Patents by Inventor Jyan Shankar Mahanty

Jyan Shankar Mahanty has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7759494
    Abstract: This invention relates to a process for preparation of taxanes comprising subjecting 7,10-diprotected intermediates 7-O-(2-haloacyl)baccatin III 6c or 7,10-O-di-(2-haloacyl)-10-deacetylbaccatin III 6b to a step of coupling with (4S,5R)-3-[(2-alkyl/aryl-2-trialkylsilyl)ethoxy-carbonyl]-4-aryl-2-substituted-1,3-oxazolidine-5-carboxylic acid 1 in the presence of a condensation agent, an activating agent and an aromatic hydrocarbon to obtain 7-O-[2-(haloacyl)]-13-[(4S,5R)-4-aryl-2-substituted-3(2-unsubstituted/substituted-2-trialkylsilyl)-ethoxycarbonyl-1,3-oxazolidinyl-5-carbonyl]baccatin III 7a or 7,10-di-O [2-(haloacyl)]-13-[(4S,5R)-4-aryl-2-substituted-3-(2-unsubstituted/substituted-2-trialkylsilyl)ethoxy-carbonyl-1,3-oxazolidinyl-5-carbonyl]-10-deacetylbaccatin III 7b; treating the coupled products 7-O-[2-(haloacyl)]-13-[(4S,5R)-4-aryl-2-substituted-3-(2-substituted-2-trialkylsilyl)ethoxy-carbonyl-1,3-oxazolidinyl-5-carbonyl]baccatin III 7a or 7,10-di-O-[2[(haloacyl)]-13-[(4S,5R)-4-aryl-2-substituted-3-(2-s
    Type: Grant
    Filed: June 15, 2007
    Date of Patent: July 20, 2010
    Assignee: Dabur India Limited
    Inventors: Arun Prakash Sharma, Subrata Sarkar, Jyan Shankar Mahanty
  • Patent number: 7750165
    Abstract: The invention provides two crystalline forms A and B of the skeletal muscle relaxant and anxiolytic agent, Metaxalone of formula (I), and a process for preparation thereof. The two crystalline forms A and B are bioavailable. The invention further provides pharmaceutical compositions comprising the two bioavailable crystalline forms, useful for the relief of discomforts associated with acute, painful musculoskeletal conditions.
    Type: Grant
    Filed: December 29, 2006
    Date of Patent: July 6, 2010
    Assignee: Fresenius Kabi Oncology Limited
    Inventors: Jayanta Chattopadhyay, Subrata Sarkar, Jyan Shankar Mahanty, Susanta Hazra, Moloy Mitra, Manoj Kumar Singh
  • Patent number: 7247738
    Abstract: This invention relates to a process for preparation of taxanes comprising subjecting 7,10-diprotected intermediates 7-O-(2-haloacyl)baccatin III 6c or 7,10-O-di-(2-haloacyl)-10-deacetylbaccatin III 6b to a step of coupling with (4S,5R)-3-[(2-alkyl/aryl-2-trialkylsilyl)ethoxy-carbonyl]-4-aryl-2-substituted-1,3-oxazolidine-5-carboxylic acid 1 in the presence of a condensation agent, an activating agent and an aromatic hydrocarbon to obtain 7-O-[2-(haloacyl)]-13-[(4S,5R)-4-aryl-2-substituted-3(2-unsubstituted/substituted-2-trialkylsilyl)-ethoxycarbonyl-1,3-oxazolidinyl-5-carbonyl]baccatin III 7a or 7,10-di-O[2-(haloacyl)]-13-[(4S,5R)-4-aryl-2-substituted-3-(2-unsubstituted/substituted-2-trialkylsilyl)ethoxy-carbonyl-1,3-oxazolidinyl-5-carbonyl]-10-deacetylbaccatin III 7b; treating the coupled products 7-O-[2-(haloacyl)]-13-[(4S,5R)-4-aryl-2-substituted-3-(2-substituted-2-trialkylsilyl)ethoxy-carbonyl-1,3-oxazolidinyl-5-carbonyl]baccatin III 7a or 7,10-di-O-[2[(haloacyl)]-13-[(4S,5R)-4-aryl-2-substituted-3-(2-su
    Type: Grant
    Filed: May 7, 2003
    Date of Patent: July 24, 2007
    Assignee: Dabur India Limited
    Inventors: Arun Prakash Sharma, Subrata Sarkar, Jyan Shankar Mahanty
  • Patent number: 6900342
    Abstract: A process for the preparation of taxanes comprising wherein R is a tert. butoxycarbonyl or benzoyl group; PMP is p-methoxyphenyl group; G1 is acetyl group; G2 is haloacetyl group comprising a) protecting the C-7 hydroxyl group of 10-deacetylbaccatin III with haloacetyl chlorides and then acetylating the C-10 hydroxyl group with acetyl chloride to obtain a protected 10-deacetylbaccatin III (1); b) subjecting the protected 10-deacetylbaccatin III (1) to coupling with an oxazolidine-5-caboxylic acid of formula 2 wherein R is tert. butoxycarbonyl or benzoyl; PMP is p-methoxyphenyl group in the presence of a condensation agent and an activating agent to obtain C-13 esters of formula 3; c) treating the coupled products 3 with weak acidic medium to open the oxazolidine ring to obtain intermediates of formula 4; wherein R is a tert.
    Type: Grant
    Filed: May 8, 2003
    Date of Patent: May 31, 2005
    Assignee: Dabur India Limited
    Inventors: Arun Prakash Sharma, Subrata Sarkar, Jyan Shankar Mahanty
  • Patent number: 6881852
    Abstract: A process for the purification of paclitaxel or docetaxel comprising: (a) mixing crude paclitaxel with a mixture of solvents such as alkane and chlorinated alkane, filtering the solid followed by drying to obtain paclitaxel or docetaxel of increased purity; (b) repeating step (a) one or more times to obtain paclitaxel or docetaxel of increased purity; (c) dissolving the solid obtained from step (b) in alkyl ketone followed by adding alkane thereto, filtering and drying the solid thus formed to obtain paclitaxel or docetaxel of increased purity; (d) repeating step (c) one or more times to increase the purity of paclitaxel or docetaxel; (e) dissolving the paclitaxel or docetaxel obtained from step (d) in alkanol and then adding water, filtering and drying the solid thus formed, to obtain paclitaxel of increased purity; (f) dissolving the solid obtained from step (e) in alkyl ketone, filtering, followed by adding alkane to the filtrate, filtering and drying the solid thus formed to obtain pure paclitaxel or pure
    Type: Grant
    Filed: February 5, 2003
    Date of Patent: April 19, 2005
    Assignee: Dabur India Limited
    Inventors: Arun Prakash Sharma, Jyan Shankar Mahanty, Subrata Sarkar
  • Publication number: 20030225291
    Abstract: A process for the purification of paclitaxel comprising: (a) mixing crude paclitaxel with a mixture of solvents such as alkane and chlorinated alkane, filtering the solid followed by drying to obtain paclitaxel of increased purity; (b) repeating step (a) one or more times to obtain paclitaxel of increased purity; (c) dissolving the solid obtained from step (b) in alkyl ketone followed by adding alkane thereto, filtering and drying the solid thus formed to obtain paclitaxel of increased purity; (d) repeating step (c) one or more times to increase the purity of paclitaxel; (e) dissolving the paclitaxel obtained from step (d) in alkanol and then adding water, filtering and drying the solid thus formed, to obtain paclitaxel of increased purity; and (f) dissolving the solid obtained from step (e) in alkyl ketone, filtering, followed by adding alkane to the filtrate, filtering and drying the solid thus formed to obtain pure paclitaxel.
    Type: Application
    Filed: February 5, 2003
    Publication date: December 4, 2003
    Inventors: Arun Prakash Sharma, Jyan Shankar Mahanty, Subrata Sarkar