
Daclatasvir (BMS-790052; EBP 883) is a first-in-class, highly-selective oral HCV NS5A inhibitor. NS5A is an essential component for hepatitis C virus (HCV) replication complex.Daclatasvir (BMS-790052; EBP 883)has broad genotype coverage and exhibits picomolar in vitro potency against genotypes 1a (EC50 50pm) and 1b (EC50 9pm).Daclatasvir (BMS-790052; EBP 883) produces a robust decline in HCV RNA (-3.6 logs after 48 hours from a single 100 mg) dosefollowing a single dose in patients chronically infected with HCV genotype 1.
It may be many years before the symptoms of hepatitis C infection appear. However, once they do, the consequences are significant: patients may have developed fibrosis, cirrhosis or even liver cancer, with the end result being liver failure. Even if diagnosed early, there’s no guarantee of a cure. Only around half of patients respond to the standard therapy of an interferon plus the antiviral drug ribavirin, and while two add-on antiviral therapies were approved in 2011, the treatment period is long with no guarantee of a cure, and for non-responders treatment options remain limited.
A new drug with a different mechanism is being developed by Bristol-Myers Squibb, in conjunction with Pharmasset. Daclatasvir targets non-structural protein 5A, which is an important component of the viral replication process, although its precise role in this remains unclear. The drug is active in single oral doses, and may have potential as part of a treatment regimen that avoids the use of interferon, and in patients who do not respond to standard therapy.
In an open label Phase IIa study, 10 patients with chronic hepatitis C genotype 1b infection who did not respond to standard therapy were given daclatasvir in once daily 60mg doses, plus another experimental drug, BMS-790052, which is an NSP 3 protease inhibitor, in initial twice-daily 600mg doses, later reduced to 200mg twice a day.2 Nine patients completed 24 weeks of treatment, with the 10th discontinuing after 10 weeks. In those who completed the course, HCV RNA was undetectable at week 8, and remained so until the end of the trial, with all achieving a sustained virologic response. It was also undetectable post-treatment in the patient who discontinued.
Daclatasvir has also been investigated as monotherapy in a double blind, placebo-controlled, sequential panel, multiple ascending dose study.3 Thirty patients with chronic geno-type 1 hepatitis C infection were randomised to receive a 14 day course of the drug, in once daily doses of 1, 10, 30, 60 or 100mg, 30mg twice a day, or placebo. There was no evidence of antiviral activity in the placebo group, but the mean maximum decline of 2.8 to 4.1 log IU/ml. Most experienced viral rebound on or before day 7 of treatment, which was associated with viral variants that had previously been implicated in resistance development. It was well tolerated in all dose groups.
 M. Gao et al. Nature 2010, 465, 96
22/11/2013

EUROPEAN MEDICINES AGENCY ADVISES ON COMPASSIONATE USE OF DACLATASVIR

Opinion concerns use in combination with sofosbuvir in patients with chronic hepatitis C in urgent need of therapy to prevent progression of liver disease
The European Medicines Agency’s Committee for Medicinal Products for Human Use(CHMP) has given an opinion on the use of daclatasvir in combination with sofosbuvir in the treatment of chronic (long-term) hepatitis C virus (HCV) infection, in a compassionate-use programme.
Compassionate-use programmes are set up at the level of individual Member States. They are intended to give patients with a life-threatening, long-lasting or seriously disabling disease with no available treatment options access to treatments that are still under development and that have not yet received amarketing authorisation. In this specific case, Sweden has requested an opinion from the CHMP on the conditions under which early access through compassionate use could be given to daclatasvir, for the use in combination with sofosbuvir, with or without ribavirin, for a specific patient population.
The recommended compassionate use is intended for adult patients at a high risk of their liver being no longer able to function normally (decompensation) or death within 12 months if left untreated, and who have a genotype 1 infection. Further, it is recognised that the potential benefit of such combination therapy may extend to patients infected with other HCV genotypes.
Daclatasvir and sofosbuvir are both first-in-class anti-viral medicines against HCV. These medicines have been studied in combination, with or without ribavirin, in aclinical trial which included treatment-naive (previously untreated) HCV genotype-1, -2 and -3 infected patients, as well as patients with genotype 1 infection who have previously failed telaprevir or boceprevir treatment. Results from the trial indicate high efficacy, also in those who have failed treatment with these protease inhibitors. Many such patients have very advanced liver disease and are in urgent need of effective therapy in order to cease the progression of liver injury.
This is the second opinion provided by the CHMP on compassionate use of medicines in development for the treatment of hepatitis C. Overall, it isthe fourth time compassionate use has been assessed by the CHMP.
The aim of the CHMP assessment and opinion on a compassionate-use programme for new medicinal products is to ensure a common approach, whenever possible, regarding the criteria and conditions of use under Member States’ legislation. The opinion provides recommendations to the EU Member States that are considering setting up such a programme, and its implementation is not mandatory. In addition to describing which patients may benefit from the medicine, it explains how to use it and gives information on safety.
The assessment report and conditions of use of daclatasvir in combination with sofosbuvir with or without ribavirin in this setting will be published shortly on the Agency’s website.
Notes
  • The first compassionate-use opinion for a hepatitis C treatment was adopted by the CHMP in October 2013.
  • Sofosbuvir, which is part of this compassionate-use opinion, received a positive opinion from the CHMP recommending granting of a marketing authorisation at its November 2013 meeting.
  • Daclatasvir is developed by Bristol-Myers Squibb and sofosbuvir is developed by Gilead.

REFERENCES

  1. Jump up^ Statement on a Nonproprietary Name Adopted by the USAN Council
  2. Jump up^ Gao, Min; Nettles, Richard E.; Belema, Makonen; Snyder, Lawrence B.; Nguyen, Van N.; Fridell, Robert A.; Serrano-Wu, Michael H.; Langley, David R.; Sun, Jin-Hua; O’Boyle, Donald R., II; Lemm, Julie A.; Wang, Chunfu; Knipe, Jay O.; Chien, Caly; Colonno, Richard J.; Grasela, Dennis M.; Meanwell, Nicholas A.; Hamann, Lawrence G. (2010). “Chemical genetics strategy identifies an HCV NS5A inhibitor with a potent clinical effect”. Nature 465(7294): 96–100. doi:10.1038/nature08960PMID 20410884.
  3. Jump up^ Bell, Thomas W. (2010). “Drugs for hepatitis C: unlocking a new mechanism of action“. ChemMedChem 5 (10): 1663–1665.doi:10.1002/cmdc.201000334PMID 20821796.
  4. Jump up^ Modeling shows that the NS5A inhibitor daclatasvir has two modes of action and yields a shorter estimate of the hepatitis C virus half-life. Guedj, J et al. Proceedings of the National Academy of Sciences. February 19, 2013.
  5. Jump up^ AASLD: Daclatasvir with Pegylated Interferon/Ribavirin Produces High Rates of HCV Suppression. Highleyman, L. HIVandHepatitis.com. 6 December 2011.
  6. Jump up^ Preliminary Study of Two Antiviral Agents for Hepatitis C Genotype 1. Lok, A et al. New England Journal of Medicine. 366(3):216-224. January 19, 2012.
  7. Jump up^ “Bristol-Myers’ Daclatasvir, Asunaprevir Cured 77%: Study”Bloomberg. Apr 19, 2012.
  8. Jump up^ AASLD: Daclatasvir plus Asunaprevir Rapidly Suppresses HCV in Prior Null Responders. Highleyman, L. HIVandHepatitis.com. 8 November 2011.
  9. Jump up^ High rate of response to BMS HCV drugs in harder-to-treat patients – but interferon-free prospects differ by sub-genotype. Alcorn, K. Aidsmap.com. 12 November 2012.
  10. Jump up^ AASLD 2012: Sofosbuvir + Daclatasvir Dual Regimen Cures Most Patients with HCV Genotypes 1, 2, or 3. Highleyman, L. HIVandHepatitis.com. 15 November 2012.
1-6-2012
Anti-Viral Compounds
2-13-2009
CRYSTALLINE FORM OF METHYL ((1S)-1-(((2S)
-2-(5-(4′-(2-((2S)-1((2S)-2-((METHOXYCARBONYL)AMINO)-3-METHYLBUTANOYL)-2-PYRROLIDINYL)
-1H-IMIDAZOL-5-YL)-4-BIPHENYLYL)-1H-IMIDAZOL-2-YL)-1-PYRROLIDINYL)CARBONYL)
-2-METHYLPROPYL)CARBAMATE DIHYDROCHLORIDE SALT

synthesis

  • https://www.google.co.in/patents/US20090041716?pg=PA1&dq=us+2009041716&hl=en&sa=X&ei=3ki4Uo-jEsTirAfzwoHQBQ&ved=0CD4Q6AEwAQ
  • EXAMPLES
    Figure US20090041716A1-20090212-C00015
    A 1 L, 3-neck round bottom flask, fitted with a nitrogen line, overhead stirrer and thermocouple, was charged with 20 g (83.9 mmol, 1 equiv) 1,1′-(biphenyl-4,4′-diyl)diethanone, 200 mL CH2Cland 8.7 mL (27.1 g, 169.3 mmol, 2.02 quiv) bromine. The mixture was allowed to stir under nitrogen for about 20 hours under ambient conditions. The resulting slurry was charged with 200 mL CH2Cland concentrated down to about 150 mL via vacuum distillation. The slurry was then solvent exchanged into THF to a target volume of 200 mL via vacuum distillation. The slurry was cooled to 20-25° C. over 1 hour and allowed to stir at 20-25° C. for an additional hour. The off-white crystalline solids were filtered and washed with 150 mL CH2Cl2. The product was dried under vacuum at 60° C. to yield 27.4 g (69.2 mmol, 82%) of the desired product: 1H NMR (400 MHz, CDCl3) δ 7.95-7.85 (m, 4H), 7.60-7.50 (m, 4H), 4.26 (s, 4H); 13C NMR (100 MHz, CDCl3) 6 191.0, 145.1, 133.8, 129.9, 127.9, 30.8; IR (KBr, cm−1) 3007, 2950, 1691, 1599, 1199; Anal calcd for C16H12Br2O2: C, 48.52; H, 3.05; Br, 40.34. Found: C, 48.53; H, 3.03; Br, 40.53 HRMS calcd for C16H13Br2O(M+H; DCI+): 394.9282. Found: 394.9292. mp 224-226° C.
    Figure US20090041716A1-20090212-C00016
    A 500 mL jacketed flask, fitted with a nitrogen line, thermocouple and overhead stirrer, was charged with 20 g (50.5 mmol, 1 equiv) of Compound 2, 22.8 g (105.9 moles, 2.10 equiv) 1-(tert-butoxycarbonyl)-L-proline and 200 mL acetonitrile. The slurry was cooled to 20° C. followed by the addition of 18.2 mL (13.5 g, 104.4 mmol, 2.07 equiv) DIPEA. The slurry was warmed to 25° C. and allowed to stir for 3 hours. The resulting clear, organic solution was washed with 3×100 mL 13 wt % aqueous NaCl. The rich acetonitrile solution was solvent exchanged into toluene (target volume=215 mL) by vacuum distillation until there was less than 0.5 vol % acetonitrile.
    Figure US20090041716A1-20090212-C00017
    The toluene solution of Compound 3 was charged with 78 g (1.011 moles, 20 equiv) ammonium acetate and heated to 95-100° C. The mixture was allowed to stir at 95-100° C. for 15 hours. After reaction completion, the mixture was cooled to 70-80° C. and charged with 7 mL acetic acid, 40 mL n-butanol, and 80 mL of 5 vol % aqueous acetic acid. The resulting biphasic solution was split while maintaining a temperature >50° C. The rich organic phase was charged with 80 mL of 5 vol % aqueous acetic acid, 30 mL acetic acid and 20 mL n-butanol while maintaining a temperature >50° C. The resulting biphasic solution was split while maintaining a temperature >50° C. and the rich organic phase was washed with an additional 80 mL of 5 vol % aqueous acetic acid. The rich organic phase was then solvent exchanged into toluene to a target volume of 215 mL by vacuum distillation. While maintaining a temperature >60° C., 64 mL methanol was charged. The resulting slurry was heated to 70-75° C. and aged for 1 hour. The slurry was cooled to 20-25° C. over 1 hour and aged at that temperature for an additional hour. The slurry was filtered and the cake was washed with 200 mL 10:3 toluene:methanol. The product was dried under vacuum at 70° C., resulting in 19.8 g (31.7 mmol, 63%) of the desired product: 1H NMR (400 MHz, DMSO-d6) δ 13.00-11.00 (s, 2H), 7.90-7.75 (m, 4H), 7.75-7.60 (m, 4H), 7.60-7.30 (s, 2H), 4.92-4.72 (m, 2H), 3.65-3.49 (m, 2H), 3.49-3.28 (m, 2H), 2.39-2.1 (m, 2H), 2.10-1.87 (m, 6H), 1.60-1.33 (s, 8H), 1.33-1.07 (s, 10H); 13C NMR (100 MHz, DMSO-d6) δ 154.1, 153.8, 137.5, 126.6, 125.0, 78.9, 78.5, 55.6, 55.0, 47.0, 46.7, 33.7, 32.2, 28.5, 28.2, 24.2, 23.5; IR (KBr, cm−1) 2975, 2876, 1663, 1407, 1156, 1125; HRMS calcd for C36H45N6O(M+H; ESI+): 625.3502. Found: 625.3502. mp 190-195° C. (decomposed).
    Figure US20090041716A1-20090212-C00018
    To a 250 mL reactor equipped with a nitrogen line and overhead stirrer, 25.0 g of Compound 4 (40.01 mmol, 1 equiv) was charged followed by 250 mL methanol and 32.85 mL (400.1 mmol, 10 equiv) 6M aqueous HCl. The temperature was increased to 50° C. and agitated at 50° C. for 5 hours. The resulting slurry was cooled to 20-25° C. and held with agitation for about 18 hours. Filtration of the slurry afforded a solid which was washed successively with 100 mL 90% methanol/water (V/V) and 2×100 mL of methanol. The wet cake was dried in a vacuum oven at 50° C. overnight to give 18.12 g (31.8 mmol, 79.4%) of the desired product.

    Recrystallization of Compound 5

    To a 250 mL reactor equipped with a nitrogen line and an overhead stirrer, 17.8 g of Compound 5 from above was charged followed by 72 mL methanol. The resulting slurry was agitated at 50° C. for 4 hours, cooled to 20-25° C. and held with agitation at 20-25° C. for 1 hour. Filtration of the slurry afforded a crystalline solid which was washed with 60 mL methanol. The resulting wet cake was dried in a vacuum oven at 50° C. for 4 days to yield 14.7 g (25.7 mmol, 82.6%) of the purified product: 1H NMR (400 MHz, DMSO-d6) δ 10.5-10.25 (br, 2H), 10.1-9.75 (br, 2H), 8.19 (s, 2H), 7.05 (d, J=8.4, 4H), 7.92 (d, J=8.5, 4H), 5.06 (m, 2H), 3.5-3.35 (m, 4H), 2.6-2.3 (m, 4H), 2.25-2.15 (m, 2H), 2.18-1.96 (m, 2H); 13C NMR (100 MHz, DMSO-d6) δ 156.6, 142.5, 139.3, 128.1, 127.5, 126.1, 116.9, 53.2, 45.8, 29.8, 24.3; IR (KBr, cm−1) 3429, 2627, 1636, 1567, 1493, 1428, 1028. Anal calcd for C26H32N6Cl4: C, 54.75; H, 5.65; Cl, 24.86; Adjusted for 1.9% water: C, 53.71; H, 5.76; N, 14.46; Cl, 24.39. Found: C, 53.74; H, 5.72; N, 14.50; Cl, 24.49; KF=1.9. mp 240° C. (decomposed).
    Figure US20090041716A1-20090212-C00019
    A 1 L jacketed flask equipped with a nitrogen line and an overhead stirrer was sequentially charged with 100 mL acetonitrile, 13.69 g (89.4 mmol, 2.5 equiv) hydroxybenzotriazole hydrate, 15.07 g (86 mmol, 2.4 equiv) N-(methoxycarbonyl)-L-valine, 16.46 g (85.9 mmol, 2.4 equiv) 1-(3-dimethyaminopropyl)-3-ethylcarbodiimide hydrochloride and an additional 100 mL acetonitrile. The resulting solution was agitated at 20° C. for 1 hour and charged with 20.4 g (35.8 mmol, 1 equiv) of purified Compound 5. The slurry was cooled to about 0° C. and 18.47 g (142.9 mmol, 4 equiv) diisopropylethylamine was added over 30 minutes while maintaining a temperature below 10° C. The solution was slowly heated to 15° C. over 3 hours and held at 15° C. for 12 hours. The resulting solution was charged with 120 mL 13 wt % aqueous NaCl and heated to 50° C. for 1 hour. After cooling to 20° C., 100 mL of isopropyl acetate was added. The biphasic solution was filtered through a 0.45 μm filter and the mixture split. The rich organic phase was washed with 2×240 mL of a 0.5 N NaOH solution containing 13 wt % NaCl followed by 120 mL 13 wt % aqueous NaCl. The mixture was then solvent exchanged into isopropyl acetate by vacuum distillation with a target volume of 400 mL. The resulting hazy solution was cooled to 20° C. and filtered through a 0.45 μm filter. The clear solution was then solvent exchanged into ethanol by vacuum distillation with a target volume of 140 mL. While maintaining a temperature of 50° C., 66.4 mL (82.3 mmol, 2.3 equiv) of 1.24M HCl in ethanol was added. The mixture was then charged with 33 mg (0.04 mmol, 0.001 equiv) of seed crystals of Compound (I) (see preparation below) and the resulting slurry was stirred at 50° C. for 3 hours. The mixture was cooled to 20° C. over 1 hour and aged at that temperature for an additional 22 hours. The slurry was filtered and the wet cake was washed with 100 mL of 2:1 acetone:ethanol. The solids were dried in a vacuum oven at 70° C. to give 22.15 g (27.3 mmol, 76.3%) of the desired product.
    Figure US20090041716A1-20090212-C00020
    A solution of Compound (I) was prepared by dissolving 3.17 g of Compound (I) from above in 22 mL methanol. The solution was passed through a 47 mm Cuno Zeta Carbon® 53SP filter at ˜5 psig at a flow rate of ˜58 mL/min. The carbon filter was rinsed with 32 mL of methanol. The solution was concentrated down to 16 mL by vacuum distillation. While maintaining a temperature of 40-50° C., 15.9 mL acetone and 5 mg of seed crystals of Compound (I) (see procedure below) were added. The resulting slurry was then charged with 32 mL acetone over 30 minutes. The slurry was held at 50° C. for 2 hours, cooled to 20° C. over about 1 hour and held at 20° C. for about 20 hours. The solids were filtered, washed with 16 mL 2:1 acetone:methanol and dried in a vacuum oven at 60° C. to give 2.14 g (67.5%) of purified Compound (I): 1H NMR (400 MHz, DMSO-d6, 80° C.): 8.02 (d, J=8.34 Hz, 4 H), 7.97 (s, 2 H), 7.86 (d, J=8.34 Hz, 4 H), 6.75 (s, 2 H), 5.27 (t, J=6.44 Hz, 2 H), 4.17 (t, J=6.95 Hz, 2 H), 3.97-4.11 (m, 2 H), 3.74-3.90 (m, 2 H), 3.57 (s, 6 H), 2.32-2.46 (m, 2 H), 2.09-2.31 (m, 6 H), 1.91-2.07 (m, 2 H), 0.88 (d, J=6.57 Hz, 6 H), 0.79 (d, J=6.32 Hz, 6 H); 13C NMR (75 MHz, DMSO-d6): δ 170.9, 156.9, 149.3, 139.1, 131.7, 127.1, 126.5, 125.9, 115.0, 57.9, 52.8, 51.5, 47.2, 31.1, 28.9, 24.9, 19.6, 17.7; IR (neat, cm−1): 3385, 2971, 2873, 2669, 1731, 1650. Anal. Calcd for C40H52N8O6Cl2: C, 59.18; H, 6.45; N, 13.80; Cl, 8.73. Found C, 59.98; H, 6.80; N, 13.68; Cl, 8.77. mp 267° C. (decomposed).
  • Figure US20090041716A1-20090212-C00014
  • https://www.google.co.in/patents/US20090041716?pg=PA1&dq=us+2009041716&hl=en&sa=X&ei=3ki4Uo-jEsTirAfzwoHQBQ&ved=0CD4Q6AEwAQ

Compound 1(

Figure imgb0001

) or a pharmaceutically acceptable salt thereof. Compound 1 is also known as (2R,6S,13aS,14aR,16aS,Z)-N-(cyclopropylsulfonyl)-6-(5-methylpyrazine-2-carboxamido)-5,16-dioxo-2-(phenanthridin-6-yloxy)-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. Compound 1 is a potent HCV protease inhibitor. The synthesis and formulation of Compound 1 are described in U.S. Patent Application Publication No. 2010/0144608 , U.S. Provisional Application Serial No. 61/339,964 filed on March 10, 2010 , andU.S. Patent Application Publication No. 2011/0312973 filed on March 8, 2011 

Table 1 belows lists additional suitable Hepatitis C therapeutic agents that may be used in combination
Table 1
Figure imgf000013_0001
Figure imgf000014_0001
ALS-2158 Vertex Nl I n/a
Figure imgf000015_0001
Figure imgf000016_0001
…………………………..

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