Patents by Inventor Sing-Yuen Sit

Sing-Yuen Sit 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: 5070206
    Abstract: Compounds of the formula ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 each are independently hydrogen, halogen, C.sub.1-4 alkyl, C.sub.1-4 alkoxy or trifluoromethyl;R is hydrogen, C.sub.1-4 alkyl or phenyl;A is ##STR2## R.sup.5 is hydrogen, a hydrolyzable ester group or a cation to form a non-toxic pharmaceutically acceptable salt,are novel antihypercholesterolemic agents which inhibit cholesterol biosynthesis. Intermediates and processes for their preparation are disclosed.
    Type: Grant
    Filed: February 13, 1991
    Date of Patent: December 3, 1991
    Assignee: Bristol-Myers Company
    Inventors: Sing-Yuen Sit, John J. Wright
  • Patent number: 5068346
    Abstract: Compounds of the formula ##STR1## wherein R.sup.1 and R.sup.4 each are independently hydrogen, halogen, C.sub.1-4 alkyl, C.sub.1-4 alkoxy, or trifluoromethyl;R.sup.2, R.sup.3,R.sup.5 and R.sup.6 each are independently hydrogen, halogen C.sub.1-4 alkyl or C.sub.1-4 alkoxy;tet is ##STR2## n is an integer of from 0 to 2, inclusive; A is ##STR3## R.sup.7 is hydrogen, C.sub.1-4 alkyl, C.sub.1-4 alkoxy(lower) alkyl or (2-methoxyethoxy)methyl;X is --OH or .dbd.O; andR.sup.8 is hydrogen, a hydrolyzable ester group or a cation to form a non-toxic pharmaceutically acceptable salt,are novel antihypercholesterolemic agents which inhibit cholesterol biosynthesis. Intermediates and processes for their preparation are disclosed.
    Type: Grant
    Filed: November 17, 1989
    Date of Patent: November 26, 1991
    Assignee: Bristol-Myers Company
    Inventors: Sing-Yuen Sit, John J. Wright
  • Patent number: 5028730
    Abstract: Compounds of the formula ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 each are independently hydrogen, halogen, C.sub.1-4 alkyl, C.sub.1-4 alkoxy or trifluoromethyl;A is ##STR2## and R.sup.5 is hydrogen, a hydrolyzable ester group or a cation to form a non-toxic pharmaceutically acceptable salt,are novel antihypercholesterolemic agents which inhibit cholesterol biosynthesis. Intermediates and processes for their preparation are disclosed.
    Type: Grant
    Filed: February 23, 1990
    Date of Patent: July 2, 1991
    Assignee: Bristol-Myers Company
    Inventors: Sing-Yuen Sit, John J. Wright
  • Patent number: 5010205
    Abstract: Compounds of the formula ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 each are independently hydrogen, halogen, C.sub.1-4 alkyl, C.sub.1-4 alkoxy or trifluoromethyl;R is hydrogen, C.sub.1-4 alkyl or phenyl;A is ##STR2## R.sup.5 is hydrogen, a hydrolyzable ester group or a cation to form a non-toxic pharmaceutically acceptable salt,are novel antihypercholesterolemic agents which inhibit cholesterol biosynthesis. Intermediates and processes for their preparation are disclosed.
    Type: Grant
    Filed: July 28, 1989
    Date of Patent: April 23, 1991
    Assignee: Bristol-Myers Company
    Inventors: Sing-Yuen Sit, John J. Wright
  • Patent number: 4981991
    Abstract: Compounds of the formula ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 each are independently hydrogen, halogen, C.sub.1-4 alkyl, C.sub.1-4 alkoxy or trifluoromethyl;A is ##STR2## R.sup.5 is hydrogen, a hydrolyzable ester group or a cation to a form a non-toxic pharmaceutically acceptable salt,are novel antihypercholesterolemic agents which inhibit cholesterol biosynthesis. Intermediates and processes for their preparation are disclosed.
    Type: Grant
    Filed: February 23, 1990
    Date of Patent: January 1, 1991
    Assignee: Bristol-Myers Company
    Inventors: Sing-Yuen Sit, John J. Wright
  • Patent number: 4939265
    Abstract: This invention provides novel tetrazole intermediates of the formula ##STR1## wherein R.sup.1 and R.sup.4 each are independently hydrogen, halogen, C.sub.1-4 alkyl, C.sub.1-4 alkoxy or trifluoromethyl;R.sup.2, R.sup.3, R.sup.5 and R.sup.6 each are independently hydrogen, halogen, C.sub.1-4 alkyl or C.sub.1-4 alkoxy;B is hydrogen, C.sub.1-4 alkoxycarbonyl, CH.sub.2 Y or CH.sub.2 Z;Y is hydrogen, hydroxyl or X;Z is ##STR2## X is bromo, chloro or iodo; R.sup.10 is C.sub.1-4 alkyl; andR.sup.11 is phenyl which is unsubstituted or substituted by one or two C.sub.1-4 alkyl or chloro substituents.and processes thereof which are useful for the preparation of antihypercholesterolemic agents.
    Type: Grant
    Filed: November 1, 1989
    Date of Patent: July 3, 1990
    Assignee: Bristol-Myers Company
    Inventors: John J. Wright, Sing-Yuen Sit, Neelakantan Balasubramanian, Peter J. Brown
  • Patent number: 4927944
    Abstract: Compounds of the formula ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 each are independently hydrogen, halogen, C.sub.1-4 alkyl, C.sub.1-4 alkoxy or trifluoromethyl;A is ##STR2## and R.sup.5 is hydrogen, a hydrolyzable ester group or a cation to form a non-toxic pharmaceutically acceptable salt,are novel antihypercholesterolemic agents which inhibit cholesterol biosynthesis. Intermediates and processes for their preparation are disclosed.
    Type: Grant
    Filed: August 25, 1988
    Date of Patent: May 22, 1990
    Assignee: Bristol-Myers Company
    Inventors: Sing-Yuen Sit, John J. Wright
  • Patent number: 4898949
    Abstract: This invention provides novel tetrazole intermediates of the formula ##STR1## wherein R.sup.1 and R.sup.4 each are independently hydrogen, halogen, C.sub.1-4 alkyl, C.sub.1-4 alkoxy or trifluoromethyl;R.sup.2,R.sup.3,R.sup.5 and R.sup.6 each are independently hydrogen, halogen, C.sub.1-4 alkyl or C.sub.1-4 alkoxy;B is hydrogen, C.sub.1-4 alkoxycarbonyl, CH.sub.2 Y or CH.sub.2 Z;Y is hydrogen, hydroxyl or X;Z is ##STR2## X is bromo, chloro or iodo; R.sup.10 is C.sub.1-4 alkyl; andR.sup.11 is phenyl which is unsubstituted or substituted by one or two C.sub.1-4 alkyl or chloro substituents.and processes thereof which are useful for the preparation of antihypercholesterolemic agents.
    Type: Grant
    Filed: February 18, 1988
    Date of Patent: February 6, 1990
    Assignee: Bristol-Myers Company
    Inventors: John J. Wright, Sing-Yuen Sit, Neelakantan Balasubramanian, Peter J. Brown
  • Patent number: 4897490
    Abstract: Compounds of the formula ##STR1## wherein R.sup.1 and R.sup.4 each are independently hydrogen, halogen, C.sub.1-4 alkyl, C.sub.1-4 alkoxy, or trifluoromethyl;R.sup.2, R.sup.3, R.sup.5 and R.sup.6 each are independently hydrogen, halogen C.sub.1-4 alkyl or C.sub.1-4 alkoxy;tet is ##STR2## n is an integer of from 0 to 2, inclusive; A is ##STR3## R.sup.7 is hydrogen, C.sub.1-4 alkyl, C.sub.1-4 alkoxy(lower) alkyl or (2-methoxyethoxy)methyl;X is --OH or .dbd.O; andR.sup.8 is hydrogen, a hydrolyzable ester group or a cation to form a non-toxic pharmaceutically acceptable salt,are novel antihypercholesterolemic agents which inhibit cholesterol biosynthesis. Intermediates and processes for their preparation are disclosed.
    Type: Grant
    Filed: February 18, 1988
    Date of Patent: January 30, 1990
    Assignee: Bristol-Meyers Company
    Inventors: Sing-Yuen Sit, John J. Wright
  • Patent number: 4870187
    Abstract: Compounds of the formula ##STR1## wherein R.sup.1, R.sup.2, R.sup.3, and R.sup.4 each are independently hydrogen, halogen, C.sub.1-4 alkyl, C.sub.1-4 alkoxy or trifluoromethyl;R is hydrogen, C.sub.1-4 alkyl or phenyl;A is ##STR2## R.sup.5 is hydrogen, a hydrolyzable ester group or a cation to form a non-toxic pharmaceutically acceptable salt,are novel antihypercholesterolemic agents which inhibit cholesterol biosynethesis. Intermediates and processes for their preparation are disclosed.
    Type: Grant
    Filed: August 23, 1988
    Date of Patent: September 26, 1989
    Assignee: Bristol-Myers Company
    Inventors: Sing-Yuen Sit, John J. Wright