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DR ANTHONY MELVIN CRASTO Ph.D

DR ANTHONY MELVIN CRASTO Ph.D

DR ANTHONY MELVIN CRASTO, Born in Mumbai in 1964 and graduated from Mumbai University, Completed his Ph.D from ICT, 1991,Matunga, Mumbai, India, in Organic Chemistry, The thesis topic was Synthesis of Novel Pyrethroid Analogues, Currently he is working with GLENMARK PHARMACEUTICALS LTD, Research Centre as Principal Scientist, Process Research (bulk actives) at Mahape, Navi Mumbai, India. Total Industry exp 30 plus yrs, Prior to joining Glenmark, he has worked with major multinationals like Hoechst Marion Roussel, now Sanofi, Searle India Ltd, now RPG lifesciences, etc. He has worked with notable scientists like Dr K Nagarajan, Dr Ralph Stapel, Prof S Seshadri, Dr T.V. Radhakrishnan and Dr B. K. Kulkarni, etc, He did custom synthesis for major multinationals in his career like BASF, Novartis, Sanofi, etc., He has worked in Discovery, Natural products, Bulk drugs, Generics, Intermediates, Fine chemicals, Neutraceuticals, GMP, Scaleups, etc, he is now helping millions, has 9 million plus hits on Google on all Organic chemistry websites. His friends call him Open superstar worlddrugtracker. His New Drug Approvals, Green Chemistry International, All about drugs, Eurekamoments, Organic spectroscopy international, etc in organic chemistry are some most read blogs He has hands on experience in initiation and developing novel routes for drug molecules and implementation them on commercial scale over a 30 year tenure till date Dec 2017, Around 35 plus products in his career. He has good knowledge of IPM, GMP, Regulatory aspects, he has several International patents published worldwide . He has good proficiency in Technology transfer, Spectroscopy, Stereochemistry, Synthesis, Polymorphism etc., He suffered a paralytic stroke/ Acute Transverse mylitis in Dec 2007 and is 90 %Paralysed, He is bound to a wheelchair, this seems to have injected feul in him to help chemists all around the world, he is more active than before and is pushing boundaries, He has 9 million plus hits on Google, 2.5 lakh plus connections on all networking sites, 50 Lakh plus views on dozen plus blogs, He makes himself available to all, contact him on +91 9323115463, email amcrasto@gmail.com, Twitter, @amcrasto , He lives and will die for his family, 90% paralysis cannot kill his soul., Notably he has 19 lakh plus views on New Drug Approvals Blog in 216 countries......https://newdrugapprovals.wordpress.com/ , He appreciates the help he gets from one and all, Friends, Family, Glenmark, Readers, Wellwishers, Doctors, Drug authorities, His Contacts, Physiotherapist, etc

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WO 2018066004, NEW PATENT, INDOCO REMEDIES LIMITED, DORZOLAMIDE


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 (WO2018066004) PROCESS FOR THE PREPARATION OF DORAOLZMIDE HYDROCHLORIDE

https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2018066004&redirectedID=true

Applicants: INDOCO REMEDIES LIMITED [IN/IN]; Indoco House, 166 C.S.T. Road, Santacruz (East) Mumbai, Maharashtra 400098 (IN)
Inventors: SHETH, Nilima; (IN).
KUDUVA, Srinivasan Subramanian; (IN).
RAMESAN, Palangat Vayalileveetil; (IN).
PANANDIKAR, Aditi Milind; (IN)

nilima sheth

SHETH, Nilima

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Aditi Kare Panandikar, Managing Director, Indoco Remedies

Process for preparing dorzolamide hydrochloride is claimed. It is disclosed that dorzolamide hydrochloride is a carbonic anhydrase inhibitor. 

Trusopt is an ophthalmic solution containing the carbonic anhydrase inhibitor dorzolamide hydrochloride for treating intraocular pressure in patients with ocular hypertension or open-angle glaucoma, which was developed and launched by Merck & Co , and is also now marketed by Santen Pharmaceuticals and Mundipharma International . 

In April 2018, Newport Premium™ reported that Indoco Remedies was capable of producing commercial quantities of dorzolamide hydrochloride and holds an active US DMF since 2010

Dorzolamide hydrochloride is a carbonic anhydrase (CA) inhibitor. It is chemically represented by (4S,6S)-4-(ethylamino)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide hydrochloride; and is structurally represented

Formula I

It acts as an anti -glaucoma agent, in open-angle glaucoma and ocular hypertension. It is used in ophthalmic solutions to lower intraocular pressure (IOP).

The compound dorzolamide hydrochloride has been in the market for very long time. It is administered as a topical ophthalmic in the form of a solution and marketed under the brand name T rusopt.

Dorzolamide hydrochloride and process for its preparation are first described in the patent, US 4,797,413 (US 413 Patent) and its corresponding European patent, E P 0296879. The process described in US 413 patent involves reacting thiophene-2-thiol with but-2-enoic acid and further proceeds with formation of racemic 4- ( ethyl ami no) – 6- methyl -5, 6- di hydro-4H -thi eno[2, 3- b] thi opy ran-2-sul f onami de 7, 7-di oxide (dorzolamide base).

A number of further processes for the preparation of dorzolamide hydrochloride have been devised and in many of these, as well as in the above US 413 Patent, the last step of the process involves the removal of diastereomeric impurity from the racemic mixture of dorzolamide base. To obtain pure dorzolamide hydrochloride devoid of the diastereomeric impurity of cis-isomer from the racemic compound, as per the patent US ~413, racemic mixture of dorzolamide base is subjected to column chromatography and then resolution is carried out using resolving agent di-p-tol uoyl-L -tartaric acid monohydrate in n-propanol. The salt formed is treated with base to get dorzolamide free base, which is reacted with ethanolic hydrochloric acid to get dorzolamide hydrochloride. The compound is further recrystallised from mixture of solvents viz., methanol and isopropanol to get pure dorzolamide hydrochloride.

US 5,688,968 describes a process for preparation of dorzolamide hydrochloride, wherein chiral hydroxyl sulfone compound having fixed chirality, proceeds via Ritter reaction to obtain dorzolamide base having mixture of cis- and trans-isomer. The compound dorzolamide base is reacted with maleic acid to isolate maleate salt of dorzolamide. The salt is again converted to free base and then reacted with hydrochloric acid in ethyl acetate to get required pure trans-isomer of dorzolamide hydrochloride.

The PCT patent publication W 02006038222 discloses the preparation of dorzolamide hydrochloride, wherein the cis- and trans-isomer of racemic dorzolamide base is separated using resolution via chiral salt formation with di benzoyl -L -tartaric acid monohydrate or di-p-tol uoyl-L -tartaric acid monohydrate in methanol which on neutralization results in dorzolamide base. The base is then reacted with hydrochloric acid in isopropanol to give

dorzol amide hydrochloride which is recrystalised in isopropanol to obtain pure dorzol amide hydrochloride.

Another US patent US 7,109,353 discloses the process for preparation of dorzolamide hydrochloride, wherein racemic 4-(ethylamino)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide is treated with mineral acid to form the corresponding salt, which is then converted to racemic trans-4-(ethylamino)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide and resolved with di-p-toluoyl-D -tartaric acid followed by neutralization of the chiral salt to isolate trans-(4S,6S)-4-(ethylamino)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide. The compound trans-(4S,6S)-4-(ethylamino)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide on reaction with hydrochloric acid in ethanol results in required trans-dorzolamide hydrochloride.

PCT patent publication WO2007122130 discloses the process for preparation of (4S,6S)-4-(ethylamino)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide, wherein racemic 4-(ethylamino)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide having trans:cis diastereomeric mixture of 80:20 is treated with maleic acid in acetone to isolate racemic trans-4-(ethylamino)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide maleate salt having trans:cis diastereomeric mixture of 95:5. The isolated maleate salt is then treated with base and reacted with (1 S)-(+)-10-camphorsulfonic acid to get corresponding (4S,6S)-4-(ethylamino)-6-methyl-5, 6-di hydro-4H -thi eno[2, 3- b] thi opy ran-2-sul f onami de 7, 7-di ox i de ( 1 S ) -( + )- 10-camphorsulfonate salt, which is neutralized to give pure (4S,6S)-4-(ethylamino)-6- methyl -5, 6-di hydro-4H -thi eno[2,3- b] thi opyran-2-sulf onami de 7, 7-di oxi de.

PCT patent publication W 02008135770 discloses the process for the preparation of dorzolamide hydrochloride, wherein the racemic 4-(ethylamino)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide is treated with

carboxylic acid selected from the group consisting of fumaric acid, benzoic acid, acetic acid, salicylic acid and p-hydroxybenzoic acid, which selectively forms an acid addition salt with the trans- isomer and removes the undesirable c is- isomer from the mixture of cis and trans- isomers. The trans-4-(ethylamino)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide acid addition salt is converted to trans-(e)-4-(ethylamino)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide by conventional methods. The compound trans-(e)-4-(ethylamino)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide is resolved with di-p-toluoyl-L -tartaric acid followed by neutralization of the chiral salt yields the compound (4S,6S)4-(ethylamino)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide, which on reaction with hydrochloric acid in isopropanol results in the required (4S,6S)4-( ethyl ami no) – 6- methyl -5, 6- di hydro-4H -thi eno[2, 3- b] thi opy ran-2-sul f onami de 7, 7-di oxide hydrochloride.

PCT patent publication WO2010061398 discloses the process for the preparation of dorzolamide hydrochloride, wherein the racemic 4-(ethylamino)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide is treated with maleic acid in water to get trans-dorzolamide maleate salt. The maleate salt is further neutralized and then resolution with di-p-toluoyl-L -tartaric acid followed by neutralization of the chiral salt yields (4S,6S)-4-(ethylamino)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide. The compound (4S,6S)-4-(ethylamino)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide on reaction with hydrochloric acid in isopropanol results in the required pure trans-dorzolamide hydrochloride.

PCT patent publication WO2011101704 and corresponding Indian Patent application 426/C H E/2010 describes the process for the preparation of trans-dorzolamide hydrochloride by forming the maleate salt of racemic 4-( ethyl ami no) – 6- methyl -5, 6- di hydro-4H -thi eno[2, 3- b] thi opy ran-2-sul f onami de 7, 7-di oxide. The maleate salt is further neutralized and then resolution with di-p-

toluoyl-L -tartaric acid followed by neutralization of the chiral salt yields trans-(4S,6S)-4-(ethylamino)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide. The compound trans-(4S,6S)-4-(ethylamino)-6-methyl- 5.6- dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide on reaction with hydrochloric acid in isopropanol results in the required trans-(S,S)-dorzol amide hydrochloride.

Indian Patent application 3431 /M U M/2012 discloses the process wherein racemic 4-( ethyl ami no) -6- methyl – 5, 6- di hydro-4H -thi eno[2, 3- b] thi opy ran-2-sul f onami de

7.7- dioxide is resolved using di benzoyl- L -tartaric acid monohydrate or di-p-toluoyl-L -tartaric acid monohydrate in methanol followed by neutralization of the chiral salt and then the (4S,6S)-4-(ethylamino)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide thus obtained is treated with hydrochloric acid in isopropanol to result in the required trans-(S,S)-dorzolamide hydrochloride. The compound is further recrystallised in isopropanol to isolate pure dorzol amide hydrochloride.

The prior art processes disclosed as above have several drawbacks in the preparation of pure trans-dorzolamide hydrochloride viz.,

1. involves column chromatography for separation of the desired diastereomer;

2. involves preparation of corresponding diastereomeric salts and converting again to base before preparation and isolation of pure trans-dorzolamide hydrochloride;

3. involves additional step of reacting the racemic dorzolamide base with mineral acid to isolate corresponding dorzolamide salt which is again converted to dorzolamide base and further resolved using resolving agent to form the corresponding salt, neutralization and isolation of the chiral dorzolamide base before reacting with hydrochloric acid to obtain dorzolamide hydrochloride; and

4. involves an additional step of reacting the racemic dorzolamide base with carboxylic acid to isolate corresponding dorzolamide salt which is again converted to dorzolamide base and resolved using resolving agent to form the corresponding salt, neutralization and isolation of the chiral dorzolamide base before reacting with hydrochloric acid to obtain dorzolamide hydrochloride.

As is evident from the cursory review of the prior arts that the preparation of pure dorzolamide hydrochloride involves either column chromatography for isolation of trans- isomer followed by use of resolving agent or involves repeated preparations of chiral or diastereomeric salts, use of resolving agent followed by converting into dorzolamide base and then isolating pure dorzolamide hydrochloride devoid of the diastereomeric impurity of cis-isomer.

Therefore, there remains a need in the art to develop a simple and cost effective process for the preparation of dorzolamide hydrochloride which ameliorates the above drawbacks of the prior arts and makes the process industrially viable and economically advantageous. The present invention therefore seeks to address these issues by providing an improved and cost-effective process that can easily be scaled for industrial production of dorzolamide hydrochloride.

The present inventors have developed an alternative process for isolating pure dorzolamide hydrochloride substantially free from the cis-isomer without using the time consuming column chromatography technique, repeated preparation of chiral salts, diastereomeric salts and converting into base before hydrochloride salt formation to isolate pure trans-(S,S)-dorzolamide hydrochloride.

E xamples:

E xample 1 : Preparation of (6S)-4-(ethylamino)-6-methyl-5,6-dihydro-4H -thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide hydrochloride:

In a dry flask charged (6S)-4-(ethylamino)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide (50.0 gm) in acetone (700 ml) under stirring and cooled to OeC. Maintaining the temperature at OeC to 5eC purged hydrochloric acid gas to adjust the pH to acidic between the range of 1-2. After attaining desired pH, maintained the reaction mass for two hours at OeC to 5eC under stirring. Filtered the precipitated compound (6S)-4-(ethylamino)-6-methyl-5, 6-di hydro-4H -thi eno[2,3- b] thi opyran-2-sulf onami de 7,7-di oxi de hydrochl ori de and washed the solid mass with chilled acetone (50 ml). Dried the compound at 60-65eC till constant weight.

Dry weight: 50 g

H PL C purity: 77.62% [cis-isomer: 22.11 % ]

E xample 2: Preparation of trans-(4S,6S)-4-(ethylamino)-6-methyl-5,6-dihydro-4H -thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide hydrochloride [C rude dorzolamide hydrochloride]:

In a dry flask charged (6S)-4-(ethylamino)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide hydrochloride (19.0 g) and methanol (190 ml) at temperature of 25eC to 30eC. Under stirring raised the temperature of the reaction mass to reflux and maintained at reflux temperature for a period of two hours. After maintaining cooled the reaction mass gradually to 10eC to 15eC. Filtered the compound trans-(4S,6S)-4-(ethylamino)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide hydrochloride and washed the solid mass with chilled methanol. Dried the compound at 60-65eC till constant weight.

Dry weight: 12.8 g

H PL C purity: 99.33% [cis-isomer: 0.5% ]

E xample 3: Purification of trans-(4S,6S)-4-(ethylamino)-6-methyl-5,6-dihydro-4H -thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide hydrochloride: In a dry flask charged trans-(4S,6S)-4-(ethylamino)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide hydrochloride (11.0 g), acetone (11 ml) and purified water (5.5 ml) at the temperature of 25eC to 30eC. Raised the temperature of the reaction slurry to reflux and maintained at reflux for one hour. Diluted the reaction mass with fresh acetone (44 ml) maintaining the temperature at reflux and continued maintaining at reflux temperature further for one hour. Cooled the reaction mass gradually to 10eC to 15eC and maintained. Filtered the compound pure (4S,6S)-4-(ethylamino)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide hydrochloride solid mass and washed the pure compound with chilled acetone (11 ml). Dried at 55eC to 60eC till constant weight.

Dry weight: 8.8 g

H PL C purity: 99.89% [cis-isomer: not detected]

[T otal impurities: 0.11 % ]

E xample 4: Preparation of trans-(4S,6S)-4-(ethylamino)-6-methyl-5,6-dihydro-4H -thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide hydrochloride [C rude dorzolamide hydrochloride]:

Charged (6S)-4-(ethylamino)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide hydrochloride (5.0 g), methanol (22.5 ml) and 2.5 ml purified water at temperature of 25eC to 30eC. Under stirring raised the temperature of the reaction mass to reflux and maintained at reflux temperature for a period of two hours. After maintaining cooled the reaction mass gradually to 30eC to 35eC. Filtered the solid compound trans-(4S,6S)-4-(ethylamino)-6-methyl-5,6-dihydro-4H-thieno[2,3-b]thiopyran-2-sulfonamide 7,7-dioxide hydrochloride and washed with methanol (10 ml). Dried the compound at 60eC to 65eC till constant weight.

Dry weight: 3.2 g

H PL C purity: 99.47% [cis-isomer: 0.43% ]

////////WO 2018066004, NEW PATENT, INDOCO REMEDIES LIMITED, DORZOLAMIDE

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WO 2018067805, NEW PATENT, SOTAGLIFLOZIN, TEVA


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WO-2018067805

(WO2018067805) SOLID STATE FORMS OF SOTAGLIFLOZIN

TEVA PHARMACEUTICAL INDUSTRIES LTD.

GIAFFREDA, Stefano Luca; (IT).
MODENA, Enrico; (IT).
IANNI, Cristina; (IT).
MUTHUSAMY, Anantha Rajmohan; (IN).
KANNIAH, Sundara Lakshmi; (IN)

Stefano Luca Giaffreda at PolyCrystallineStefano Luca Giaffreda

Enrico Modena at PolyCrystallineEnrico Modena

Sundara Lakshmi KanniahSundara Lakshmi Kanniah
Novel crystalline forms of sotagliflozin (designated as Forms A and E) and their hydrate and monohydrate, processes for their preparation and compositions comprising them are claimed. Also claims are their use for treating diabetes. Sotagliflozin is known to be an inhibitor of sodium glucose transporter-1 and -2, useful for treating insulin dependent diabetes and non-insulin dependent diabetes

Sotagliflozin has the chemical name (2S,3R,4R,5S,6R)-2-(4-chloro-3-(4-ethoxybenzyl)phenyl)-6-(methylthio)tetrahydro-2H- pyran-3,4,5-triol. Sotagliflozin has the following chemical structure:

[0003] Sotagliflozin is an orally available L-xyloside based molecule that apparently inhibits both sodium-glucose transporter type 1 (SGLT1) and type 2 (SGLT2). SGLT1 is primarily responsible for glucose and galactose absorption in the gastrointestinal tract, and SGLT2 is responsible for most of the glucose reabsorption performed by the kidney.

[0004] Sotagliflozin is known from WO 2008/109591. Amorphous forms and crystalline forms (i.e. Form 1 and Form 2) of Sotagliflozin are disclosed in WO2010/009197.

[0005] Polymorphism, the occurrence of different crystal forms, is a property of some molecules and molecular complexes. A single compound, like Sotagliflozin, may give rise to a variety of polymorphs having distinct crystal structures and physical properties like melting point, thermal behaviors (e.g. measured by thermogravimetric analysis – “TGA”, or differential scanning calorimetry – “DSC”), powder X-ray diffraction (PXRD) pattern, infrared absorption fingerprint, Raman absorption fingerprint, and solid state (13C-) NMR spectrum. One or more of these techniques may be used to distinguish different polymorphic forms of a compound.

[0006] Different salts and solid state forms (including solvated forms) of an active pharmaceutical ingredient may possess different properties. Such variations in the properties of different salts and solid state forms and solvates may provide a basis for improving

formulation, for example, by facilitating better processing or handling characteristics, improving the dissolution profile, or improving stability (polymorph as well as chemical stability) and shelf-life. These variations in the properties of different salts and solid state forms may also provide improvements to the final dosage form, for instance, if they serve to improve bioavailability. Different salts and solid state forms and solvates of an active pharmaceutical ingredient may also give rise to a variety of polymorphs or crystalline forms, which may in turn provide additional opportunities to use variations in the properties and characteristics of a solid active pharmaceutical ingredient for providing an improved product.

[0007] Discovering new salts, solid state forms and solvates of a pharmaceutical product can provide materials having desirable processing properties, such as ease of handling, ease of processing, storage stability, and ease of purification or as desirable intermediate crystal forms that facilitate conversion to other salts or polymorphic forms. New salts, polymorphic forms and solvates of a pharmaceutically useful compound can also provide an opportunity to improve the performance characteristics of a pharmaceutical product (dissolution profile, bioavailability, etc.). It enlarges the repertoire of materials that a formulation scientist has available for formulation optimization, for example by providing a product with different properties, e.g., a different crystal habit, higher crystallinity or polymorphic stability which may offer better processing or handling characteristics, improved dissolution profile, or improved shelf-life. For at least these reasons, there is a need for additional salts and solid state forms (including solvated forms) of Sotagliflozin.

EXAMPLES

Sotagliflozin Form-2 may be prepared according to WO2010/009197. Sotaglifiozin Form-2 may also be prepared according to Example 16 below.

Working examples:

Example- 1 : Preparation of Sotagliflozin (Amorphous Form)

[0080] 2 g of Sotagliflozin (Form-2) was taken in 250ml round bottom flask and applied vacuum (approx. 50 mbar) with continuous rotation of the flask. The flask was externally heated by hot air flow maintained at few centimetres from the rotating flask wall for few minutes until the compound melts at around 130°C and the melt was quenched to room temperature (25°C) with water bath. The amorphous solid (1.8 g) was scratched from the walls of the flask.

Example-2: Preparation of Sotagliflozin Form A

[0081] 100 mg of Sotagliflozin (Amorphous form, prepared according to example 1) was suspended in 2 ml of water, was left at variable temperature as follows: heating from 10°C to 50°C at the rate of 20°C/hr, held at 50°C for 3 hrs; cooling from 50°C to 10°C at the rate of 20°C/hr, held at 10°C for 3hrs; again heating from 10°C to 50°C at the rate of 10°C/hr, held at 50°C for 3hrs; again cooling from 50°C to 10°C at the rate of 10°C/hr, held at 10°Cfor 3hrs; further heating from 10°C to 50°C at the rate of 5°C/hr, held at 50°C for 3hrs; further cooling from 50°C to 10°C at the rate of 5°C/hr, held at 10°C for 3hrs; followed by raising the temperature from 10°C to 25°C at the rate of 10°C/hr, held at 25°C for 24hrs. The suspension was filtered under vacuum and was dried at room temperature by vacuum suction. Sotagliflozin Form A has been confirmed by PXRD as presented in figure 1.

Example-3 : Preparation of Sotagliflozin Form B

[0082] 100 mg of Sotagliflozin (Amorphous form, prepared according to example 1) was suspended in 2 ml of Toluene at room temperature (20-25 °C). The suspension was stirred for 15days which was filtered under vacuum and was dried at room temperature by vacuum suction. Sotagliflozin Form B has been confirmed by PXRD as presented in figure 2.

Example-4: Preparation of Sotagliflozin Form B

[0083] 100 mg of Sotagliflozin (Amorphous form, prepared according to example 1) was suspended in 2 ml of Heptane at room temperature (20-25 °C). The suspension was stirred for 15days which was filtered under vacuum and was dried at room temperature by vacuum suction. Sotagliflozin Form B has been confirmed by PXRD.

Example-5 : Preparation of Sotagliflozin Form B

[0084] 100 mg of Sotagliflozin (Amorphous form, prepared according to example 1) was suspended in 2 ml of Mesitylene at room temperature (20-25°C). The suspension was stirred for 15days which was filtered under vacuum and was dried at room temperature by vacuum suction. Sotagliflozin Form B has been confirmed by PXRD.

Example-6: Preparation of Sotagliflozin Form B

[0085] 100 mg of Sotagliflozin (Amorphous form, prepared according to example 1) was suspended in 2 ml of p-Xylene at room temperature (20-25 °C). The suspension was stirred for 15days which was filtered under vacuum and was dried at room temperature by vacuum suction. Sotagliflozin Form B has been confirmed by PXRD.

Example-7: Preparation of Sotagliflozin Form C

[0086] 100 mg of Sotagliflozin (Amorphous form, prepared according to example 1) was suspended in 2 ml of Water at 50°C. The suspension was stirred for 72hrs which was filtered under vacuum and was dried at room temperature by vacuum suction. Sotagliflozin Form C has been confirmed by PXRD as presented in figure 3.

Example-8: Preparation of Sotagliflozin Form D

[0087] 30 mg of Sotagliflozin (Form-2) was dissolved in 3ml of ethanol. The solution was stirred at 25°C for lhr (for dissolution) and then filtered. The solution was kept in a 20 ml vial and left open to allow evaporation of the solvent (25°C/1 atm). Solid was observed after 3 days; it was collected and analyzed by PXRD. Sotagliflozin Form D has been confirmed by PXRD as presented in figure 4.

Example-9: Preparation of Sotagliflozin Form E

[0088] 30 mg of Sotagliflozin (Form-2) was dissolved in 3ml of isopropyl acetate. The solution was stirred at 25°C for lhr (for dissolution) and then filtered. The solution was kept in a 20ml vial and left opened in the refrigerator (4-7°C/l atm) to allow evaporation of the solvent. The crystals were observed after 9 days; it was collected and analyzed by PXRD. Sotagliflozin Form E has been confirmed by PXRD as presented in figure 5.

Example-9: Preparation of Sotagliflozin Form F

[0089] 30 mg of Sotagliflozin (Form-2) was dissolved in 3ml of 2-propanol. The solution was stirred at 25°C for lhr (for dissolution) and then filtered. The solution was kept in a 20ml vial and left opened to allow evaporation of the solvent (4-7°C/l atm). The crystals were observed after 13 days; it was collected and analyzed by PXRD. Sotagliflozin Form F has been confirmed by PXRD as presented in figure 6.

Example- 10: Preparation of Sotagliflozin Form G

[0090] 30 mg of Sotagliflozin (Form-2) was dissolved in 3ml of 1 -propanol. The solution was stirred at 25°C for lhr (for dissolution) and then filtered. The solution was kept in a 20ml vial and left opened in the refrigerator (4-7°C/l atm) to allow evaporation of the solvent. Solid was observed after 24 days; it was collected and analyzed by PXRD.

Sotagliflozin Form G has been confirmed by PXRD as presented in figure 7.

Example- 11 : Preparation of Sotagliflozin Form H

[0091] 15 mg of Sotagliflozin (Form- A) was kept in DVS (dynamic vapor sorption) instrument. The kinetic sorption measurement was performed at 25 °C in two full cycle of sorption and desorption as follows, from 40%RH to 90%RH, 90%RH to 0%RH then again from 0% to 90%RH, 90%RH to 0%RH. After completion of experiment, the powder was collected and analyzed by PXRD. Sotagliflozin Form H has been confirmed by PXRD as presented in figure 8.

Example- 12: Preparation of Sotagliflozin Form I

[0092] Procedure to prepare saturated solution: 1500 mg of Sotagliflozin were dissolved in 1ml of 2-Methoxyethanol and the solution was stirred overnight at 25°C; the solution was then filtered. Taken ΙΟΟμί from above saturated stock solution, 500μί of Diisopropylether was added drop by drop, no solid was observed left the solution overnight under stirring, added again 500μί of Diisopropylether into the entire solution. The solid was precipitated, stirred for 30min and filtered under vacuum. Sotagliflozin Form I has been confirmed by PXRD as presented in figure 9.

Example-13: Preparation of Sotagliflozin Form K

[0093] 10-20mg of Sotagliflozin (Form D) was kept for drying in a natural air convection oven (MPM instruments modelM40-VN) at 60°C for lh. Sotagliflozin Form K has been confirmed by PXRD as presented in figure 10.

Example-14: Preparation of Sotagliflozin Form E:

[0094] Sotagliflozin (2g) and ethyl acetate (6ml) were heated to reflux temperature (71-74°C). Heptane (6ml) was added at reflux, reaction mass was stirred for additional 15 minutes and then cooled to room temperature. Solid was precipitated out during cooling at about 57°C. A mixture of ethyl acetate and heptane (1 : 1 v/v, 24 ml) was added and the reaction mixture was heated to reflux temperature (71-74°C) to obtain a clear solution which was maintained for 15 minutes. Reaction mass was cooled to room temperature (25-30°C) and stirred for 3 hours. The slurry was filtered, washed with a mixture of ethyl acetate and heptane (l : lv/v, 8ml) and dried under vacuum at 50°C for 2Hrs. The obtained solid (1.8g) was analyzed by PXRD-Form E.

Example-15: Preparation of Sotagliflozin Form D:

[0095] 2g of sotagliflozin Form F was kept in glass petri-dish and exposed to 80%RH for 60hrs at room temperature. Solid was collected (2g) and analyzed for PXRD-Form D.

Example-16: Preparation of Sotagliflozin Form 2:

[0096] 50 gm of (2S,3S,4R,5S,6R)-2-(4-chloro-3-(4-ethoxybenzyl)phenyl)-6-(Methylthio) tetrahydro-2H-pyran-3,4,5-triyl triacetate (SOT-1) and 500ml of methanol were charged in round bottom flask, the slurry was cooled to 20°C then added sodium methoxide solution prepared in methanol (2.45gm of sodium methoxide in 50ml of methanol) at 20°C

over the period of 10 min and stirred the mass for 2hr at 20°C.The reaction completion was ensured by HPLC. Once the reaction is completed added 2.5gm Norit carbon to the reaction mass at 23°C and stirred for 30min. Filtered the reaction mass through Hyflo bed and washed with 20ml of methanol. Taken the filtrate into the flask and concentrated under vacuum at 45°C up to 3 volumes with respect to SOT-1 then cooled to 21°C over the period of 60 min, added 560ml of Water at 21°C over the period of 30min and stirred for 30min at 21 °C, the reaction mass left overnight (without stirring) and stirred for lhr. The obtained slurry was filtered under vacuum and washed with 55ml*3times of water then kept for suction at 20-30°C for 30min. The material was dried at 50-60°C for 9hrs under vacuum to obtain 35gm of Sotagliflozin. 5.7gm of Sotagliflozin (5.7gr, Sotagliflozin) and 28.5ml of Methyl ethyl ketone (28.5ml) were charged in round bottom flask, the slurry was stirred at 22-25°C for 5-10min gradually raised the temperature to 78°C then added 114 ml of n-Heptane (114ml) at 78°C over the period of 55min. Once the addition of n-heptane was completed, seeds of Form-2 (20 mg) were added, the slurry was gradually cooled down to 25-27°C over the period of 60 min. The obtained slurry was stirred for 2-3hrs at 25-27°C and the mass was kept overnight (without stirring) at 25-27°C then stirred for 3hr at 23 °C. The mass was filtered under vacuum and washed with 10ml of n-Heptane then kept for suction for 30min at 25-30°C. The material was dried at 50°C for 2hrs under vacuum to obtain Form-2 of Sotagliflozin.

Preparation of Form 2- Seeds

[0097] Sotagliflozin (2gr, amorphous) was dissolved in methyl ethyl ketone (10ml) The slurry was heated to 80°C, then n-Heptane (40ml) was added over 60mins. The hazy solution was cooled to 20-30° over 60mins and stirred for 3hr. The slurry was kept overnight at 20-30°C (without stirring). The obtained slurry was filtered under vacuum and washed with n-Heptane (10ml) . The material was dried at 50 °C for 4hrs under vacuum to obtain the 1.9gm of Sotagliflozin Form -2 as confirmed by PXRD.

///////////WO 2018067805, NEW PATENT,  SOTAGLIFLOZIN, TEVA

DAROLUTAMIDE, WO 2018036558, 苏州科睿思制药有限公司 , New patent


DAROLUTAMIDE, WO 2018036558, 苏州科睿思制药有限公司 , New patent

CRYSTAL FORM OF ANDROGEN RECEPTOR ANTAGONIST MEDICATION, PREPARATION METHOD THEREFOR, AND USE

张晓宇 [CN]

一种式(I)所示ODM-201的晶型B,其特征在于,其X射线粉末衍射在衍射角2θ为16.2°±0.2°、9.0°±0.2°、22.5°±0.2°处有特征峰。

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Novel crystalline forms of an androgen receptor antagonist medication, particularly ODM-201 (also known as darolutamide; designated as Forms B and C), processes for their preparation and compositions comprising them are claimed. Represents a first filing from Crystal Pharmaceutical Co Ltd and the inventors on this API.

Orion and licensee Bayer are codeveloping darolutamide, an androgen receptor antagonist, for treating castration-resistant prostate cancer and metastatic hormone-sensitive prostate cancer.

专利CN102596910B公开了ODM-201的制备方法,但并未公开任何的晶型信息。专利WO2016120530A1公开了式(I)(CAS号:1297538-32-9)所示的晶型I,式(Ia)(CAS号:1976022-48-6)所示的晶型I’和式(Ib)(CAS号:1976022-49-7)所示的晶型I”。文献Expert Rev.Anticancer Ther.15(9),(2015)已报道:ODM-201是由1:1比例的(Ia)和(Ib)两种非对应异构体组成,即为式(I)所示结构。因此,现有关于ODM-201的晶型只有晶型I报道。

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Prostate cancer has become an important disease threatening the health of men. Its incidence is higher in western countries and shows a year-by-year upward trend. In the past, Asian countries with a lower incidence of the disease have also seen an increase in the number of patients in recent years. Clinical treatment of prostate cancer commonly used methods are surgical resection, radiation therapy and blocking androgen endocrine therapy. Androgen is closely related to the growth of prostate and the occurrence of prostate cancer. Therefore, endocrine therapy has become an effective way to treat prostate cancer. The method includes orchidectomy, estrogen therapy, gonadotropin-releasing hormone analog therapy, gonadotropin-releasing hormone antagonist therapy, androgen antagonistic therapy, etc., wherein androgen antagonist therapy can be both early treatment of prostate cancer can also be combined Surgery for adjuvant therapy is currently one of the main clinical treatment of prostate cancer. Androgen receptor as a biological target of androgen play an important role in the field of biomedical research.

Clinical trials have shown that exogenous androgen administration to patients with prostate cancer can lead to an exacerbation of the patient’s condition; conversely, if the testicles are removed and the level of androgens in the patient is reduced, the condition is relieved, indicating that androgens contribute to the development of prostate cancer Significant influence. According to receptor theory, androgen must bind with androgen receptor (AR) to cause subsequent physiological and pathological effects, which is the basis for the application of androgen receptor (AR) antagonist in the treatment of prostate cancer. In vitro experiments have shown that AR antagonists can inhibit prostate cell proliferation and promote apoptosis. Depending on the chemical structure of AR antagonists, they can be divided into steroidal AR antagonists and non-steroidal AR antagonists. Non-steroidal anti-androgen activity is better, there is no steroid-like hormone-like side effects, it is more suitable for the treatment of prostate cancer.

ODM-201 (BAY-1841788) is a non-steroidal oral androgen receptor (AR) antagonist used clinically to treat prostate cancer. The binding affinity of ODM-201 to AR was high, with Ki = 11nM and IC50 = 26nM. Ki was the dissociation constant between ODM-201 and AR complex. The smaller the value, the stronger the affinity. half maximal inhibitory concentration “refers to the half-inhibitory concentration measured, indicating that a certain drug or substance (inhibitor) inhibits half the amount of certain biological processes. The lower the value, the stronger the drug’s inhibitory ability. In addition, ODM-201 does not cross the blood-brain barrier and can reduce neurological related side effects such as epilepsy. Bayer Corporation has demonstrated in clinical trials the effectiveness and safety of ODM-201, demonstrating its potential for treating prostate cancer.

The chemical name of ODM-201 is: N – ((S) -l- (3- (3- chloro-4-cyanophenyl) -lH-pyrazol-l-yl) -propan- The chemical name contains the tautomer N – ((S) -1- (3- (3- 4-cyanophenyl) -1H-pyrazol- 1 -yl) -propan-2-yl) -5- (1 -hydroxyethyl) 1297538-32-9, the structural formula is shown in formula (I) :

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The different crystalline forms of solid chemical drugs can lead to differences in their solubility, stability, fluidity and compressibility, thereby affecting the safety and efficacy of pharmaceutical products containing the compounds (see K. Knapman, Modern Drug Discovery, 3, 53 -54,57,2000.), Resulting in differences in clinical efficacy. It has been found that new crystalline forms (including anhydrates, hydrates, solvates, etc.) of the active ingredients of the medicinal product may give rise to more processing advantages or provide substances with better physical and chemical properties such as better bioavailability, storage stability, ease Processed, purified or used as an intermediate to promote conversion to other crystalline forms. The new crystalline form of the pharmaceutical compound can help improve the performance of the drug and broaden the choice of starting material for the formulation.

Patent CN102596910B discloses the preparation of ODM-201, but does not disclose any crystal form information. Patent WO2016120530A1 discloses a crystalline form I represented by the formula (I) (CAS number: 1297538-32-9), a crystalline form I ‘represented by the formula (Ia) (CAS number: 1976022-48-6) and a compound represented by the formula (CAS No. 1976022-49-7). Document Expert Rev. Anticancer Ther. 15 (9), (2015) It has been reported that ODM-201 is composed of a 1: 1 ratio of (Ia) And (Ib), which is the structure shown in Formula (I), so the only existing crystal form I for ODM-201 is reported.

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However, the lower solubility of Form I and the high hygroscopicity, and the preparation of Form I requires the use of highly toxic acetonitrile solvents, which are carcinogenic in animals and are the second class of solvents that should be controlled during the process development stage. Form I preparation method is more complex, long preparation cycle, the process needs heating, increasing the cost of industrial preparation, is not conducive to industrial production. In order to overcome the above drawbacks, there is still a need in the art for a systematic and comprehensive development of other polymorphs of ODM-201 of formula (I), simplifying the preparation thereof, enabling its pharmacological development and releasing its potential, Preparation of a better formulation of the drug ingredients.

The inventors found through experiments that Form B and Form C of the present invention, and found that Form B and Form C of the present invention have more excellent properties than the prior art. Dissolution is a prerequisite for drug absorption, and increased solubility will help to increase the bioavailability of the drug and thereby improve the drug’s druggability. Compared with the prior art, the crystalline forms B and C of the invention have higher solubility and provide favorable conditions for drug development. Compared with the prior art, the crystalline forms B and C of the invention also have lower hygroscopicity. Hydroscopic drug crystal form due to adsorption of more water lead to weight changes, so that the raw material crystal component content is not easy to determine. In addition, the crystalline form of the drug substance absorbs water and lumps due to high hygroscopicity, which affects the particle size distribution of the sample in the formulation process and the homogeneity of the drug substance in the preparation, thereby affecting the dissolution and bioavailability of the sample. The crystal form B and the crystal form C have the same moisture content under different humidity conditions, and overcome the disadvantages caused by high hygroscopicity, which is more conducive to the long-term storage of the medicine, reduces the material storage and the quality control cost.

In addition, the present invention provides Form B and Form C of ODM-201 represented by formula (I), which have good stability, excellent flowability, suitable particle size and uniform distribution. The solvent used in the preparation method of crystal form B and crystal form C of the invention has lower toxicity, is conducive to the green industrial production, avoids the pharmaceutical risk brought by the residue of the toxic solvent, and is more conducive to the preparation of the pharmaceutical preparation. The novel crystal type provided by the invention has the advantages of simple operation, no need of heating, short preparation period and cost control in industrialized production. Form B and Form C of the present invention provide new and better choices for the preparation of pharmaceutical formulations containing ODM-201, which are of great significance for drug development.

The problem to be solved by the invention

The main object of the present invention is to provide a crystal form of ODM-201 and a preparation method and use thereof.

//////////DAROLUTAMIDE, WO 2018036558, 苏州科睿思制药有限公司 , New patent, CRYSTAL

Drug Patents International


All about Patents and Intellectual property by DR ANTHONY MELVIN CRASTO, worlddrugtracker, Ph.D ( ICT, Mumbai) , INDIA 29Yrs Exp. in the feld of Organic Chemistry, Serving chemists around the world. THE VIEWS EXPRESSED ARE MY PERSONAL AND IN NO-WAY SUGGEST THE VIEWS OF THE PROFESSIONAL BODY OR THE COMPANY THAT I REPRESENT, amcrasto@gmail.com, +91 9323115463 India

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SOFOSBUVIR, NEW PATENT, WO 2018032356, Pharmaresources (Shanghai) Co Ltd


Image result for PHARMARESOURCES (SHANGHAI) CO., LTD

SOFOSBUVIR, NEW PATENT, WO 2018032356, Pharmaresources (Shanghai) Co Ltd

WO-2018032356, Pharmaresources (Shanghai) Co Ltd

CHEN, Ping; (CN).
PENG, Shaoping; (CN).
LI, Yinqiang; (CN).
LI, Dafeng; (CN).
DONG, Xuejun; (CN)

Process for the preparation of lactone derivatives and their intermediates are important precursors for the synthesis of anti-hepatitis C virus agents, including sofosbuvir . Represents a first filing from Pharmaresources (Shanghai) Co Ltd and the inventors on this API. Gilead Sciences , following its acquisition of Pharmasset , has developed and launched sofosbuvir, a pure chiral isomer of PSI-7851, a next-generation HCV uracil nucleotide analog polymerase inhibitor prodrug for once-daily oral use.

Hepatitis C virus (HCV) infection represents a global health thereat in need of more effective treatment options. The World Health Organization (WHO) estimates that 130-170 million of individuals worldwide have detectable antibodies to HCV and approximately 60-85%of this population develops into chronic disease, leading to liver cirrhosis (5-25%) and hepatocellular carcinoma (1-3%) and liver failure. While there were existing therapeutics including pegylated interferon- (Peg-IFN) and ribavirin (RBV) , they are suboptimal due to various adverse effects, intolerability, low efficacy and slow response in reducing the viral loads across the multiple genotypes (1-6) of HCV. Therefore, there is an urgent and enormous need to develop more effective and efficacious novel anti-HCV therapies.
During the past decade, there have been a variety of small molecule agents as direct-acting antivirals (DAAs) targeting HCV viral replication via action on both structural and nonstructural proteins (NS3-5) have been launched inmarket or in late-stage clinical development. Among the DAAs reported, Soforsbuvir (brand name Sovaldi) targeting NS5B protein from Gilead was approved by FDA in 2003 for HCV genotypes 2 and 3 (in combination with Ribavin) . In 2014, a combination of Sofosbuvir with viral NS5A inhibitor Ledipasvir (brand name Harvoni) was approved. This combination provides high cure rates in people infected with HCV genotype 1, the most common subtype in the US, Japan, and much of the Europe, without the use of interferon, and irrespective of prior treatment failure or the presence of cirrhosis. Compared to previous treatment, Sofosbuvir-based regimens provide a higher cure rate, fewer side effects, and a 2-4 fold reduced duration of therapy.
Sofosbuvir is a prodrug using the ProTide biotechnology strategy. It is metabolized to the active antiviral agent 2′-deoxy-2′-α-fluoro-β-C-methyluridine-5′-triphosphate. The triphosphate serves as a defective substrate for the NS5B protein, which is the viral RNA polymerase, thus acts as an inhibitor of viral RNA synthesis.
Due to the tremendous success in Sorosbuvir-based oral therapy, there remains a need for a more efficient method for making sofosbuvir-like anti-hepatitis C virus agents, including sofosbuvir and intermediates thereof. A variety of methods describing different synthetic approaches for substituted lactone (VI) shown below, a key intermediate for Sofosbuvir and its like anti-viral drugs have been published.
WO2008045419 reported a seven-step synthesis (Scheme 1) for the γ-lactone intermediate. When chiral glyceraldehyde used as the starting material, two new chiral centers were generated following Witting reaction and dihydoxylation. After cyclic sulfonate formed, the fluoro subsititution was introduced stereospecifically by a SN2 reaction with HF-Et3N. Lactonization was achieved under the acid conditions followed by hydroxy protecting step to give the desired intermediate. The main disadvantage of this approach is that considerable quantities of both solid and acidic liquid wastes were produced during the process which is very difficult to handle with (e.x. filtration) and/or contributes to the enviroment pollution upon disposal.
Scheme 1
In a similar process reported in CN105418547A (Scheme 2) , the Witting product was epoxidized followed by ring-opening fluorolation by HF-Et3N or other fluoro-containing reagents, significant amount of regioisomer was observed which was difficult to remove from the oily mixture.
Scheme 2
US20080145901 reported an enzymetic approach to the γ-lactone intermediate (scheme 3) . Treatment of ethyl 2-fluoro-propinate with chiral glyceraldehyde to form the aldol adducts consisting the mixture of four disteroisomers. The disteroisomers were selectively hydrolyzed by enzyme and the major isomer was obtained. After lactonization and hydroxyl protecting, other two isomers were removed by recrystallization.
WO2008090046 reported a similar synthesis as described in Scheme 3.2-fluoro-propionic acid was converted to diffirent bulky ester or amide and reacted with chiral glyceraldehydes. The mixture of the disteroisomers were purified by recrystallization to obtain the pure isomer. By using the method described in Scheme 3, the γ-lactone can be scale up to kilogram quantities but the de value of the final product can not achieve desired level.
Scheme 3
In WO2014108525, WO2014056442 and CN105111169, diffirent auxiliaries were used in the Aldol Reaction to improve the disteroisomeric selectivity (Scheme 4) . The process was shortened to 3~4 steps and the de value was increase significantly.
Scheme 4
Examples
Example 1: preparation of 2-fluoropropanoyl chloride (3)
Chlorosulfonic acid (660 mL, 10 mol, 20 eq) was added to a solution of phthaloyl dichloride (1.4 L, 10 mol, 20 eq) and ethyl-2-fluoropropanoate (600 g, 5 mol) at room temperature. The solution was heated at 120 ℃ for 4 hs. 2- (R) -fluoropropanoyl chloride was distilled from the reaction mixture under reduced pressure and recovered as a colourless oil (320 g, 58.2%) . 1H-NMR (CDCl3, 400 MHz) : δ 5.08 (dq, J = 48.8, 6.8 Hz, 1 H) , 1.63 (dd, J =22.8, 6.8 Hz, 3 H) .
Example 2: preparation of (4R) -3- (2-fluoropropanoyl) -4-isopropyloxazolidin-2-one (4)
n-Butyl lithium (2.5 M in hexane, 30 mL, 75 mmol, 1.1 eq) was added to a solution of 4-(R) -4-isopropyl-2-oxazolidinone (8.8 g, 68.2 mmol, 1 eq) in dry THF (80 mL) at -50 ℃ under N2 atomosphere. After 30 min, 2-fuoropropanoyl chloride (6.8 mL, 0.9 eq) was added, and the solution was stirred for 4 hs at -50 ℃. The reaction was then quenched with a saturated solution of NH4Cl (50 mL) , extracted with MTBE (80 mL *2) , washed with brine and dried over MgSO4. Solvents were removed under reduced pressure. The product was purified over silica (Hexane/EtOAc= 10/1) and recovered as a brown oil (9 g, 74.8%) . 1H-NMR (CDCl3, 400 MHz) : δ 6.00 (dm, J = 49.2Hz, 1 H) , 4.27 -4.53 (m, 3 H) , 2.43 (dm, J = 52.6 Hz, 1 H) , 1.63 (td, J = 23.2Hz, 3 H) , 0.92 (dq, J = 17.8 Hz, 6 H) .

[0206]
Example 3: preparation of (4S) -3- (2-fluoropropanoyl) -4-isopropyloxazolidin-2-one (5)

[0207]
n-Butyl lithium (2.5 M in hexane, 75 mL, 187 mmol, 1.1eq) was added to a solution of 4- (S) -4-isopropyl-2-oxazolidinone (22 g, 170 mmol, 1 eq) in dry THF (200 mL) at -50 ℃ under N2 atomosphere. After 30 min 2-fuoropropanoyl chloride (17 mL, 153 mmol, 0.9 eq) was added, and the solution was stirred for 1 h at -50 ℃. After the starting material was completely consumed, the reaction was then quenched with a saturated solution of NH4Cl (125 mL) , extracted with MTBE (200 mL *2) , washed with brine and dried over MgSO4. Solvents were removed under reduced pressure. The product was purified over silica (hexane/EtOAc= 10/1) and recovered as a brown oil (34 g, 83.3%) . 1H-NMR (CDCl3, 400 MHz) : δ 5.93 (dm, J = 48.8 Hz, 1 H) , 4.19 -4.17 (m, 3H) , 2.35 (dm, J = 52.8 Hz , 1 H) , 1.55 (td, J = 23.6 Hz, 3 H) , 0.85 (dq, J = 18 Hz, 6 H) .
Example 4: preparation of (4R) -3- (2-fluoropropanoyl) -4-phenyloxazolidin-2-one (6)
n-Butyl lithium (2.5 M in hexane, 13.5 mL, 33.74 mmol, 1.1 eq) was added to a solution of (R) -4-phenyloxazolidin-2-one (5 g, 30.67 mmol, 1 eq) in dry THF (75 mL) at -50 ℃ under N2 atomosphere. After 30 minutes, 2-fuoropropanoyl chloride (3.75 g, 33.74 mmol) was added, and the solution was stirred for 1 h at -50 ℃ to -60 ℃. The reaction was then quenched with a saturated solution of NH4Cl, extracted with EtOAc, washed with NaHCO3(sat) , brine and dried over MgSO4. Solvents were removed under reduced pressure. The product was purified over silica (hexane /EtOAc) and recovered as a brown oil (4 g, 55%) . 1H-NMR (CDCl3, 400 MHz) : δ 7.35-7.21 (m, 5 H) , 5.99-5.84 (md, 1 H) , 5.42-5.33 (dd, 1 H) , 4.72 (dd, 1 H) , 4.31 (m, 1 H) , 1.50 (m, 3 H) .
Example 5: preparation of (4s) -3- (2-fluoropropanoyl) -4-phenyloxazolidin-2-one (7)
n-Butyl lithium (2.5 M in hexane, 67.5 mL, 169 mmol, 1.1 eq) was added to a solution of (s) -4-phenyloxazolidin-2-one (25 g, 153 mmol, 1 eq) in dry THF (375 mL) at -60 ℃ under N2 atomosphere. After 30 min, 2-fuoropropanoyl chloride (18.7 g, 169 mmol) was added, and the solution was stirred for 1h at -50 ℃ to -60 ℃. The reaction was then quenched with a saturated solution of NH4Cl, extracted with EtOAc, washed with NaHCO3 (sat) , brine and dried over MgSO4. Solvents were removed under reduced pressure. The product was purified over silica (hexane /EtOAc) and recovered as a brown oil (16.5 g, 45.4%) . 1H-NMR (CDCl3, 400 MHz) : δ 7.36-7.20 (m, 5 H) , 5.95-5.80 (md, 1 H) , 5.42-5.30 (dd, 1 H) , 4.71 (dd, 1 H) , 4.30 (m, 1 H) , 1.51 (m, 3 H) .
Example 6: preparation of (4S) -4-benzyl-3- (2-fluoropropanoyl) oxazolidin-2-one (8)
n-Butyl lithium (2.5 M in hexane, 54.7 mL, 137 mmol, 1.1eq) was added to a solution of (S) -4-benzyloxazolidin-2-one (22 g, 124 mmol, 1eq) in dry THF (220 mL) at -60 ℃ under N2 atomosphere. After stirring 30 min at -60 ℃, 2-fuoropropanoyl chloride (15.2 g, 137 mmol) was added dropwisely below -50 ℃ , after adding the solution was stirred for 1h at -50 ℃ to -60 ℃. The reaction was then quenched with a saturated solution of NH4Cl, extracted with EtOAc, washed with NaHCO3 (sat) , brine and dried over MgSO4. Solvents were removed under reduced pressure. The product was purified over silica (hexane/EtOAc) and recovered as a brown oil (25.8 g, 82.7%) . 1H-NMR(400 MHz, CDCl3 ) : δ 7.29-7.13 (m, 5 H) , 6.01-5.81 (qd, 1 H) , 4.71-4.58 (md, 1 H) , 4.29-4.04 (m, 2 H) , 3.32-3.16 (dd, 1 H) , 2.79-2.74 (m, 1 H) , 1.51 (m, 3 H) .
Example 7: preparation of (4R) -4-benzyl-3- (2-fluoropropanoyl) oxazolidin-2-one (9)
Use the procedure described in Example 6, (R) -4-benzyloxazolidin-2-one as the start material to give the desired compound (4R) -4-benzyl-3- (2-fluoropropanoyl) oxazolidin-2-one (yield: 85%) . 1H-NMR (400 MHz, CDCl3 ) : δ 7.27 -7.12 (m, 5 H) , 6.00-5.83 (qd, 1 H) , 4.72-4.55 (md, 1 H) , 4.27-4.03 (m, 2 H) , 3.32 -3.16 (dd, 1 H) , 2.79 -2.72 (m, 1 H) , 1.53 (m, 3 H) .

[0221]
Example 8: preparation of (4R) -3- (2-fluoropropanoyl) -4-isopropyl-5, 5-diphenyloxazolidin-2-one (10)

[0222]

[0223]
n-Butyl lithium (2.5 M in hexane, 48 mL) was added to a solution of (R) -4-isopropyl-5,5-diphenyloxazolidin-2-one (28.1 g) in dry THF (150 mL) at -65 ℃ under N2 atomosphere. After stirring 30 min at -60 ℃, 2-fuoropropanoyl chloride (16.4 g, 1.5 eq) was added dropwisely below -60 ℃. After adding the solution was stirred for 2 h at -60 ℃. The reaction was then quenched with a saturated solution of NH4Cl, extracted with EtOAc, washed with NaHCO3 (sat) , brine and dried over MgSO4. Solvents were removed under reduced pressure. The crude product was recrystalized in (DCM/PE) to give (4R) -3- (2-fluoropropanoyl) -4-isopropyl-5, 5-diphenyloxazolidin-2-one (30 g, 85%) . 1H-NMR (CDCl3, 400 MHz) : δ 7.50 -7.26 (m, 10 H) , 5.89 (ddq, J = 64.4, 49.3, 6.6 Hz, 1 H) , 5.37 (dd, J = 70.8, 3.4 Hz, 1 H) , 2.00 (dd, J = 7.3, 3.3 Hz, 1 H) , 1.70 (dd, J = 23.4, 6.7 Hz, 1.5 H) , 1.12 (dd, J = 23.8, 6.6 Hz, 1.5 H) , 0.83 (ddd, J = 28.0, 16.7, 6.9 Hz, 6 H) .

[0224]
Example 9: preparation of (4S) -3- (2-fluoropropanoyl) -4-isopropyl-5, 5-diphenyloxazolidin-2-one (11)

[0225]

[0226]
Use the procedure described in Example 8 and (S) -4-isopropyl-5, 5-diphenyloxazolidin-2-one as the start material to give the desired compound (4S) -3- (2-fluoropropanoyl) -4-isopropyl- 5,5-diphenyl oxazolidin-2-one (yield: 82%) . 1H-NMR (CDCl3, 400 MHz) : δ 7.51 -7.27 (m, 10 H) , 5.90 (ddq, J = 64.4, 49.3, 6.6 Hz, 1 H) , 5.38 (dd, J = 70.8, 3.4 Hz, 1H) , 2.01 (dd, J = 7.3, 3.3 Hz, 1 H) , 1.71 (dd, J = 23.4, 6.7 Hz, 1.5 H) , 1.13 (dd, J = 23.8, 6.6 Hz, 1.5 H) , 0.84 (ddd, J = 28.0, 16.7, 6.9 Hz, 6 H) .

[0227]
Example 10: preparation of (R) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) -4-isopropyloxazolidin-2-one (12)

[0228]

[0229]
Method A: TiCl4 (1 M in DCM, 50 mL, 50 mmol, 1.1 eq) was added to a solution of (4R) -3- (2-fluoropropanoy l ) -4-isopropyloxazolidin-2-one (4) (10 g, 49.2 mmol, 1 eq) in dry DCM (170 mL) at -78 ℃ under N2 atomosphere. After 10 min, diisopropylethyl amine (10.3 mL, 1.26 eq) was added and the solution was stirred for 2 hs at-78 ℃, then the second batch of TiCl4 (1 M in DCM, 50 mL, 50 mmol, 1.1 eq) was added. After 10 min, acrylaldehyde (7 mL, 2 eq) was added and the solution was stirred for 1 h at -78 ℃. Then the reaction was quenched with a saturated solution of NH4Cl (50 mL) . The products were extracted into DCM (20 mL *2) , washed with brine and dried over MgSO4. Solvents were removed under reduced pressure and the product was recrystalized in toluene to give the desired compound as a white solid (10.2 g, yield: 80%, purity: 97.2%) . 1H-NMR (400 MHz, CDCl3) : δ 5.89 (dddd, J = 17.1, 10.5, 6.5, 0.8 Hz, 1 H) , 5.42 (d, J =17.2 Hz, 1 H) , 5.30 (d, J = 10.1 Hz, 1 H) , 4.68 (dd, J = 14.8, 6.5 Hz, 1 H) , 4.44 (d, J = 4.0 Hz, 1 H) , 4.32 (t, J = 8.5 Hz, 1 H) , 4.24 (dd, J = 9.1, 3.4 Hz, 1 H) , 3.61 (d, J = 6.5 Hz, 1 H) , 2.37 (dd, J = 7.0, 4.1 Hz, 1 H) , 1.73 (s, 1.5 H) , 1.67 (s, 1.5 H) , 0.92 (ddd, J = 7.8, 5.6, 2.4 Hz, 6 H) ; 19F-NMR (400 MHz, CDCl3) : -158.3 ppm.

[0230]
Method B: TiCl4 (1 M in DCM, 50 mL, 50mmol, 1.1 eq) was added to a solution of (4R) -3- (2-fluoropropanoy l ) -4-isopropyloxazolidin-2-one (10 g, 49.2 mmol, 1 eq) in dry DCM (170 mL) at -78 ℃ under N2 atomosphere. After 10 min, (-) -spartein (14.5 g, 1.26 eq) was added and the solution was stirred for 2 hs at-78 ℃, then the second batch of TiCl4 (1 M in DCM, 50 mL, 50 mmol, 1.1eq) was added. After 10 min, acrylaldehyde (7 mL, 2 eq) was added and the solution was stirred for 1 h at -78 ℃. Then the reaction was quenched with NH4Cl (sat 50 mL) . The products were extracted into DCM (20 mL *2) , washed with brine and dried over MgSO4. Solvents were removed under reduced pressure and the product was recrystalized in toluene to give the desired compound as a white solid (9.4 g, yield: 75%, purity: 96.5%) .

[0231]
Example 11: preparation of (S) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) -4-isopropyloxazolidin-2-one (13)

[0232]

[0233]
TiCl4 (1 M in DCM, 50 mL, 50 mmol, 1.1 eq) was added to a solution of (4S) -3- (2-fluoropropanoy l ) -4-isopropyloxazolidin-2-one (4) (10 g, 49.2 mmol, 1 eq) in dry DCM (170 mL) at -78 ℃ under N2 atomosphere. After 10 min, diisopropylethyl amine (15.9 g, 2.5 eq) was added and the solution was stirred for 2 hs at-78 ℃. Then acrylaldehyde (7 mL, 2eq) was added and the solution was stirred for 1 h at -78 ℃. Then the reaction was quenched with a saturated solution of NH4Cl (50 mL) . The products were extracted into DCM (20 mL *2) , washed with brine and dried over MgSO4. Solvents were removed under reduced pressure and the product was recrystalized in toluene to give the desired compound as a white solid (10.4 g, yield: 83%, purity: 92.8%) . 1H-NMR (400 MHz, CDCl3) : δ 5.92 (d, J = 1.1 Hz, 1 H) , 5.44 (d, J = 17.2 Hz, 1 H) , 5.34 -5.28 (m, 1 H) , 4.73 (dd, J = 13.9, 6.2 Hz, 1 H) , 4.43 (m, 1 H) , 4.37 -4.30 (m, 1H) , 4.27 -4.21 (m, 1 H) , 2.43 -2.31 (m, 1H) , 1.77 (s, 1.5 H) , 1.71 (s, 1.5 H) , 0.91 (dd, J = 12.1, 7.0 Hz, 6 H) ; 19F-NMR (400 MHz, CDCl3) : δ -159.1ppm.

[0234]
Example 12: preparation of (S) -4-benzyl-3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) oxazolidin-2-one

[0235]

[0236]
TiCl4 (1 M in DCM, 50 mL, 50mmol, 1.1 eq) was added to a solution of (4S) -4-benzyl-3-(2-fluoro propanoyl) oxazolidin-2-one (8) (12.3 g, 49.2 mmol, 1 eq) in dry DCM (170 mL) at -78 ℃ under N2 atomosphere. After 10 min, TMEDA (15.9 g, 2.5 eq) was added and the solution was stirred for 2 hs at -78 ℃. Then acrylaldehyde (7 mL, 2 eq) was added and the solution was stirred for 1 h at -78 ℃. Then the reaction was quenched with a saturated solution of NH4Cl (50 mL) . The products were extracted into DCM (20 mL*2) , washed with brine and dried over MgSO4. Solvents were removed under reduced pressure and the product was recrystalized in toluene to give the desired compound as a white solid (13 g, yield: 86%, purity: 91.5%) . 1H-NMR (400 MHz, CDCl3) : δ 7.38 -7.27 (m, 3 H) , 7.22 (d, J = 6.8 Hz, 2 H) , 5.96 (dddd, J = 17.0, 10.5, 6.2, 1.2 Hz, 1 H) , 5.47 (d, J = 17.2 Hz, 1 H) , 5.35 (d, J = 10.5 Hz, 1 H) , 4.75 (dd, J = 13.9, 6.2 Hz, 1 H) , 4.66 (td, J = 7.1, 3.6 Hz, 1 H) , 4.23 (dd, J = 16.3, 5.0 Hz, 2 H) , 3.33 (dd, J = 13.3, 3.3 Hz, 1 H) , 2.76 (dd, J =13.3, 10.0 Hz, 1 H) , 1.81 (s, 1.5 H) , 1.76 (s, 1.5 H) ; 19F-NMR (400 MHz, CDCl3) : δ -158.47 ppm.

[0237]
Example 13: preparation of (S) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) -4-phenyloxazolidin-2-one

[0238]

[0239]
TiCl4 (1 M in DCM, 50 mL, 50 mmol, 1.1 eq) was added to a solution of (4S) -3- (2-fluoropropanoyl) -4-phenyloxazolidin-2-one (7) (11.6 g, 49.2 mmol, 1 eq) in dry DCM (170 mL) at -78 ℃ under N2 atomosphere. After 10 min, Et3N (12.5 g, 2.5 eq) was added and the solution was stirred for 2 hs at-78 ℃. Then acrylaldehyde (7 mL, 2 eq) was added and the solution was stirred for 1 h at -78 ℃. Then the reaction was quenched with a saturated solution of NH4Cl (50 mL) . The products were extracted into DCM (20 mL *2) , washed with brine and dried over MgSO4. Solvents were removed under reduced pressure and the product was recrystalized in toluene to give the desired compound as a white solid (12 g, yield: 83%, purity: 90.5%) . 1H-NMR (400 MHz, CDCl3) : δ 7.43 -7.30 (m, 5 H) , 5.81 (dddd, J = 17.0, 10.5, 6.3, 1.1 Hz, 1 H) , 5.46 (dd, J = 8.4, 5.1 Hz, 1 H) , 5.37 (dt, J = 17.2, 1.2 Hz, 1 H) , 5.23 (d, J = 10.4 Hz, 1 H) , 4.74 (t, J = 8.7 Hz, 1 H) , 4.64 (dd, J = 13.5, 6.3 Hz, 1 H) , 4.31 (dd, J = 8.9, 5.2 Hz, 1 H) , 1.60 (s, 1.5H) , 1.55 (s, 1.5 H) ; 19F-NMR (400 MHz, CDCl3) : δ -158.47 ppm.

[0240]
Example 14: preparation of (R) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) -4-phenyloxazolidin-2-one

[0241]

[0242]
TiCl4 (1 M in DCM, 50 mL, 50mmol, 1.1 eq) was added to a solution of (4R) -3- (2-fluoro propan oyl) -4-phenyloxazolidin-2-one (6) (11.6 g, 49.2 mmol, 1 eq) in dry DCM (170 mL) at -78 ℃ under N2 atomosphere. After 10 min, DIPEA (15.9 g, 2.5 eq) was added and the solution was stirred for 2 hs at-78 ℃. Then acrylaldehyde (7 mL, 2 eq) was added and the solution was stirred for 1 h at -78℃. Then the reaction was quenched with a saturated solution of NH4Cl (50 mL) . The products were extracted into DCM (20 mL *2) , washed with brine and dried over MgSO4. Solvents were removed under reduced pressure and the product was recrystalized in toluene to give the desired compound as a white solid (11.1 g, yield: 77%, purity: 91.5%) . 1H-NMR (400 MHz, CDCl3) : δ 7.44 -7.29 (m, 5 H) , 5.74 -5.63 (m, 1 H) , 5.48 (dd, J = 8.4, 5.3 Hz, 1 H) , 5.35 -5.26 (m, 1 H) , 5.15 (d, J = 10.5 Hz, 1 H) , 4.73 (t, 1 H) , 4.52 (dd, J = 14.8, 6.2 Hz, 1 H) , 4.28 (dd, J = 8.9, 5.3 Hz, 1 H) , 1.68 (s, 1.5 H) , 1.63 (s, 1.5 H) ; 19F-NMR (400 MHz, CDCl3) : δ -161.93 ppm.

[0243]
Example 15: preparation of (S) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) -4-isopropyl-5, 5-diphenyloxazolidin-2-one

[0244]

[0245]
Method 1: LiHMDS (1 M in THF, 50 mL, 50 mmol, 1.1 eq) was added to a solution of (4S) -3- (2-fluoro propanoyl) -4-isopropyl-5, 5-diphenyloxazolidin-2-one (11) (17.4 g, 49.2 mmol, 1 eq) in dry THF (100 mL) at -20 ℃ under N2 atomosphere. After 1.5 hs, acrylaldehyde (7 mL, 2 eq) was added and the solution was stirred for 1 h at -20 ℃. Then the reaction was quenched with a saturated solution of NH4Cl (50 mL) . The products were extracted into EA (50 mL *2) , washed with brine and dried over MgSO4. Solvents were removed under reduced pressure and the crude product was used directly in the next step. m/z (ES+) : 412 [M+H] +.

[0246]
Method 2: (n-Bu) 2BOTf (1 M in DCM, 50 mL, 50 mmol, 1.1 eq) was added to a solution of (4S) -3- (2-fluoro propanoyl) -4-isopropyl-5, 5-diphenyloxazolidin-2-one (11) (17.4 g, 49.2 mmol, 1 eq) in dry DCM (100 mL) at 0 ℃ under N2 atomosphere. After 15 min, 2, 6-lutidine (10.5g, 2eq) was added and the solution was stirred for 2 hs at 0 ℃. Then acrylaldehyde (7 mL, 2 eq) was added and the solution was stirred for 1 h at 0 ℃. Then the reaction was quenched with a saturated solution of NH4Cl (100 mL) . The products were extracted into DCM (40 mL *2) , washed with brine and dried over MgSO4. Solvents were removed under reduced pressure and the crude product was used directly in the next step (17.82 g, yield: 88% (Internal standard yield) .

[0247]
Method 3: (n-Bu) 2BOTf (1 M in DCM, 50 mL, 50 mmol, 1.1 eq) was added to a solution of (4S) -3- (2-fluoro propanoyl) -4-isopropyl-5, 5-diphenyloxazolidin-2-one (11) (17.4 g, 49.2 mmol, 1 eq) in dry DCM (100 mL) at 0 ℃ under N2 atomosphere. After 15 min, DIPEA (13 g, 2 eq) was added and the solution was stirred for 2 hs at 0 ℃. Then acrylaldehyde (7 mL, 2 eq) was added and the solution was stirred for 1 h at 0 ℃. Then the reaction was quenched with a saturated solution of NH4Cl (100 mL) . The products were extracted into EA (50 mL *2) , washed with brine and dried over MgSO4. Solvents were removed under reduced pressure and the crude product was used directly in the next step (16.2 g, yield: 80% (Internal standard yield ) .

[0248]
Method 4: (C6H122BOTf (1 M in DCM, 50 mL, 50 mmol, 1.1 eq) was added to a solution of (4S) -3- (2-fluoro propanoyl) -4-isopropyl-5, 5-diphenyloxazolidin-2-one (11) (17.4 g, 49.2 mmol, 1 eq) in dry DCM (100 mL) at 0 ℃ under N2 atomosphere. After 15 min, 2, 6-lutidine (10.5 g, 2 eq) was added and the solution was stirred for 2 hs at 0 ℃. Then acrylaldehyde (7 mL, 2 eq) was added and the solution was stirred for 1 h at 0 ℃. Then the reaction was quenched with a saturated solution of NH4Cl (100 mL) . The products were extracted into DCM (50 mL *2) , washed with brine and dried over MgSO4. Solvents were removed under reduced pressure and the crude product was used directly in the next step (14.6 g, yield: 80% (Internal standard yield ) .

[0249]
Example 16: preparation of (3R, 4R, 5R) -3-fluoro-4-hydroxy-5- (hydroxymethyl) -3-methyl dihydro furan-2 (3H) -one

[0250]
Method 1:

[0251]

[0252]
N-Bromosuccinimide (19.6 g, 1.1 eq) was added portionwisely to a solution of (R) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) -4-isopropyloxazolidin-2-one (12) (25.9 g, 100 mmol, 1 eq) in DME/H2O (4: 1, 130ml) at -5 ℃, and stirred for 2 hs . After the reaction was complete, NaHCO3 (sat, 20 mL) was added and stirred for 0.5 h at rt. The mixture were extracted by DCM (50 mL *2) , washed with brine and dried over MgSO4. Solvents were removed, the residue dissolved by MTBE (1V) , the solid was filtered off to recover the auxiliary, the filtrate was concentrated to dryness to obtained the (3R, 4R, 5R) -5- (bromomethyl) -3-fluoro-4-hydroxy-3-methyldihydrofuran-2 (3H) -one (18a) . 1H-NMR (400 MHz, CDCl3) : δ 4.62 -4.53 (m, 1 H) , 4.37 (dd, J = 3.0, 1.9 Hz, 1 H) , 3.73 (dd, J = 10.1, 8.7 Hz, 1 H) , 3.60 (ddd, J = 10.1, 5.8, 1.9 Hz, 1 H) , 2.59 (dd, J = 2.5, 1.7 Hz, 1 H) , 1.67 (d, J = 22.7 Hz, 3 H) ; 19F-NMR (400 MHz, CDCl3) : δ -172.248 ppm.

[0253]
Alternative Method 1a: Br2 (17.6 g, 1.1 eq) was added portionwisely to a solution of (R) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) -4-isopropyloxazolidin-2-one (12) (25.9 g, 100 mmol, 1 eq) in MeCN/H2O (4: 1, 130 mL) between -5 ℃ to -10 ℃ and stirred for 2 hs . After the reaction was complete, Na2S2O3 (10%, 20 ml) was added and stirred for 0.5 h at rt then separated . The water phase was re-extracted by DCM (50 mL *2) , the combine organic phase was concentrated, dissolved by MTBE (1V) , the solid was filtered off to recover the auxiliary, the filtrate was concentrated to dryness to used in the next step.

[0254]
Alternative Method 1b: N-chlorosuccinimide (13.3 g, 1.1 eq) was added portionwisely to a solution of (R) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) -4-isopropyloxazolidin-2-one (12) (25.9 g, 100 mmol, 1 eq) in 100ml CH3CN at -5 ℃, and stirred for 2 hs . After the reaction was complete, NaHCO3 (sat, 20 mL) was added and stirred for 0.5 h at rt. The mixture were extracted by DCM (50 mL *2) , washed with brine and dried over MgSO4. Solvents were removed, the residue dissolved by MTBE (1V) , the solid was filtered off to recover the auxiliary, the filtrate was concentrated to dryness to obtained the (3R, 4R, 5R) -5- (chloromethyl) -3-fluoro-4-hydroxy-3-methyldihydrofuran-2 (3H) -one (18b) , m/z (ES+) : 183 [M+H] +.

[0255]
The related lactone 18a or 18b (0.14eq) was dissolved in EtOH (104 mL) , then KOH (30%in H2O, 50 mL) was added into, the result mixture was reflux for 4 hs. Then HCl (16.7 mL, 12 M) was added into the mixture and reflux for another 2 hs. The solvent was removed and the residue was recrystalized in toluene to give the desired compound as a white solid (yield: 80~85%) . m/z (ES+) : 165 [M+H] +. 1H-NMR (400 MHz, MeOD) : δ 4.34 (ddd, J = 8.0, 4.2, 2.3 Hz, 1 H) , 4.02 (ddd, J = 17.6, 15.2, 5.1 Hz, 2 H) , 3.74 (dd, J = 13.0, 4.2 Hz, 1 H) , 1.60 (s, 1.5 H) , 1.54 (s, 1.5 H) ; 19F-NMR (400 MHz, MeOD) : -172.47 ppm.

[0256]
Method 2:

[0257]

[0258]
Osmium tetroxide (OsO4) (0.1 equiv) was added in one portion to a stirring solution of the (R) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) -4-isopropyloxazolidin-2-one (12) (25.9 g, 100 mmol, 1 eq) in acetone/water (8: 1 ratio) under nitrogen. After 5 min, NMO (N-methylmorpholine N-oxide, 60%by weight in water, 1.1 equiv) was added in one portion and stirred for 24 h. The resulting reaction mixture was concentrated under reduced pressure and immediately purified via column chromatography to obtain the desired lactone (3R, 4R, 5S) -3-fluoro-4-hydroxy-5- (hydroxymethyl) -3-methyldihydrofuran-2 (3H) -one (21) , yield: 87%, m/z (ES+) : 165 [M+H] +.

[0259]
15.1 g (92.3 mmol) (3R, 4R, 5S) -3-fluoro-4-hydroxy-5- (hydroxymethyl) -3-methyl dihydrofuran-2 (3H) -one (21) was dissolved in 25 mL pyridine and 11.1 g (96.9 mmol) methanesulfonyl chloride was slowly added dropwise at -25 degC. It was stirred for a day at -25 deg and a day at -10 deg. After adding 20 mL of ethyl acetate and 20 mL water, the solvent was removed on a rotary evaporator. After neutralization with dilute sodium hydrogen carbonate solution, the solvent was removed in vacuo again, the residue was digested with ethyl acetate, the eluate was dried with magnesium sulfate and concentrated in vacuo to dryness. Recrystallization from ethyl acetate/diethyl ether gave a colorless crystalline product ( (2S, 3R, 4R) -4-fluoro-3-hydroxy-4-methyl-5-oxotetrahydrofuran-2-yl) methyl methanesulfonate (18c) . Yield: 31 %.

[0260]
33.8g of ( (2S, 3R, 4R) -4-fluoro-3-hydroxy-4-methyl-5-oxotetrahydrofuran-2-yl) methyl methanesulfonate was disslolved in EtOH (104 mL) , then KOH (16.8 g , 3 eq) in H2O (52 mL) was added into, the result mixture was reflux for 4 hs. Then HCl (16.7 mL, 12 M) was added into, the mixture was reflux for another 2 hs. The solvent was removed and the residue was recrystalized in toluene to give the desired compound as a white solid (10.5 g, yield: 45%) .

[0261]
Alternative reagents and reactions to those disclosed above can also be employed. For example, 4-methylbenzene-1-sulfonyl chloride can be used instead of methanesulfonyl chloride. Moreover, primary alcohol can be converted to chloro or bromo by using Ph3P/CCl4, PPh3P/CBr4, PPh3/NCS, PPh3/NBS, or PPh3/C2Cl6 as a halogenation reagent. The desired product can be obtained in good yields using these reagents and reactions.

[0262]
Method 3: Using a method analogous to that described as hereinabove and (S) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methyl pent-4-enoyl) -4-isopropyloxazolidin-2-one (13) as starting material provides the desired compound 19 (yield: 63.2%)

[0263]
Method 4: Using a method analogous to that described as hereinabove and (S) -4-benzyl-3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) oxazolidin-2-one (14) as starting material provides the desired compound 19 (yield: 71.8%)

[0264]
Method 5: Using a method analogous to that described as hereinabove and (S) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) -4-phenyloxazolidin-2-one (15) as the start material gives the desired compound 19 (yield: 65.7%)

[0265]
Method 6: Using a method analogous to that described as hereinabove and (R) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) -4-phenyloxazolidin-2-oneas (16) starting material provides the desired compound 19 (yield: 59.5%)

[0266]
Method 7: Using a method analogous to that described as hereinabove and (S) -3- ( (2R, 3R) -2-fluoro-3-hydroxy-2-methylpent-4-enoyl) -4-isopropyl-5, 5-diphenyloxazolidin-2-one (17) as starting material gives the desired compound 19 (yield: 66.7%)

[0267]
Example 17: preparation of ( (3R, 4R) -3- (benzoyloxy) -4-fluoro-4-methyl-5-oxotetra hydro fur an-2-yl) methyl benzoate

[0268]

[0269]
(3R, 4R) -3-fluoro-4-hydroxy-5- (hydroxymethyl) -3-methyldihydrofuran-2 (3H) -one (19) (25.4 g, 0.154 mol) obtained from example 3 was dissolved in 200 ml of THF. 4- (Dimethylamino) -pyridine (8.2 g, 0.066 mol) and triethylamine (35 g, 0.35 mol) were added and the reaction mixture was cooled to 0 ℃. Benzoyl chloride (46.0 g, 0.33 mol) was added, and the mixture was warmed to 35-40 ℃ in the course of 2 hs. Upon completion of the reaction, water (100 mL) was charged and the mixture was stirred for 30 min. Phases were separated and to the aqueous phase methyl-tert-butyl ether (100 mL) was added and the mixture was stirred for 30 min. Phases were separated and the organic phase was washed with saturated NaCl solution (100 mL) . The combined organic phases were dried over Na2SO4 (20 g) filtered and the filtrate was evaporated to dryness. The residue was taken up in iso-propanol (250 mL) and the mixture was warmed to 50 ℃ and stirred for 60 min, then cooled down to 0 ℃ and further stirred for 60 min. The solid was filtered and the wet cake was washed with i-propanol (50 mL) and then dried under vacuum. The title compound ( (3R, 4R) -3- (benzoyloxy) -4-fluoro-4-methyl-5-oxotetrahydrofuran-2-yl) methyl benzoate (47.5 g, 82.6 %yield) was obtained. ‘H-NMR (CDCl3, 400 MHz) : 8.10 (d, 7=7.6 Hz, 2H) , 8.00 (d, 7=7.6 Hz, 2H) , 7.66 (t, 7=7.6 Hz, IH) , 7.59 (t, 7=7.6 Hz, IH) , 7.50 (m, 2H) , 7.43 (m, 2H) , 5.53 (dd, 7=17.6, 5.6 Hz, IH) , 5.02 (m, IH) , 4.77 (dd, 7=12.8, 3.6 Hz, IH) , 4.62 (dd, 7=12.8, 5.2 Hz, IH) , 1.77 (d, 7=23.2 Hz, 3H) .

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BICTEGRAVIR, NEW PATENT, WO 2018005328, CONCERT PHARMA


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BICTEGRAVIR, NEW PATENT, WO 2018005328, CONCERT PHARMA

WO2018005328) DEUTERATED BICTEGRAVIR 

CONCERT PHARMACEUTICALS, INC.

TUNG, Roger, D.; (US)

How A Kidney Drug Almost Torpedoed Concert Pharma’s IPO

Concert CEO Roger Tung

Novel deuterated forms of bictegravir is claimed.  Gilead Sciences is developing the integrase inhibitor bictegravir as an oral tablet for the treatment of HIV-1 infection.

This invention relates to deuterated forms of bictegravir, and pharmaceutically acceptable salts thereof. In one aspect, the invention provides a compound of Formula (I) or a pharmaceutically acceptable salt thereof, wherein each of Y1, Y2, Y3, Y4a, Y4b, Y5a, Y5b, Y6, Y7a, Y7b, Y8, Y9, Y10a, Y10b, Y11a, and Y11b is independently hydrogen or deuterium; provided that if each Y1, Y2, Y3, Y4a, Y4b, Y5a, Y5b, Y6, Y7a, Y7b, Y8, Y9, Y10a, Y10b, and Y11 is hydrogen, then Y11b is deuterium.

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Many current medicines suffer from poor absorption, distribution, metabolism and/or excretion (ADME) properties that prevent their wider use or limit their use in certain indications. Poor ADME properties are also a major reason for the failure of drug candidates in clinical trials. While formulation technologies and prodrug strategies can be employed in some cases to improve certain ADME properties, these approaches often fail to address the underlying ADME problems that exist for many drugs and drug candidates. One such problem is rapid metabolism that causes a number of drugs, which otherwise would be highly effective in treating a disease, to be cleared too rapidly from the body. A possible solution to rapid drug clearance is frequent or high dosing to attain a sufficiently high plasma level of drug. This, however, introduces a number of potential treatment problems such as poor patient compliance with the dosing regimen, side effects that become more acute with higher doses, and increased cost of treatment. A rapidly metabolized drug may also expose patients to undesirable toxic or reactive metabolites.

[3] Another ADME limitation that affects many medicines is the formation of toxic or biologically reactive metabolites. As a result, some patients receiving the drug may experience toxicities, or the safe dosing of such drugs may be limited such that patients receive a suboptimal amount of the active agent. In certain cases, modifying dosing intervals or formulation approaches can help to reduce clinical adverse effects, but often the formation of such undesirable metabolites is intrinsic to the metabolism of the compound.

[4] In some select cases, a metabolic inhibitor will be co-administered with a drug that is cleared too rapidly. Such is the case with the protease inhibitor class of drugs that are used to treat HIV infection. The FDA recommends that these drugs be co-dosed with ritonavir, an inhibitor of cytochrome P450 enzyme 3A4 (CYP3A4), the enzyme typically responsible for their metabolism (see Kempf, D.J. et al., Antimicrobial agents and chemotherapy, 1997, 41(3): 654-60). Ritonavir, however, causes adverse effects and adds to the pill burden for HIV patients who must already take a combination of different drugs. Similarly, the

CYP2D6 inhibitor quinidine has been added to dextromethorphan for the purpose of reducing rapid CYP2D6 metabolism of dextromethorphan in a treatment of pseudobulbar affect. Quinidine, however, has unwanted side effects that greatly limit its use in potential combination therapy (see Wang, L et al., Clinical Pharmacology and Therapeutics, 1994, 56(6 Pt 1): 659-67; and FDA label for quinidine at http://www.accessdata.fda.gov).

[5] In general, combining drugs with cytochrome P450 inhibitors is not a satisfactory strategy for decreasing drug clearance. The inhibition of a CYP enzyme’s activity can affect the metabolism and clearance of other drugs metabolized by that same enzyme. CYP inhibition can cause other drugs to accumulate in the body to toxic levels.

[6] A potentially attractive strategy for improving a drug’s metabolic properties is deuterium modification. In this approach, one attempts to slow the CYP-mediated metabolism of a drug or to reduce the formation of undesirable metabolites by replacing one or more hydrogen atoms with deuterium atoms. Deuterium is a safe, stable, non-radioactive isotope of hydrogen. Compared to hydrogen, deuterium forms stronger bonds with carbon. In select cases, the increased bond strength imparted by deuterium can positively impact the ADME properties of a drug, creating the potential for improved drug efficacy, safety, and/or tolerability. At the same time, because the size and shape of deuterium are essentially identical to those of hydrogen, replacement of hydrogen by deuterium would not be expected to affect the biochemical potency and selectivity of the drug as compared to the original chemical entity that contains only hydrogen.

[7] Over the past 35 years, the effects of deuterium substitution on the rate of metabolism have been reported for a very small percentage of approved drugs (see, e.g., Blake, MI et al, J Pharm Sci, 1975, 64:367-91; Foster, AB, Adv Drug Res 1985, 14:1-40 (“Foster”); Kushner, DJ et al, Can J Physiol Pharmacol 1999, 79-88; Fisher, MB et al, Curr Opin Drug Discov Devel, 2006, 9:101-09 (“Fisher”)). The results have been variable and unpredictable. For some compounds deuteration caused decreased metabolic clearance in vivo. For others, there was no change in metabolism. Still others demonstrated increased metabolic clearance. The variability in deuterium effects has also led experts to question or dismiss deuterium modification as a viable drug design strategy for inhibiting adverse metabolism (see Foster at p.35 and Fisher at p.101).

[8] The effects of deuterium modification on a drug’s metabolic properties are not predictable even when deuterium atoms are incorporated at known sites of metabolism. Only by actually preparing and testing a deuterated drug can one determine if and how the rate of metabolism will differ from that of its non-deuterated counterpart. See, for example, Fukuto et al. (J. Med. Chem.1991, 34, 2871-76). Many drugs have multiple sites where metabolism is possible. The site(s) where deuterium substitution is required and the extent of deuteration necessary to see an effect on metabolism, if any, will be different for each drug.

Exemplary Synthesis

[72] Deuterium-modified analogs of bictegravir can be synthesized by means known in the art of organic chemistry. For instance, using methods described in US Patent No.9,216,996 (Haolun J. et al., assigned to Gilead Sciences, Inc. and incorporated herein by reference), using deuterium-containing reagents provides the desired deuterated analogs.

[73] Such methods can be carried out utilizing corresponding deuterated and optionally, other isotope-containing reagents and/or intermediates to synthesize the compounds delineated herein, or invoking standard synthetic protocols known in the art for introducing isotopic atoms to a chemical structure.

[74] A convenient method for synthesizing compounds of Formula I is depicted in the Schemes below.

 [75] A generic scheme for the synthesis of compounds of Formula I is shown in Scheme 1 above. In a manner analogous to the procedure described in Wang, H. et al. Org. Lett.2015, 17, 564-567, aldol condensation of compound 1 with appropriately deuterated compound 2 affords enamine 3. Enamine 3 is then reacted with primary amine 4 to afford enamine 5, which then undergoes cyclization with dimethyl oxalate followed by ester hydrolysis to provide carboxylic acid 7.

[76] In a manner analogous to the procedure described in US 9,216,996, acetal deprotection of carboxylic acid 7 followed by cyclization with appropriately deuterated aminocyclopentanol 9 provides carboxylic acid intermediate 10. Amide coupling with appropriately deuterated benzylamine 11 followed by deprotection of the methyl ether ultimately affords a compound of Formula I in eight overall steps from compound 1.

[77] Use of appropriately deuterated reagents allows deuterium incorporation at the Y1, Y2, Y3, Y4a, Y4b, Y5a, Y5b, Y6, Y7a, Y7b, Y8, Y9, Y10a, Y10b, Y11a, and Y11bpositions of a compound of Formula I or any appropriate intermediate herein, e.g., about 90%, about 95%, about 97%, about 98%, or about 99% deuterium incorporation at any Y1, Y2, Y3, Y4a, Y4b, Y5a, Y5b, Y6, Y7a, Y7b, Y8, Y9, Y10a, Y10b, Y11a, and/or Y11b.

[78] Appropriately deuterated intermediates 2a and 2b, for use in the preparation of compounds of Formula I according to Scheme 1, may be prepared from corresponding deuterated reagents as exemplified in Scheme 2 below.

S h 2 S th i f C d 2 d 2b

[79] Synthesis of compound 2a (wherein Y3=H) by acetal formation of N,N-dimethylformamide (DMF) with dimethylsulfate has been described in Mesnard, D. et. al. J. Organomet. Chem.1989, 373, 1-10. Replacing DMF with N,N-dimethylformamide-d1 (98-99 atom % D; commercially available from Cambridge Isotope Laboratories) in this reaction would thereby provide compound 2b (wherein Y3=D).

[80] Use of appropriately deuterated reagents allows deuterium incorporation at the Y3 position of a compound of Formula I or any appropriate intermediate herein, e.g., about 90%, about 95%, about 97%, about 98%, or about 99% deuterium incorporation at Y3.

[81] Appropriately deuterated intermediates 4a-4d, for use in the preparation of compounds of Formula I according to Scheme 1, may be prepared from corresponding deuterated reagents as exemplified in Scheme 3 below.

[82] As described in Malik, M. S. et. al. Org. Prep. Proc. Int.1991, 26, 764-766, acetaldehyde is converted to alkylhalide 14a via reaction with chlorine gas and subsequent acetal protection with CaCl2 in methanol. As described in CN 103739506, reaction of 14a with aqueous ammonia and then sodium hydroxide provides primary amine 4a (wherein Y9=Y10a=Y10b=H). Replacing acetaldehyde with acetaldehyde-d1, acetaldehyde-2,2,2-d3, or acetaldehyde-d4 (all commercially available from CDN Isotopes with 98-99 atom % D) in the sequence then provides access to compounds 4b (Y9=D, Y10a=Y10b=H), 4c (Y9=H,

Y10a=Y10b=D) and 4d (Y9=Y10a=Y10b=D) respectively (Schemes 3b-d).

[83] Use of appropriately deuterated reagents allows deuterium incorporation at the Y9, Y10a, and Y10b positions of a compound of Formula I or any appropriate intermediate herein, e.g., about 90%, about 95%, about 97%, about 98%, or about 99% deuterium incorporation at any Y9, Y10a, and/or Y10b.

[84] Appropriately deuterated intermediates 9a-9d, for use in the preparation of compounds of Formula I according to Scheme 1, may be prepared from corresponding deuterated reagents as exemplified in Scheme 4 below.

 [85] Following the procedures described by Gurjar, M. et. al. Heterocycles, 2009, 77, 909-925, meso-diacetate 16a is prepared in 2 steps from cyclopentadiene. Desymmetrization of 16a is then achieved enzymatically by treatment with Lipase as described in Specklin, S. et. al. Tet. Lett.201455, 6987-6991, providing 17a which is subsequently converted to aminocyclopentanol 9a (wherein Y4a=Y4b=Y5a=Y5b=Y6=Y7a=Y7b=Y8=H) via a 3 step sequence as reported in WO 2015195656.

[86] As depicted in Scheme 4b, aminocyclopentanol 9b (Y4a=Y4b=Y5a=Y5b=Y6=Y7a=Y7b= Y8=D) is obtained through an analogous synthetic sequence using cyclopentadiene-d6 and performing the penultimate hydrogenation with D2 in place of H2. Cyclopentadiene-d6 is prepared according to the procedure described in Cangoenuel, A. et. al. Inorg. Chem.2013, 52, 11859-11866.

[87] Alternatively, as shown in Scheme 4c, the meso-diol obtained in Scheme 4a is oxidized to the diketone following the procedure reported by Rasmusson, G.H. et. al. Org. Syn.1962, 42, 36-38. Subsequent mono-reduction with sodium borodeuteride and CeCl3 then affords the D1-alcohol in analogy to the method described in WO 2001044254 for the all-protio analog using sodium borohydride. Reduction of the remaining ketone using similar conditions provides the meso-D2-diol in analogy to the method reported in Specklin, S. et. al. Tet. Lett.2014, 55, 6987-6991 for the all protio analog using sodium borohydride. The meso-D2-diol is then converted to 9c (Y4a=Y4b=Y5a=Y5b=Y7a=Y7b=H, Y6=Y8=D) following the same procedures outlined in Scheme 4a.

[88] Likewise, the meso-diol obtained in Scheme 4b may be converted to 9d

(Y4a=Y4b=Y5a=Y5b=Y7a=Y7b=D, Y6=Y8=H) in an analogous manner as depicted in Scheme 4d. The use of deuterated solvents such as D2O or MeOD may be considered to reduce the risk of D to H exchange for ketone containing intermediates.

[89] Use of appropriately deuterated reagents allows deuterium incorporation at the Y4a, Y4b, Y5a, Y5b, Y6, Y7a, Y7b, and Y8 positions of a compound of Formula I or any appropriate intermediate herein, e.g., about 90%, about 95%, about 97%, about 98%, or about 99% deuterium incorporation at any Y4a, Y4b, Y5a, Y5b, Y6, Y7a, Y7b, and/or Y8.

[90] Appropriately deuterated intermediates 11a-11d, for use in the preparation of compounds of Formula I according to Scheme 1, may be prepared from corresponding deuterated reagents exemplified in Scheme 5 below.

Scheme 5. Synthesis of Benzylamines 11a-11d

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WO-2018001353, APREMILAST, NEW PATENT, ZHEJIANG HUAHAI PHARMACEUTICAL CO., LTD


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WO-2018001353, APREMILAST, NEW PATENT, ZHEJIANG HUAHAI PHARMACEUTICAL CO., LTD

 (WO2018001353) METHOD FOR PREPARING APREMILAST

ZHEJIANG HUAHAI PHARMACEUTICAL CO., LTD

DU, Xiaoqiu; (CN).
ZHOU, Lianchao; (CN).
LIU, Jiegen; (CN)

https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2018001353&recNum=1&maxRec=&office=&prevFilter=&sortOption=&queryString=&tab=FullText

EN)Method one: (S) -1- (3-ethoxy-4-methoxyphenyl) -2- (methylsulfonyl) ethylamine N-acetyl-L-leucine salt of formula II is reacted with 3-acetylaminophthalic anhydride of formula III in an aprotic solvent to produce the compound of formula I; method two: (S) -1- (3-ethoxy-4-methoxyphenyl) -2- (methylsulfonyl) ethylamine N-acetyl-L- leucine salt of formula II is reacted with 3-acetylaminophthalic anhydride of formula III in an organic solvent in the presence of an organic alkaline or an alkali metal hydride to produce the compound of formula I. The method for preparing apremilast requires inexpensive raw materials and reagents , is suitable for industrialized production, and has great economic effects.

Apremilast is a PDE4 inhibitor developed by Celgene. Currently, there are clinical indications such as rheumatoid arthritis, psoriatic arthritis, Behcet’s disease and ulcerative colitis. March 21, 2014 FDA approves first indication – adult active psoriatic arthritis (PsA). Name of Product: (FDA, as a post-marketing requirement, will evaluate the effect of this drug on pregnant women through a pregnancy registry study.) Three clinical trials evaluated the safety and efficacy of Asprate in the treatment of PsA, The response rates to ACR20 in the prest and placebo groups were 32-41% and 18-19%, respectively.
Aspast’s oral anti-rheumatic drug, a new mechanism of action, distinguishes itself from currently available anti-TNF monoclonal antibodies. Thomson Pharma predicts rapid sales growth of 201.2 million U.S. dollars in 2015 with sales of US $ 516 million in 2015 . Upstall’s sales are expected to reach a maximum of 2 billion U.S. dollars. Compared with its counterparts, Actuate has the following advantages: It inhibits the production of various proinflammatory mediators (PDE-4, TNF-α, IL-2, interferon γ, leukotriene, NO synthase) Inflammation; selective inhibitor of phosphodiesterase 4 (PDE4), approved for use in psoriatic arthritis in September 2014 FDA approved mid-to-severe treatment of plaque psoriasis for phototherapy or systemic therapy Patient, the first and only PDE4 inhibitor approved for the treatment of plaque psoriasis; clinical trials have shown that OTEZLA reduces erythema, thickening and scaling in patients with moderate to severe plaque psoriasis; clinical trials have demonstrated Painstrept was well tolerated and had minimal adverse reactions. Patients in the Otezla-treated and placebo clinical trials showed signs and symptoms of PsA improvement including tenderness, joint swelling and physical function.
The original patent CN 101683334A reports the synthesis of (S) -1- (3-ethoxy-4-methoxyphenyl) -2- (methylsulfonyl) ethylamine N-acetyl- ) And 3-acetylaminophthalic anhydride (3) Prepared with acetic acid as solvent (1), and the synthetic route is as follows:
The method has low yield, needs lower than 50 DEG C to distill the high-boiling acetic acid, and produces one deacetyl impurity (4) during the reflux reaction and the acetic acid distillation, which affects the product purity. Acetic acid will corrode the equipment at high temperatures. Distillation of high-boiling acetic acid will also increase plant production time. Acetic acid, which is not distilled away, consumes a large amount of lye to neutralize and increases the amount of wastes and production costs, which is not conducive to industrialized production.
Example one
10.0 g (0.0224 mol) of (S) -1- (3-ethoxy-4-methoxyphenyl) -2- (methylsulfonyl) ethylamine N-acetyl- 4.6g (0.0224mol) 3-acetamidophthalic anhydride into a 250mL three-necked flask, then add 50mL of acetonitrile, heating 75 ~ 80 ℃, the reaction incubated for 18 hours and cooled to room temperature. After the reaction mixture was evaporated to dryness, 60 mL of methylene chloride was added, 25 g of 10% sodium carbonate solution was added thereto and the mixture was stirred for 10 to 30 minutes. The mixture was allowed to stand for further delamination and then 25 mL of water was added to the organic layer and stirred for 10-30 minutes. The layers were evaporated to dryness to give a light yellow solid, then add 30mL absolute ethanol, evaporated again. The mixture was hot beaten with ethanol, cooled to 0-5 ° C, stirred for 1-2 hours, filtered and drained. The filter cake was vacuum dried to give 9.4 g of a white powder in 91.2% yield. HPLC: 99.9% ) Has an HPLC area of 0.03%.
Example two
10.0 g (0.0224 mol) of (S) -1- (3-ethoxy-4-methoxyphenyl) -2- (methylsulfonyl) ethylamine N-acetyl- A solution of 4.6 g (0.0224 mol) of 3-acetylaminophthalic anhydride in a 250 mL three-necked flask was charged with 80 mL of toluene and 10 mL of N, N-dimethylformamide. The mixture was heated to 100 ° C and the reaction was incubated for 12 hours and then cooled to room temperature. After the reaction solution was evaporated to dryness, 80 mL of methylene chloride was added, 25 g of 10% sodium carbonate solution was added thereto and the mixture was stirred for 10 to 30 minutes. The mixture was allowed to stand for further delamination and then 50 mL of water was added to the organic layer and stirred for 10 to 30 minutes. Evaporated to a pale yellow solid, then add 30mL of absolute ethanol, evaporated again. Cooled to 0 ~ 5 ℃ and stirred for 1 ~ 2 hours, filtered and drained, the filter cake was dried in vacuo to give 9.2g white powder, yield 89.2%, HPLC: 99.9%, wherein the deacetyl impurities (4 ) Has an HPLC area of 0.03%.
Example three:
10.0 g (0.0224 mol) of (S) -1- (3-ethoxy-4-methoxyphenyl) -2- (methylsulfonyl) ethylamine N-acetyl- To a 250 mL three-necked flask was added 4.6 g (0.0224 mol) of 3-acetamidophthalic anhydride followed by 50 mL of ethyl acetate and 1.81 g (0.8 eq) of triethylamine. The mixture was heated at 75-80 ° C and incubated for 18 hours. The reaction was stopped, 100 mL of ethyl acetate was further added and the mixture was cooled to 20-30 ° C. The reaction solution was added 30g of 8% sodium carbonate solution, stirred for 10 to 30 minutes, allowed to stand layered, the organic layer was added 30mL of water, stirred for 10 to 30 minutes, allowed to stand layered, the organic layer was added 30mL of water, stirred 10 ~ 30 minutes, standing stratification, the organic layer was evaporated to dryness to a pale yellow solid, then add 30mL of absolute ethanol, evaporated again. The mixture was heated to 0-5 ° C for 1 to 2 hours, filtered and drained. The filter cake was vacuum dried to give 9.8 g of a white powder in 95.1% yield. HPLC: 99.9% ) Had an HPLC area of 0.04%.
Example 4:
10.0 g (0.0224 mol) of (S) -1- (3-ethoxy-4-methoxyphenyl) -2- (methylsulfonyl) ethylamine N-acetyl- (0.0224mol) 3-acetamidophthalic anhydride into a 250mL three-necked flask, followed by the addition of 120mL of isopropyl acetate and 30mL of acetonitrile and 1.81g (0.8eq) of triethylamine, heating 75 ~ 80 ℃, incubated reaction 16 hours. Stop the reaction, cooled to 20 ~ 30 ℃. The reaction solution was added 30g of 8% sodium carbonate solution, stirred for 10 to 30 minutes, allowed to stand layered, the organic layer was added 30mL of water, stirred for 10 to 30 minutes, allowed to stand layered, the organic layer was added 30mL of water, stirred 10 ~ 30 minutes, standing stratification, the organic layer was evaporated to dryness to a pale yellow solid, then add 30mL of absolute ethanol, evaporated again. The mixture was hot beaten with ethanol, cooled to 0-5 ° C, stirred for 1-2 hours, filtered and drained. The filter cake was vacuum dried to give 9.6 g of a white powder in 93.1% yield. HPLC: 99.9% ) Has an HPLC area of 0.03%.
Comparative Example:
According to the preparation example of Compound A in original patent CN 101683334A, 10.0 g (0.0224 mol) of (S) -1- (3-ethoxy-4- methoxyphenyl) -2- (methylsulfonyl) N-acetyl-L-leucinate and 4.6 g (0.0224 mol) of 3-acetylaminophthalic anhydride were placed in a 250 mL three-necked flask and 50 mL of acetic acid was added thereto. The mixture was heated at 75 to 80 ° C and the reaction was incubated for 18 hours. The reaction mixture was cooled to 40-50 ° C and the temperature of the water bath was controlled to 40-50 ° C. The reaction mixture was vortexed to glacial acetic acid without any significant fraction. 150 mL of ethyl acetate was added and the mixture was stirred to dissolve. 100 mL of water was added and the mixture was stirred 10 ~ 30 minutes, standing stratification, the organic layer was added 100mL water, stirred for 10 to 30 minutes, allowed to stand for stratification, the organic layer was added 100g 8% sodium bicarbonate solution, stirred for 10 to 30 minutes, The organic layer was added with 100g of 8% sodium bicarbonate solution and stirred for 10-30 minutes. The layers were separated and the organic layer was added with 100 mL of water. The mixture was stirred for 10-30 minutes, and the layers were separated. The organic layer was further added with 100 mL of water and stirred 10 ~ 30 minutes, standing stratification, the organic layer was evaporated to dryness to a pale yellow solid, then add 30mL of absolute ethanol, evaporated again. 68mL of anhydrous ethanol and 34mL of acetone were added to the solid, heated to 60-65 ° C, stirred to make it fully dissolved, and then cooled to 0-5 ° C and stirred for 1 to 2 hours, filtered and drained, and the filter cake was dried under vacuum to give 8.6 Class g white powder, yield 83.4%, HPLC: 99.7% with an HPLC area of deacetylated impurity (4) of 0.22%.

////////////WO 2018001353, APREMILAST, NEW PATENT, ZHEJIANG HUAHAI PHARMACEUTICAL CO., LTD

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Pexidartinib, New Patent, WO 2017215521, Crystal Pharmatech Co Ltd


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Pexidartinib, New Patent, WO, 2017215521, Crystal Pharmatech Co Ltd

(WO2017215521) PLX3397 HYDROCHLORIDE CRYSTAL FORM, PREPARATION METHOD THEREFOR AND USE THEREOF

https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2017215521

CRYSTAL PHARMACEUTICAL (SUZHOU) CO., LTD

INVENTORS

CHEN, Minhua; (CN).
ZHANG, Yanfeng; (CN).
ZOU, Po; (CN).
ZHANG, Xiaoyu; (CN)

Novel crystalline forms of PLX3397 hydrochloride (designated as Forms CS2 and CS3), processes for their preparation and compositions comprising them are claimed. Also claim is their use for treating giant cell tumor of the tendon sheath.

The present invention relates to a PLX3397 hydrochloride crystal form, a preparation method therefor and use thereof. The PLX3397 hydrochloride crystal form has higher solubility, larger particle size, and good stability, especially better mechanical stability, is favorable for separation of products in subsequent production, provides a better choice for preparing PLX3397-containing pharmaceutical preparations, and is very important to medicinal development.

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Pexidartinib (PLX3397) is a new drug used to treat tenosynovial giant cell tumor (TGCT). Tenoid sheath giant cell tumor is a rare type of tendon sheath cancer. At present, the disease is usually treated surgically by surgical resection, and the surgical treatment of the disease may lead to the deterioration of dysfunction and serious complications. And since TGCTs have multiple types, which typically occur at bone tissue and joints, the advent of new interventional therapies is urgently needed in the clinic. The PLX3397 is currently in Phase III clinical trials and has received the FDA’s breakthrough drug therapy certification. The structural formula of PLX3397 is shown in formula (I).
Example 1 Preparation of monohydrochloride form CS2

[0112]
Weigh 101.6 mg of PLX3397 solids in a 5 mL glass vial and add 2 mL of n-heptane at 5 ° C. Under magnetic stirring, 440 μL of 0.6 mol / L diluted hydrochloric acid was added and the reaction was carried out for 40 min. The mixture was filtered and dried to obtain an off-white solid.

[0113]
Upon testing, the solid obtained in this example is the monohydrochloride form CS2. The XRPD pattern is shown in Figure 1, and the XRPD data is shown in Table 1. The resulting solid was monohydrochloride salt of PLX3397 as determined by ion chromatography. 1 H NMR is shown in FIG. 4.

[0114]
When differential scanning calorimetry was used, the endothermic peak began to form when heated to about 72 ° C. When heated to around 227 ° C, the endothermic peak started to appear. The DSC is shown in FIG. 2.

[0115]
When subjected to thermogravimetric analysis, crystalline form CS2 has a mass loss gradient of about 8.3% when heated to 137 ° C, the TGA of which is shown in FIG. 3. Form CS2 is hydrate.

[Figure 0009]   

Fig. 1 H NMR chart of crystalline form CS3 in Example 3. Fig

//////////////Pexidartinib, New Patent, WO 2017215521, Crystal Pharmatech Co Ltd

ALCAFTADINE, WO 2017211246, NEW PATENT, SHENZHEN TARGETRX, INC.


Alcaftadine.svg

Alcaftadine

NEW PATENT

https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2017211246&redirectedID=true

WO-2017211246, SHENZHEN TARGETRX, INC.

SUBSTITUTED FUSED IMIDAZOLE CYCLIC COMPOUND AND PHARMACEUTICAL COMPOSITION THEREOF

WANG, Yihan; (CN).
XING, Qingfeng; (CN)

Novel deuterated analogs of substituted fused imidazole cyclic compounds, particularly alcaftadine are histamine H1-receptor antagonists and mast cell stabilizers, useful for treating allergy and nasal congestion.

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The present invention relates to a substituted fused imidazole cyclic compound and a composition containing said compound and application thereof. Specifically disclosed is the fused imidazole cyclic compound represented by formula (I), or a pharmaceutical composition of its crystalline form, pharmaceutically acceptable salt, prodrug, stereoisomer, hydrate, or solvate. The compound of the present invention may be used as a histamine H1-receptor antagonist and mast-cell stabilizer, and is capable of inhibiting mast-cell release of histamine and preventing histamine function, thereby reducing allergic reaction

str2

Example 1 Preparation of 6,11-dihydro -11- (1- (d3- methyl) piperidin-4-ylidene) -5H- imidazo [2,1-b] [3] benzazepine – 3- aldehyde (compound 8)

Step 1. Synthesis of compound 3.

N-benzyloxycarbonylpiperidine-4-carboxylic acid (2.63 g, 10 mmol) was dissolved in 20 mL of dichloromethane, 6 mL of oxalyl chloride and 1 drop of DMF were added and the mixture was reacted at room temperature for 2 hours under nitrogen. The reaction mixture was concentrated to dryness under reduced pressure, dissolved in 20 mL of acetonitrile, and added with triethylamine (4.1 mL, 30 mmol) in an ice bath and stirred for 3 minutes. A solution of 1-phenethyl-1H-imidazole (2.06 g, 12 mmol) in 5 mL of acetonitrile was slowly added dropwise and the reaction was allowed to warm to room temperature overnight after the addition was completed. The reaction was completed, concentrated to dryness, 30 mL of ethyl acetate and 20 mL of water were added and the mixture was stirred for 5 minutes. The layers were separated and the aqueous phase was extracted with ethyl acetate. The combined organic phases were dried over anhydrous sodium sulfate and concentrated to give 3.34 g of a colorless oil, benzyl-4- (1-phenethyl-1H-imidazole-2-formyl) piperidine-1-carboxylate (Compound 3) was obtained in a yield of 80%. ESI-MS: 418 [M ++ 1].

Step 2. Synthesis of compound 4.
Benzyl-4- (1-phenylethyl-1H-imidazole-2-formyl) piperidine-1-carboxylate (3.34 g, 8 mmol) was dissolved in 30 mL of absolute ethanol and 300 mg of 10% palladium on carbon , Hydrogen was substituted three times and stirred overnight at room temperature under a hydrogen atmosphere of 1 atmosphere. After completion of the reaction, the palladium carbon was filtered off and the filtrate was concentrated. 2.04 g of (1-phenethyl-1H-imidazol-2-yl) (piperidin-4-yl) methanone (Compound 4) 90%. ESI-MS: 284 [M ++ 1].
Step 3. Synthesis of compound 5.
(Piperidin-4-yl) methanone (2.04 g, 7.2 mmol) was dissolved in 10 mL of DMF and potassium carbonate (1.98 g, 14.4 mmol) The solution was cooled to -15 ° C and deuterated methyl iodide (1.02 g, 7.2 mmol) was slowly added dropwise under the protection of nitrogen. After the addition was completed, the mixture was stirred at room temperature for 0.5 hour. The mixture was extracted with ethyl acetate and extracted with ethyl acetate. The organic phase was washed once with 20 mL of water and 20 mL of saturated brine, dried over anhydrous sodium sulfate, concentrated and separated on a silica gel column (1- (methyl-d3) piperidine (1-phenethyl-1H-imidazol-2-yl) methanone (Compound 5) was obtained in an amount of 70%. 1 H NMR (300 MHz, CDCl 3 ) δ 7.23 (d, J = 2.0Hz, 1H), 7.06 (td, J = 4.2,3.8,1.7Hz, 3H), 6.86 (d, J = 1.0Hz, 1H) (Dd, J = 10.2, 5.8 Hz, 2H), 3.09 (t, J = 7.2 Hz, 2H) J = 7.2 Hz, 2H), 2.85-2.65 (m, 2H), 2.15 (td, J = 7.5, 3.9 Hz, 4H); ESI-MS: 301 [M ++ l ].
Step 4. Synthesis of Compound 6.
(1-phenethyl-1H-imidazol-2-yl) methanone (1.5 g, 5.1 mmol) was placed in a reaction flask and the mixture was purged with nitrogen three times , 7mL trifluoromethanesulfonic acid was added dropwise, the reaction was warmed to 110 ° C overnight. Cooled to room temperature, the reaction solution was poured into 30mL ice water, 50% sodium hydroxide solution was added dropwise to adjust the pH = 10-11, extracted with dichloromethane, the organic phase was washed once with 20mL of water and 20mL of saturated brine, Dried over sodium sulfate, concentrated and separated by silica gel column to obtain 0.85 g of compound 6, yield 60%. 1 H NMR (300 MHz, CDCl 3 ) δ 7.28 (d, J = 4.4 Hz, 2H), 7.23 (d, J = 5.0 Hz, 1H), 7.13 (d, J = 7.0 Hz, 1H), 7.02 (D, J = 1.3Hz, 1H), 4.38 (dt, J = 12.7, 3.9Hz, 1H), 4.02 (td, J = 13.3,3.1Hz, 1H), 3.59 -3.34 (m, 3H), 3.21 (s, 2H), 3.04-2.87 (m, 3H), 2.78-2.63 (m, 2H). ESI-MS: 283 [M ++ l ].
Step 5. Synthesis of compound 7.
Compound 6 (850 mg, 3 mmol) was placed in a reaction flask, followed by the addition of 0.5 mL of acetic acid, 5 mL of 37% formaldehyde and sodium acetate (87 mg, 1.1 mmol) and warming to 100 ° C overnight. After the reaction was cooled to room temperature completely, 30 mL of methylene chloride was added to the reaction solution, 50% sodium hydroxide solution was added dropwise to adjust pH = 11-12, stirred for 0.5 hour, and the layers were separated and the organic phase was washed with 10 mL of saturated saline , Dried over anhydrous sodium sulfate, concentrated and separated on a silica gel column to give the compound 7 340 mg, yield 36%. ESI-MS: 313 [M ++ 1].
Step 6. Synthesis of Compound 8.
Compound 7 (340 mg, 1.1 mmol) was dissolved in 20 mL of dichloromethane and 4-dimethylaminopyridine (DMAP, 13 mg, 0.11 mmol) and Dess-Martin Periodinane 1.3 mmol) and reacted at room temperature for 3 hours. Join 20mL saturated sodium bicarbonate solution and 20mL dichloromethane, stirred for 5 minutes, filtered and the filtrate was separated. The organic phase was washed with saturated brine, dried over anhydrous sodium sulfate and concentrated. The compound 8 270mg was obtained by silica gel column, and the yield was 80%. 1 H NMR (300 MHz, CDCl 3 ) δ 9.64 (s, 1H), 7.76 (s, 1H), 7.34-7.26 (m, 3H), 7.16 (d, J = 6.7 Hz, 1H), 4.74 J = 14.5, 3.9 Hz, 1H), 4.31 (td, J = 14.1, 3.2 Hz, 1H), 3.53 (td, 3.03-2.89 (m, 4H), 2.64-2.81 (m, 4H); ESI-MS: 311 [M ++ l ].

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