Patents by Inventor Dharmendra Singh

Dharmendra Singh 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).

  • Publication number: 20240076274
    Abstract: A Janus G-C base as building block for a triazine based self-assembly of formula (I), a process for the preparation, and its application in developing supramolecular polymers, peptide nucleic acids (PNAs) and smart polymers thereof. A triazine based self-assembly of formula (I): wherein, ‘R’ is selected from the group comprising of linear or branched unsubstituted and substituted C1-C7 alkyl, unsubstituted and substituted aryl, unsubstituted and substituted natural amino acids which may be protected, linear or branched unsubstituted and substituted C1-C7 alcohols, or linear or branched unsubstituted and substituted C1-C7 amines.
    Type: Application
    Filed: January 25, 2022
    Publication date: March 7, 2024
    Inventors: Chhuttan Lal MEENA, Dharmendra SINGH, Gangadhar Jessy SANJAYAN
  • Patent number: 9492406
    Abstract: The present invention relates to a novel pharmaceutical composition having enhanced bioavailability through improved aqueous dissolution of poorly water soluble drugs, and to a method for preparing it. The invention more particularly relates to an oral pharmaceutical composition containing active ingredients of poor aqueous solubility, more specifically, antiparasitic and antipneumocystic drug Atovaquone alone or in combination with Proguanil.
    Type: Grant
    Filed: September 20, 2013
    Date of Patent: November 15, 2016
    Assignee: Ipca Laboratories Ltd.
    Inventors: Ashok Kumar, Dharmendra Singh, Pramilkumar Mathur, Thankachen Byju Nellithanath, Gaurav Sahal, Rakesh Kumar Bhasin, Durga Prasad Samantaray
  • Publication number: 20150238416
    Abstract: The present invention relates to a novel pharmaceutical composition having enhanced bioavailability through improved aqueous dissolution of poorly water soluble drugs, and to a method for preparing it. The invention more particularly relates to an oral pharmaceutical composition containing active ingredients of poor aqueous solubility, more specifically, antiparasitic and antipneumocystic drug Atovaquone alone or in combination with Proguanil.
    Type: Application
    Filed: September 20, 2013
    Publication date: August 27, 2015
    Inventors: Ashok Kumar, Dharmendra Singh, Pramilkumar Mathur, Thankachen Byju Nellithanath, Gaurav Sahal, Rakesh Kumar Bhasin, Durga Prasad Samantaray
  • Patent number: 8987234
    Abstract: Disclosed are complexes of an antipneumocystic compound and an antimalarial compound, processes for their preparation, pharmaceutical compositions and methods of using said complexes or compositions for the treatment and/or prophylaxis of parasitic infections.
    Type: Grant
    Filed: August 20, 2010
    Date of Patent: March 24, 2015
    Assignee: IPCA Laboratories Ltd.
    Inventors: Ashok Kumar, Dharmendra Singh, Pramilkumar Mathur, Vitthal Syryabhan Buchude
  • Publication number: 20120136062
    Abstract: Disclosed are complexes of an antipneumocystic compound and an antimalarial compound, processes for their preparation, pharmaceutical compositions and methods of using said complexes or compositions for the treatment and/or prophylaxis of parasitic infections.
    Type: Application
    Filed: August 20, 2010
    Publication date: May 31, 2012
    Applicant: IPCA Laboratories Ltd.
    Inventors: Ashok Kumar, Dharmendra Singh, Pramilkumar Mathur, Vitthal Syryabhan Buchude
  • Publication number: 20110166347
    Abstract: The present invention discloses an isolation and purification process for mycophenolic acid obtained from the fermentation process. Invention further discloses preparation of sodium salt of mycophenolic acid and mycophenolate mofetil from mycophenolic acid.
    Type: Application
    Filed: September 9, 2009
    Publication date: July 7, 2011
    Applicant: IPCA Laboratories Ltd.
    Inventors: Ashok Kumar, Dharmendra Singh, Umesh Luthara, Yogesh Mohandhai Patel
  • Patent number: 7847127
    Abstract: Disclosed herein is a novel process for preparation of atovaquone. The process includes reacting 1,4-naphthoquinone with trans-4-(4-chlorophenyl) cyclohexane carboxylic acid followed by halogenation to obtain a dihalo-compound. Further, dehydrohalogenation of the dihalo-compound produces a monohalogeno-compound which under goes hydrolysis to produce atovaquone. The invention also discloses atovaquone in a substantially pure and well defined polymorphic form designated as “Form IPCA-ATO,” and the preparation thereof.
    Type: Grant
    Filed: October 21, 2009
    Date of Patent: December 7, 2010
    Assignee: IPCA Laboratories Limited
    Inventors: Ashok Kumar, Suneel Yeshwant Dike, Pramil Kumar Mathur, Nellithanath Thankachen Byju, Brajesh Sharma, Swapnil Shreekant Kore, Vitthal Suryabhan Buchude, Dharmendra Singh
  • Patent number: 7847094
    Abstract: Disclosed herein is an industrial preparation of Quetiapine by the reaction of 11-piperazinyldibenzo[b,f][1,4]-thiazepine or its salt with 2-(2-chloroethoxy)ethanol in presence of an organic or inorganic base under neat or aqueous condition to form 11-[4-{2-(2-hydroxyethoxy)ethyl}-1-piperazinyl]dibenzo[b,f]-[1,4]thiazepine. The quetiapine free base obtained is further converted to its hemi-fumarate salt.
    Type: Grant
    Filed: June 8, 2007
    Date of Patent: December 7, 2010
    Assignee: IPCA Laboratories Limited
    Inventors: Ashok Kumar, Dharmendra Singh, Swapnali Hemant Patil, Ganesh Devidas Mahale, Uttamrao Arjunrao Sawant, Balasaheb Ganpat Jadhav, Ragneshkumar Rana
  • Publication number: 20100210848
    Abstract: The present invention discloses novel processes for preparing optically active sulphoxide compounds of formula I by asymmetric oxidation of prochiral sulphide compounds of Formula II. More particularly, the invention discloses processes for preparation of optically active proton pump Inhibitors (PPIs) or their optically active precursor (=intermediate) compounds (Formula I) that can be converted into pharmaceutically useful PPIs.
    Type: Application
    Filed: October 3, 2008
    Publication date: August 19, 2010
    Applicant: IPCA Laboratories Ltd.
    Inventors: Ashok Kumar, Dharmendra Singh, Nellithanath Thankachen Byju, Prasad Shankar Kadam, Harishankar Prahladkumar Vishwakarma, Vijay Ojha, Umeshkumar Suresh Ninawe
  • Patent number: 7763748
    Abstract: The present invention relates to a process for preparation of isotretinoin and more specifically, to a purification process for obtaining highly pure isotretinoin that is useful as a keratolytic agent, particularly useful for the treatment of acne. The process involves treating isotretinoin containing metal contamination and/or other impurities with a base in a suitable solvent to form a solution of isotretinoin, followed by adsorption, precipiation, and filtration or centrifugation.
    Type: Grant
    Filed: February 20, 2008
    Date of Patent: July 27, 2010
    Assignee: IPCA Laboratories Limited
    Inventors: Ashok Kumar, Dharmendra Singh, Ganesh Devidas Mahale, Ragnesh Kumar Rana, Mahesh Kharade
  • Publication number: 20100081847
    Abstract: Disclosed herein is a novel process for preparation of atovaquone. The process includes reacting 1,4-naphthoquinone with trans-4-(4-chlorophenyl) cyclohexane carboxylic acid followed by halogenation to obtain a dihalo-compound. Further, dehydrohalogenation of the dihalo-compound produces a monohalogeno-compound which under goes hydrolysis to produce atovaquone. The invention also discloses atovaquone in a substantially pure and well defined polymorphic form designated as “Form IPCA-ATO,” and the preparation thereof.
    Type: Application
    Filed: October 21, 2009
    Publication date: April 1, 2010
    Inventors: Ashok Kumar, Suneel Yeshwant Dike, Pramilkumar Mathur, Nellithanath Thankachen Byju, Brajesh Sharma, Swapnil Shreekant Kore, Vitthal Suryabhan Buchude, Dharmendra Singh
  • Publication number: 20090221715
    Abstract: The present invention relates to a novel polymorphic form of atovaquone. More particularly, it relates to a novel crystalline form, that has improved solubility and other bulk characteristics suitable for pharmaceutical application. The present invention also relates to processes for preparing a new polymorphic form of atovaquone and its use in industry.
    Type: Application
    Filed: February 27, 2009
    Publication date: September 3, 2009
    Inventors: Ashok Kumar, Suneel Yeshwant Dike, Pramilkumar Mathur, Nellithanath Thankachen Byju, Brajesh Sharma, Swapnil Shreekant Kore, Vitthal Suryabhan Buchude, Dharmendra Singh
  • Patent number: 7547791
    Abstract: A one-pot industrial process for preparing 1,2,3,9-tetrahydro-9-methyl-3-[(2-methyl-1H-imidazole-1-yl)methyl]-4H-carbazol-4-one of Formula-(I) from 1,2,3,9-tetrahydro-9-methyl-4H-carbazol-4-one of Formula-(IV) involves reaction of Formula (IV) with HNR1R2 salt and paraformaldehyde, where R1,R2 are independently alkyl groups or together forms a cyclic alkyl group, in a solvent system of acetic acid and hydrocarbon solvent to form a crude mixture of intermediate compounds of Formula (III) and (VIII), which is converted to ondansetron (Formula (I)) without isolation by reaction with 2methyimidazole in a suitable solvent system in the same pot.
    Type: Grant
    Filed: October 26, 2004
    Date of Patent: June 16, 2009
    Assignee: IPCA Laboratories Ltd.
    Inventors: Ashok Kumar, Dharmendra Singh, Atul Jadhav, Navinchandra Darpan Pandya, Shankar Deepak Panmand, Ramsingh Gajendrasingh Thakur
  • Patent number: 7459467
    Abstract: The present invention discloses selective and complete reduction of pyridine ring in a biaryl system comprising ?-substituted or non-substituted benzene ring and relates more specifically, not exclusively, for the manufacture of methylphenidate, which is used for treatment of Attention Deficit Hyperactive Disorder (ADHD) and also acts as central nervous system stimulant, by using palladium/C in a solvent such as C1-C4 alcohols in presence of molar quantities of organic and/or inorganic acids.
    Type: Grant
    Filed: June 10, 2005
    Date of Patent: December 2, 2008
    Assignee: IPCA Laboratories, Ltd.
    Inventors: Ashok Kumar, Dharmendra Singh, Swapnali Hemant Patil, Ganesh Devidas Mahale, Uttamrao Arjunrao Sawant
  • Publication number: 20080207946
    Abstract: The present invention relates to a process for preparation of isotretinoin and more specifically, to a purification process for obtaining highly pure isotretinoin that is useful as a keratolytic agent, particularly useful for the treatment of acne.
    Type: Application
    Filed: February 20, 2008
    Publication date: August 28, 2008
    Inventors: Ashok Kumar, Dharmendra Singh, Ganesh Devidas Mahale, Ragnesh Kumar Rana, Mahesh Kharade
  • Publication number: 20080009635
    Abstract: A one-pot industrial process for preparing 1,2,3,9-tetrahydro-9-methyl-3-[(2-methyl-1H-imidazole-1-yl)methyl]-4H-carbazol-4-one of Formula-(I) from 1,2,3,9-tetrahydro-9-methyl-4H-carbazol-4-one of Formula-(IV) involves reaction of Formula (IV) with HNR1R2 salt and paraformaldehyde, where R1,R2 are independently alkyl groups or together forms a cyclic alkyl group, in a solvent system of acetic acid and hydrocarbon solvent to form a crude mixture of intermediate compounds of Formula (III) and (VIII), which is converted to ondansetron (Formula (I)) without isolation by reaction with 2methyimidazole in a suitable solvent system in the same pot.
    Type: Application
    Filed: October 26, 2004
    Publication date: January 10, 2008
    Inventors: Ashok Kumar, Dharmendra Singh, Atul Jadhav, Navinchandra Pandya, Shankar Panmand, Ramsingh Thakur
  • Publication number: 20070293471
    Abstract: Disclosed herein is an industrial preparation of Quetiapine by the reaction of 11-piperazinyldibenzo[b,f][1,4]-thiazepine or its salt with 2-(2-chloroethoxy)ethanol in presence of an organic or inorganic base under neat or aqueous condition to form 11-[4-{2-(2-hydroxyethoxy)ethyl}-1-piperazinyl]dibenzo[b,f]-[1,4]thiazepine. The quetiapine free base obtained is further converted to its hemi-fumarate salt.
    Type: Application
    Filed: June 8, 2007
    Publication date: December 20, 2007
    Inventors: Ashok Kumar, Dharmendra Singh, Swapnali Patil, Ganesh Mahale, Uttamrao Sawant, Balasaheb Jadhav, Ragneshkumar Rana
  • Publication number: 20050277667
    Abstract: The present invention discloses selective and complete reduction of pyridine ring in a biaryl system comprising ?-substituted or nonsubstituted benzene ring and relates more specifically, not exclusively, for the manufacture of methylphenidate, which is used for treatment of Attention Deficit Hyperactive Disorder (ADHD) and also acts as central nervous system stimulant, by using palladium/C in a solvent such as C1-C4 alcohols in presence of molar quantities of organic and/or inorganic acids.
    Type: Application
    Filed: June 10, 2005
    Publication date: December 15, 2005
    Inventors: Ashok Kumar, Dharmendra Singh, Swapnali Patil, Ganesh Mahale, Uttamrao Sawant
  • Patent number: 6043364
    Abstract: N-7 isomer of the formula ##STR1## is converted into a N-9 isomer of the formula ##STR2## by heating a suspension of the N-7 isomer in an alkylating agent of the formula ##STR3##
    Type: Grant
    Filed: June 12, 1997
    Date of Patent: March 28, 2000
    Assignee: Lupin Laboratories Limited
    Inventors: Ashoke Kumar, Dharmendra Singh, Mukesh Jagannath Wani, Narendra Sriram Joshi, Pravin Sahadev Thombre, Ajay Singh Rawat
  • Patent number: 5821367
    Abstract: This invention relates to an improved regiospecific process for the synthesis of acyclic nucleosides such as, acyclovir and ganciclovir, anti-viral compounds especially effective against herpes virus, and intermediates thereof starting from dyacylguanine and an alkylating agent, selected from 2-oxa-1,4-butanediol diacetate (OBDDA), 1,4-diacetoxy-3-acetoxymethyl-2-oxa-butane, 1,4-dibenzyloxy-3-acetoxymethyl-2-oxabutane. The reaction is carried out in the absence of an acid catalyst and a solvent.
    Type: Grant
    Filed: April 5, 1996
    Date of Patent: October 13, 1998
    Assignee: Lupin Laboratories Limited
    Inventors: Ashoke Kumar, Dharmendra Singh, Mukesh Jagannath Wani, Narendra Sriram Joshi, Pravin Sahadev Thombre, Ajay Singh Rawat