Patents by Inventor Srinivasa Rao V. N Divvela

Srinivasa Rao V. N Divvela 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 the preparation of biphosphonic acids
    Patent number: 7528280
    Abstract: An improved process for bisphosphonylation of acids, substituted acids to obtain compounds with the formula using phosphorus trihalide, phosphorus acid, in presence of phenolic compounds as diluent/solvent.
    Type: Grant
    Filed: January 18, 2007
    Date of Patent: May 5, 2009
    Assignee: Aurobindo Pharma Ltd.
    Inventors: Subba Reddy Danda, Narayan K. A. S. S. Garimella, Srinivasa Rao V. N Divvela, Ramesh Dandala, Sivakumaran Meenakshisunderam
  • Process for the preparation of risedronate sodium hemi-pentahydrate
    Patent number: 7485726
    Abstract: The present invention relates to an improved process for the selective crystallization of 3-pyridyl-1-hydroxyethylidene-1,1-bisphosphonic acid sodium in pure hemi-pentahydrate form of Formula (I), by first converting 3-pyridyl-1-hydroxyethylidene-1,1-bisphosphonic acid into organic amine salt and then by replacing it with sodium salt.
    Type: Grant
    Filed: January 16, 2007
    Date of Patent: February 3, 2009
    Assignee: Aurobindo Pharma Ltd.
    Inventors: Srinivasa Rao V. N Divvela, Lenin Racha, Sivakumaran Meenakshisunderam, Ramesh Dandala
  • Process for the preparation of risedronate sodium hemi-pentahydrate
    Publication number: 20070173484
    Abstract: The present invention relates to an improved process for the selective crystallization of 3-pyridyl-1-hydroxyethylidene-1,1-bisphosphonic acid sodium in pure hemi-pentahydrate form of Formula (I), by first converting 3-pyridyl-1-hydroxyethylidene-1,1-bisphosphonic acid into organic amine salt and then by replacing it with sodium salt.
    Type: Application
    Filed: January 16, 2007
    Publication date: July 26, 2007
    Inventors: Srinivasa Rao V.N Divvela, Lenin Racha, Sivakumaran Meenakshisunderam, Ramesh Dandala
  • Process for the preparation of biphosphonic acids
    Publication number: 20070173645
    Abstract: An improved process for bisphosphonylation of acids, substituted acids to obtain compounds with the formula using phosphorus trihalide, phosphorus acid, in presence of phenolic compounds as diluent/solvent.
    Type: Application
    Filed: January 18, 2007
    Publication date: July 26, 2007
    Inventors: Subba Reddy Danda, Narayan K.A.S.S. Garimella, Srinivasa Rao V.N Divvela, Ramesh Dandala, Sivakumaran Meenakshisunderam