Patents by Inventor Om Dutt Tyagi

Om Dutt Tyagi 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: 8513455
    Abstract: The present invention relates to a crystalline oxybutynin base and process for preparing the same. Further, this invention discloses a process for preparing an acid addition salt of oxybutynin employing the crystalline oxybutynin base.
    Type: Grant
    Filed: February 4, 2009
    Date of Patent: August 20, 2013
    Assignee: Matrix Laboratories Limited
    Inventors: Purna Chandra Ray, Madhuresh Sethi, Sanjay Mahajan, Om Dutt Tyagi
  • Patent number: 8350030
    Abstract: Disclosed herein an improved process for producing 5-Fluoro-1-(2R,5S)-[2-(hydroxymethyl)-1,3-oxathiolan-5-yl]cytosine and its pharmaceutical acceptable salts.
    Type: Grant
    Filed: December 5, 2008
    Date of Patent: January 8, 2013
    Assignee: Matrix Laboratories Limited
    Inventors: Om Dutt Tyagi, Umamaheswar Vasireddy Rao, Vellanki Sivarama Prasad, Arabinda Sahu
  • Patent number: 8329952
    Abstract: The present invention relates to process for the preparation of novel crystalline Desmethylvenlafaxine succinate polymorphic Forms-A, B. The present invention also relates to novel processes for the preparation of 0-Desmethylvenlafaxine succinate polymorphic Forms-(I), (II), (III) and amorphous.
    Type: Grant
    Filed: July 15, 2008
    Date of Patent: December 11, 2012
    Assignee: Matrix Laboratories Limited
    Inventors: Ramakoteswara Rao Jetti, Purandhar Koilkonda, Jagan Mohana Chary Tummanapally, Mohana Vamsi Krishna Vadlamudi, Prasanth Kumar Barik, Om Dutt Tyagi
  • Patent number: 8318930
    Abstract: Disclosed herein is a novel process for preparing polymorphic Forms of (S)-6-chloro-(cyclopropylethynyl)-1,4-di-hydro-4-(trifluoromethyl)-2H-3,1-benzoxazin-2-one referred as M1, I, II, ?, and ?.
    Type: Grant
    Filed: December 24, 2008
    Date of Patent: November 27, 2012
    Assignee: Matrix Laboratories Limited
    Inventors: Om Dutt Tyagi, Ramakoteswara Rao Jetti, B. A. Ramireddy
  • Patent number: 8309723
    Abstract: Present invention relates to an improved process for the preparation of Zopiclone and its enantiomerically enriched isomer (Eszopiclone). 6-(5-Chloropyridin-2-yl)-5-hydroxy-7-oxo-5,6-dihydropyrrolo[3,4-b]pyrazine is reacted with 1-chloro-carbonyl-4-methylpiperazine in the presence of alkali earth metal carbonates, hydroxides or oxides in a solvent medium to give Zopiclone. It is reacted with optically active acid in a mixture of water and water miscible organic solvent followed by work up to give Eszopiclone. The present invention also relates to process for the conversion of (R) or (S) Zopiclone to 6-(5-chloropyrid-2-yl)-5-hydroxy-7-oxo-5,6-dihydro-pyrrolo-[3,4-b]-pyrazine of the intermediate which can be converted to racemic Zopiclone.
    Type: Grant
    Filed: April 10, 2008
    Date of Patent: November 13, 2012
    Assignee: Mylan Laboratories Ltd.
    Inventors: Om Dutt Tyagi, Tushar Kumar Srivastava, Vellanki Siva Ram Prasad, Dnyandev Ragho Rane, Bandi Naga Durga Rao, Daggula Srinivas Reddy
  • Patent number: 8304578
    Abstract: The present invention relates to an improved, process for large scale production of 1-[2-(dimethylamino)-1-(4-phenol)ethyl]cyclohexanol (O-desmethylvenlafaxine) or its pharmaceutically acceptable salts with increased yield and minimal impurities.
    Type: Grant
    Filed: December 26, 2008
    Date of Patent: November 6, 2012
    Assignee: Matrix Laboratories Limited
    Inventors: Om Dutt Tyagi, Saswata Lahiri, Purandhar Koilkonda, Jagan Mohana Chary Tummanapally, Mohan Vamsi Krishna Vadlamudi, Venkata Bala Kishore Sarma Inupakutika, Surya Nageswara Rao Achanta
  • Patent number: 8258312
    Abstract: An improved process for the preparation of substantially pure valsartan employing suitable reagents such as chelating agent and reaction conditions.
    Type: Grant
    Filed: June 26, 2008
    Date of Patent: September 4, 2012
    Assignee: Mylan Laboratories Ltd
    Inventors: Om Dutt Tyagi, Jakka Devendra Rao, Katukuri Aravind Kumar, Dammalapati Ventaka Lakshmi Narasimha Rao
  • Patent number: 8247568
    Abstract: The present invention relates to a process for the preparation of pure Rabeprazole sulfoxide using the solvent mixture for the extraction steps and this invention further relates to the process for the preparation of amorphous Rabeprazole sodium using pure rabeprazole base in presence of aqueous NaOH and water miscible solvent and adding an anti-solvent.
    Type: Grant
    Filed: June 19, 2008
    Date of Patent: August 21, 2012
    Assignee: Matrix Laboratories Ltd
    Inventors: Om Dutt Tyagi, Purna Chandra Ray, Madhuresh Kumar Sethi, Bhausaheb Chavhan
  • Patent number: 8008478
    Abstract: The present invention provides an improved process for the preparation of Cefixime of formula (I), a cephalosporine antibiotic with an improved quality in regard to color and solubility. This process includes: (i) reaction of 7-?-(4-chloro-2-alkoxycarbonyl methoxyimino-3-oxobutyromido)-3-cephem-4-carboxylic acid (V) with thiourea at pH 5.0 to 6.0 at temperature 25-40° C. in water, (ii) carbon treatment to the reaction mixture in presence of sodium dithionite or ethylenediaminetetraacetic acid (EDTA) followed by filtration, (iii) acidification of the filtrate obtained in step (ii) to pH 2.0 to 3.0 with acid at 50-80° C. to give cefixime ester (IV) (iv) alkaline hydrolysis of cefixime ester of formula (IV) in water followed by acidification to pH 5.0 to 6.0, (v) precipitation of cefixime (I) by adding ketone solvent followed by acidification to pH 2.0 to 3 and (vi) isolation of solid.
    Type: Grant
    Filed: December 19, 2005
    Date of Patent: August 30, 2011
    Assignee: Lupin Limited
    Inventors: Om Dutt Tyagi, Dnyandeo Ragho Rane, Sanjay Mahajan, Yuvraj Atmaram Chavan
  • Publication number: 20110087042
    Abstract: The present invention relates to a crystalline oxybutynin base and process for preparing the same. Further, this invention discloses a process for preparing an acid addition salt of oxybutynin employing the crystalline oxybutynin base.
    Type: Application
    Filed: February 4, 2009
    Publication date: April 14, 2011
    Applicant: MATRIX LABORATORIES LIMITED
    Inventors: Chandra Purna Ray, Madhuresh Sethi, Sanjay Mahajan, Om Dutt Tyagi
  • Publication number: 20100286447
    Abstract: The present invention relates to an improved, process for large scale production of 1-[2-(dimethylamino)-1-(4-phenol)ethyl]cyclohexanol (O-desmethylvenlafaxine) or its pharmaceutically acceptable salts with increased yield and minimal impurities.
    Type: Application
    Filed: December 26, 2008
    Publication date: November 11, 2010
    Applicant: MATRIX LABORATORIES LIMITED
    Inventors: Om Dutt Tyagi, Saswata Lahiri, Purandhar Koilkonda, Jagan Mohana Chary Tummanapally, Mohan Vamsi Krishna Vadlamudi, Venkata Bala Kishore Sarma Inupakutika, Surya Nageswara Rao Achanta
  • Publication number: 20100274007
    Abstract: Disclosed herein is a novel process for preparing polymorphic Forms of (S)-6-chloro-(cyclopropylethynyl)-1,4-di-hydro-4-(trifluoromethyl)-2H-3,1-benzoxazin-2-one referred as M1, I, II, ?, and ?.
    Type: Application
    Filed: December 24, 2008
    Publication date: October 28, 2010
    Applicant: MATRIX LABORATORIES LIMITED
    Inventors: Om Dutt Tyagi, Ram K. R. Jetti, B. A. Ramireddy
  • Publication number: 20100256372
    Abstract: Disclosed herein an improved process for producing 5-Fluoro-1-(2R,5S)-[2-(hydroxymethyl)-1,3-oxathiolan-5-yl]cytosine and its pharmaceutical acceptable salts.
    Type: Application
    Filed: December 5, 2008
    Publication date: October 7, 2010
    Applicant: MATRIX LABORATORIES LIMITED
    Inventors: Om Dutt Tyagi, Umamaheswar Vasireddy Rao, Vellanki Sivarama Prasad, Arabinda Sahu
  • Publication number: 20100197932
    Abstract: An improved process for the preparation of substantially pure valsartan employing suitable reagents such as chelating agent and reaction conditions.
    Type: Application
    Filed: June 26, 2008
    Publication date: August 5, 2010
    Applicant: MATRIX LABORATORIES LTD
    Inventors: Om Dutt Tyagi, Jakka Devendra Rao, Katukuri Aravind Kumar, Dammalapati Ventaka Lakshmi Narasimha Rao
  • Publication number: 20100191015
    Abstract: The present invention relates to process for the preparation of novel crystalline Desmethylvenlafaxine succinate polymorphic Forms-A, B. The present invention also relates to novel processes for the preparation of 0-Desmethylvenlafaxine succinate polymorphic Forms-(I), (II), (III) and amorphous.
    Type: Application
    Filed: July 15, 2008
    Publication date: July 29, 2010
    Applicant: MATRIX LABORATORIES LIMITED
    Inventors: Ramakoteswara Rao Jetti, Purandhar Koilkonda, Jagan Mohana Chary Tummanapally, Mohana Vamsi, Krishna Vadlamudi, Prasanth Kumar Barik, Om Dutt Tyagi
  • Publication number: 20100190989
    Abstract: The present invention relates to a process for the preparation of pure Rabeprazole sulfoxide using the solvent mixture for the extraction steps and this invention further relates to the process for the preparation of amorphous Rabeprazole sodium using pure rabeprazole base in presence of aqueous NaOH and water miscible solvent and adding an anti-solvent.
    Type: Application
    Filed: June 19, 2008
    Publication date: July 29, 2010
    Applicant: MATRIX LABORATORIES LTD
    Inventors: Om Dutt Tyagi, Purna Chandra Ray, Madhuresh Kumar Sethi, Bhausaheb Chavhan
  • Patent number: 7728136
    Abstract: A novel method for preparing a compound of formula I which comprises of coupling the piperazine derivative of formula II with alkyl halide containing compound of the formula III by heating in solvent free conditions or, optionally, in a minimum quantity of non-aqueous suspending liquid, in presence of a catalyst and a neutralizing agent to neutralize the hydrohalic acid.
    Type: Grant
    Filed: June 16, 2005
    Date of Patent: June 1, 2010
    Assignee: Lupin Limited
    Inventors: Om Dutt Tyagi, Tushar Kumar Srivastava, Yogendra Kumar Chauhan, Vasanth Kumar Nalam
  • Publication number: 20100056785
    Abstract: Present invention relates to an improved process for the preparation of Zopiclone and its enantiomerically enriched isomer (Eszopiclone). 6-(5-Chloropyridin-2-yl)-5-hydroxy-7-oxo-5,6-dihydropyrrolo[3,4-b]pyrazine is reacted with 1-chloro-carbonyl-4-methylpiperazine in the presence of alkali earth metal carbonates, hydroxides or oxides in a solvent medium to give Zopiclone. It is reacted with optically active acid in a mixture of water and water miscible organic solvent followed by work up to give Eszopiclone. The present invention also relates to process for the conversion of (R) or (S) Zopiclone to 6-(5-chloropyrid-2-yl)-5-hydroxy-7-oxo-5,6-dihydro-pyrrolo-[3,4-b]-pyrazine of the intermediate which can be converted to racemic Zopiclone.
    Type: Application
    Filed: April 10, 2008
    Publication date: March 4, 2010
    Inventors: Om Dutt Tyagi, Tushar Kumar Srivastava, Vellanki Siva Ram Prasad, Dnyandev Ragho Rane, Bandi Naga Durga Rao, Daggula Srinivas Reddy
  • Publication number: 20090227787
    Abstract: The present invention provides an improved process for the preparation of Cefixime of formula (I), a cephalosporine antibiotic with an improved quality in regard to color and solubility.
    Type: Application
    Filed: December 19, 2005
    Publication date: September 10, 2009
    Applicant: LUPIN LIMITED
    Inventors: Om Dutt Tyagi, Dnyandeo Ragho Rane, Sanjay Mahajan, Yuvraj Atmaram Chavan
  • Publication number: 20090118509
    Abstract: A process for the preparation of compounds of Formula I and their pharmaceutically acceptable acid addition salt wherein, R1 is phenyl or substituted phenyl R2 is selected from a group consisting of phenyl which is unsubstituted or substituted with 1 or 2 substituents, each independently selected from Cl, F, or pyridine, or naphthalene, or NHCOR4 wherein R4 is aryl, unsubstituted or substituted heteroaryl, unsubstituted or substituted heterocyclyl. R3 is selected from a group of formula wherein R5 is phenyl which is unsubstituted or substituted with 1 or 2 substituents each independently selected from the group consisting of halogen, C1-C4 alkyl, C1-C4 alkoxy, nitro, amino, haloalkyl, haloalkoxy etc.
    Type: Application
    Filed: April 5, 2006
    Publication date: May 7, 2009
    Applicant: Lupin limited
    Inventors: Sudershan Kumar Arora, Neelima Sinha, Sanjay Jain, Ram Shankar Upadhayaya, Om Dutt Tyagi, Vasanth Nalam, Yogendra Kumar Chauhan