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).

  • Thiourea derivatives of dihydropyridine NPY antagonists
    Patent number: 6391881
    Abstract: A series of antagonists of NPY have been synthesized and are comprised of thiourea linked piperazine and piperidine derivatives of 4-phenyl-1,4-dihydropyridines of Formula 1. where Z is NR7R8 or and X is CH or N. As antagonists of NPY-induced behavior, these compounds are expected to act as effective anorexiant agents in promoting weight loss and treating eating disorders.
    Type: Grant
    Filed: April 24, 2001
    Date of Patent: May 21, 2002
    Assignee: Bristol-Myers Squibb Company
    Inventor: Sing-Yuen Sit
  • Alkylamine derivatives of dihydropyridine NPY antagonists
    Publication number: 20020019384
    Abstract: A series of non-peptidergic antagonists of NPY have been synthesized and are comprises of amino and piperazine derivatives of 4-phenyl-1,4-dihydropyridines of Formula 1.
    Type: Application
    Filed: May 10, 2001
    Publication date: February 14, 2002
    Inventors: Graham S. Poindexter, Marc Bruce, Sing-Yuen Sit, Scott W. Martin
  • 4-Alkyl and 4-cycloalkyl derivatives of dihydropyridine NPY antagonists
    Publication number: 20010049370
    Abstract: A series of non-peptidergic antagonists of NPY have been synthesized and are comprised of 4-alkyl and cycloalkyl derivatives of dihydropyridines of Formula I.
    Type: Application
    Filed: April 24, 2001
    Publication date: December 6, 2001
    Inventor: Sing-Yuen Sit
  • Thiourea derivatives of dihydropyridine NPY antagonists
    Publication number: 20010047003
    Abstract: A series of antagonists of NPY have been synthesized and are comprised of thiourea linked piperazine and piperidine derivatives of 4-phenyl-1,4-dihydropyridines of Formula 1.
    Type: Application
    Filed: April 24, 2001
    Publication date: November 29, 2001
    Inventor: Sing-Yuen Sit
  • Squarate derivatives of dihydropyridine NPY antagonists
    Publication number: 20010047002
    Abstract: A series of antagonists of NPY have been synthesized and are comprised of squarate derivatives of 4-phenyl-1,4-dihydropyridines of Formula (I).
    Type: Application
    Filed: April 24, 2001
    Publication date: November 29, 2001
    Inventors: Sing-Yuen Sit, Graham S. Poindexter
  • Dihydropyrazine derivatives as NPY antagonists
    Patent number: 6177429
    Abstract: The present invention provides a series of non-peptidergic antagonists of NPY comprising piperidine and piperazine derivatives of 4-phenyl-1,4-dihydropyrazines of the Formula I wherein R, R1 X, Y and Z are defined herein. As antagonists of NPY-induced feeding behavior, these compounds are expected to act as effective anorexiant agents in promoting weight loss and treating eating disorders.
    Type: Grant
    Filed: June 6, 2000
    Date of Patent: January 23, 2001
    Assignee: Bristol-Myers Squibb Company
    Inventors: Sing-Yuen Sit, Yazhong Huang
  • Dihydropyridine NPY antagonists: cyanoguanidine derivatives
    Patent number: 6001836
    Abstract: A series of non-peptidergic antagonists of NPY have been synthesized and are comprised of cyanoguanidine derivatives of 4-phenyl-1,4-dihydropyridines of Formula (I). ##STR1## As antagonists of NPY-induced feeding behavior, these compounds are expected to act as effective anorexiant agents in promoting weight loss and treating eating disorders.
    Type: Grant
    Filed: May 26, 1998
    Date of Patent: December 14, 1999
    Assignee: Bristol-Myers Squibb Company
    Inventors: Graham S. Poindexter, R. Thomas Swann, Marc A. Bruce, Mendi A. Morton, Yazhong Huang, Sing-Yuen Sit, James Guy Breitenbucher
  • 4-aryl-3-hydroxyquinolin-2-one derivatives as ion channel modulators
    Patent number: 5922735
    Abstract: There is provided novel substituted 4-aryl-3-hydroxyquinolin-2-one derivatives of the formula ##STR1## wherein R is hydrogen or methyl;R.sup.1, R.sup.2, R.sup.3 and R.sup.4 each are independently hydrogen, bromo, chloro or trifluoromethyl, and when R.sup.1, R.sup.3 and R.sup.4 are hydrogen, R.sup.2 is nitro;R.sup.5 is hydrogen or methyl; andR.sup.6 is bromo or chloro;or a nontoxic pharmaceutically acceptable salt thereof, which are openers of the large-conductance calcium-activated potassium channels and are useful in the treatment of disorders which are responsive to the opening of the potassium channels.
    Type: Grant
    Filed: October 5, 1998
    Date of Patent: July 13, 1999
    Assignee: Bristol-Myers Squibb COmpany
    Inventors: Sing-Yuen Sit, Nicholas A. Meanwell
  • 4-aryl-3-hydroxyquinolin-2-one derivatives as ion channel modulators
    Patent number: 5892045
    Abstract: There is provided novel substituted 4-aryl-3-hydroxyquinolin-2-one derivatives of the formula ##STR1## wherein R is hydrogen or methyl;R.sup.1, R.sup.2, R.sup.3 and R.sup.4 each are independently hydrogen, bromo, chloro or trifluoromethyl, and when R.sup.1, R.sup.3 and R.sup.4 are hydrogen, R.sup.2 is nitro;R.sup.5 is hydrogen or methyl; andR.sup.6 is bromo or chloro;or a nontoxic pharmaceutically acceptable salt thereof, which are openers of the large-conductance calcium-activated potassium channels and are useful in the treatment of disorders which are responsive to the opening of the potassium channels.
    Type: Grant
    Filed: November 18, 1997
    Date of Patent: April 6, 1999
    Assignee: Bristol-Myers Squibb Company
    Inventors: Sing-Yuen Sit, Nicholas A. Meanwell
  • Hypocholesterolemic unsymmetrical dithiol ketals
    Patent number: 5321046
    Abstract: Disclosed herein are novel unsymmetrical dithiol ketals which are useful in the treatment or prevention of hypercholesterolemia, hyperlipoproteinemia, and atherosclerosis.
    Type: Grant
    Filed: October 27, 1992
    Date of Patent: June 14, 1994
    Assignee: Bristol-Myers Squibb Company
    Inventors: Sing-Yuen Sit, John J. Wright, Jeff A. Field
  • Antihypercholesterolemic tetrazole compounds
    Patent number: 5110940
    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.sub.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: May 6, 1991
    Date of Patent: May 5, 1992
    Assignee: Bristol-Myers Company
    Inventors: Sing-Yuen Sit, John J. Wright
  • Tetrazol-1-yl containing intermediates
    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
  • Tetrazole compounds
    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
  • Antihypercholesterolemic nitrile compounds
    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
  • Antihypercholesterolemic tetrazol-1-yl intermediates
    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
  • Antihypercholesterolemic nitrile compounds
    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
  • Intermediates and process for the preparation of antihypercholesterolemic tetrazole compounds
    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
  • Antihypercholesterolemic nitrile compounds
    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
  • Intermediates for the preparation of antihypercholesterolemic tetrazole compounds
    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
  • Antihypercholesterolemic tetrazole compounds
    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