Patents by Inventor John S Ng

John S Ng 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).

  • Method of preparing retroviral protease inhibitor intermediates
    Patent number: 7060851
    Abstract: Chiral hydroxyethylamine, hydroxyethylurea or hydroxyethylsulfonamide isostere containing retroviral protease and renin inhibitors can be prepared by multi-step syntheses that utilize key chiral amine intermediates. This invention is a cost effective method of obtaining such key chiral amine intermediates enantiomerically, diastereomerically and chemically pure. The method is suitable for large scale (multikilogram) productions. This invention also encompasses organic acid and inorganic acid salts of the amine intermediates.
    Type: Grant
    Filed: October 12, 2004
    Date of Patent: June 13, 2006
    Assignee: G.D. Searle & Co.
    Inventors: John S Ng, Claire A Przybyla, Shu-Hong Zhang
  • Method for preparing intermediates useful in synthesis of retroviral protease inhibitors
    Patent number: 6974876
    Abstract: A synthesis is described for intermediates which are readily amenable to the large scale preparation of hydroxyethylurea-based chiral HIV protease inhibitors. The method includes forming a diastereoselective epoxide from a chiral alpha amino aldehyde.
    Type: Grant
    Filed: February 10, 2003
    Date of Patent: December 13, 2005
    Assignee: G.D. Searle & Co.
    Inventors: John S Ng, Claire A. Przybyla, Richard A Mueller, Michael L Vazquez, Daniel P Getman
  • Method of preparing retroviral protease inhibitor intermediates
    Patent number: 6849760
    Abstract: Chiral hydroxyethylamine, hydroxyethylurea or hydroxyethylsulfonamide isostere containing retroviral protease and renin inhibitors can be prepared by multi-step syntheses that utilize key chiral amine intermediates. This invention is a cost effective method of obtaining such key chiral amine intermediates enantiomerically, diastereomerically and chemically pure. The method is suitable for large scale (multikilogram) productions. This invention also encompasses organic acid and inorganic acid salts of the amine intermediates.
    Type: Grant
    Filed: December 23, 2002
    Date of Patent: February 1, 2005
    Assignee: G. D. Searle & Co.
    Inventors: John S Ng, Claire S Przybyla, Shu-Hong Zhang
  • Method of preparing intermediates useful in synthesis of retroviral protease inhibitors
    Patent number: 6570027
    Abstract: A synthesis is described for intermediates which are readily amenable to the large scale preparation of hydroxyethylurea-based chiral HIV protease inhibitors. The method includes forming a diastereoselective epoxide from a chiral alpha amino aldehyde.
    Type: Grant
    Filed: April 3, 2002
    Date of Patent: May 27, 2003
    Assignee: G. D. Searle & Co.
    Inventors: John S Ng, Claire A. Przybyla, Richard A Mueller, Michael L Vazquez, Daniel P Getman
  • Method of preparing retroviral protease inhibitor intermediates
    Patent number: 6515162
    Abstract: Chiral hydroxyethylamine, hydroxyethylurea or hydroxyethylsulfonamide isostere containing retroviral protease and renin inhibitors can be prepared by multi-step syntheses that utilize key chiral amine intermediates. This invention is a cost effective method of obtaining such key chiral amine intermediates enantiomerically, diastereomerically and chemically pure. The method is suitable for large scale (multikilogram) productions. This invention also encompasses organic acid and inorganic acid salts of the amine intermediates.
    Type: Grant
    Filed: December 21, 2000
    Date of Patent: February 4, 2003
    Assignee: G.D. Searle & Co.
    Inventors: John S Ng, Claire S. Przybyla, Shu-Hong Zhang
  • Method for making intermediates useful in synthesis of retroviral protease inhibitors
    Patent number: 6388094
    Abstract: A synthesis is described for intermediates which are readily amenable to the large scale preparation of hydroxyethylurea-based chiral HIV protease inhibitors. The method includes forming a diastereoselective epoxide from a chiral alpha amino aldehyde.
    Type: Grant
    Filed: November 1, 1999
    Date of Patent: May 14, 2002
    Assignee: G.D. Searle & Co.
    Inventors: John S Ng, Claire A. Przybyla, Richard A Mueller, Michael L Vazquez, Daniel P Getman
  • Method of preparing retroviral protease inhibitor intermediates
    Patent number: 6201150
    Abstract: Chiral hydroxyethylamine, hydroxyethylurea or hydroxyethylsulfonamide isostere containing retroviral protease and renin inhibitors can be prepared by multi-step syntheses that utilize key chiral amine intermediates. This invention is a cost effective method of obtaining such key chiral amine intermediates enantiomerically, diastereomerically and chemically pure. The method is suitable for large scale (multikilogram) productions. This invention also encompasses organic acid and inorganic acid salts of the amine intermediates.
    Type: Grant
    Filed: February 17, 1998
    Date of Patent: March 13, 2001
    Assignee: G.D. Searle & Co.
    Inventors: John S Ng, Claire S Przybyla, Shu-Hong Zhang
  • Method of preparing intermediates for retroviral protease inhibitors
    Patent number: 5872298
    Abstract: A synthesis is described for intermediates which are readily amenable to the large scale preparation of hydroxyethylurea-based chiral HIV protease inhibitors. The method includes forming a diastereoselective epoxide or cyanohydrin from a chiral alpha amino aldehyde.
    Type: Grant
    Filed: April 9, 1997
    Date of Patent: February 16, 1999
    Assignee: G. D. Searle & Co.
    Inventors: John S Ng, Claire A Przybyla, Richard A Mueller, Michael L Vazquez, Daniel P Getman, John J Freskos, Gary A DeCrescenzo, Deborah E Bertenshaw, Robert M Heintz, Suhong Zhang, Chin Liu, Scott A Laneman
  • Method of preparing intermediates for retroviral protease inhibitors
    Patent number: 5872299
    Abstract: A synthesis is described for intermediates which are readily amenable to the large scale preparation of hydroxyethylurea-based chiral HIV protease inhibitors. The method includes forming a diastereoselective epoxide or cyanohydrin from a chiral alpha amino aldehyde.
    Type: Grant
    Filed: May 8, 1997
    Date of Patent: February 16, 1999
    Assignee: G. D. Searle & Co.
    Inventors: John S Ng, Claire A Przybyla, Richard A Mueller, Michael L Vazquez, Daniel P Getman, John J Freskos, Gary A DeCrescenzo, Deborah E Bertenshaw, Robert M Heintz, Suhong Zhang, Chin Liu, Scott A Laneman