Patents by Inventor Durgadas Shyla Prasad

Durgadas Shyla Prasad 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).

  • Process for pure duloxetine hydrochloride
    Patent number: 8362279
    Abstract: A process for the preparation of pure Duloxetine hydrochloride comprises the steps of: a) reacting 1-(thiophen-2-yl)ethanone with dimethylamine hydrochloride, b) purifying the component in a solvent, c) reducing the component with an alkali metal borohydride, d) resolving the compound with a chiral acid, and treating the obtained compound with weak inorganic base, e) reacting the compound to give Duloxetine oxalate salt and f) converting the Duloxetine salt into its hydrochloride salt. Further the purifications of the obtained compound and of two intermediate products are described.
    Type: Grant
    Filed: January 4, 2007
    Date of Patent: January 29, 2013
    Assignee: MSN Laboratories Limited
    Inventors: Manne Satyanarayana Reddy, Muppa Kishore Kumar, Srinivasan Thirumalai Rajan, Durgadas Shyla Prasad
  • Process for pure montelukast sodium through pure intermediates as well as amine salts
    Patent number: 8115004
    Abstract: The present invention provides an improved process for the preparation of highly pure montelukast sodium through highly pure diol intermediate compound of formula (2) and (1)-(mercapto methyl)cyclopropane acetic acid methyl ester compound of formula (4) or mercaptomethyl cyclopropane acetic acid compound of formula (7). The present invention also provides novel organic amine salts of montelukast.
    Type: Grant
    Filed: November 19, 2007
    Date of Patent: February 14, 2012
    Assignee: MSN Laboratories Limited
    Inventors: Manne Satyanarayana Reddy, Muppa Kishore Kumar, Karamala Rama Subba Reddy, Durgadas Shyla Prasad
  • PROCESS FOR PURE MONTELUKAST SODIUM THROUGH PURE INTERMEDIATES AS WELL AS NOVEL AMINE SALTS
    Publication number: 20100056793
    Abstract: The present invention provides an improved process for the preparation of highly pure montelukast sodium through highly pure diol intermediate compound of formula (2) and (1)-(mercapto methyl)cyclopropane acetic acid methyl ester compound of formula (4) or mercaptomethyl cyclopropane acetic acid compound of formula (7). The present invention also provides novel organic amine salts of montelukast.
    Type: Application
    Filed: November 19, 2007
    Publication date: March 4, 2010
    Inventors: Manne Satyanarayana Reddy, Muppa Kishore Kumar, Karamala Rama Subba Reddy, Durgadas Shyla Prasad
  • Process for Pure Duloxetine Hydrochloride
    Publication number: 20090012315
    Abstract: A process for the preparation of pure Duloxetine hydrochloride comprises the steps of: a) reacting 1-(thiophen-2-yl)ethanone with dimethylamine hydrochloride, b) purifying the component in a solvent, c) reducing the component with an alkali metal borohydride, d) resolving the compound with a chiral acid, and treating the obtained compound with weak inorganic base, e) reacting the compound to give Duloxetine oxalate salt and f) converting the Duloxetine salt into its hydrochloride salt. Further the purifications of the obtained compound and of two intermediate products are described.
    Type: Application
    Filed: January 4, 2007
    Publication date: January 8, 2009
    Inventors: Manne Satyanarayana Reddy, Muppa Kishore Kumar, Srinivasan Thirumalai Rajan, Durgadas Shyla Prasad