Patents by Inventor John Y. L. Chung

John Y. L. Chung 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 synthesis of gonadotropin releasing hormone antagonists
    Publication number: 20030013876
    Abstract: The present invention relates to a process for preparing a compound of gonadotropin releasing hormone antagonists having a Formula I, 1
    Type: Application
    Filed: April 5, 2002
    Publication date: January 16, 2003
    Inventors: John Y. L. Chung, Roger N. Farr, Guy R. Humphrey
  • N-(R)-(2-hydroxy-2-pyridine-3-yl-ethyl)-2-(4-nitro-phenyl)-acetamide
    Patent number: 5846791
    Abstract: Asymmetric bioreduction of a ketone substrate with yeast produces the corresponding (R)-alcohol of structure: ##STR1## a key intermediate in the synthesis of a .beta..sub.
    Type: Grant
    Filed: June 26, 1997
    Date of Patent: December 8, 1998
    Assignee: Merck & Co., Inc.
    Inventors: Michel M. Chartrain, John Y. L. Chung, Christopher Roberge
  • Process for N-Boc-N-(R)-2(3-pyridyl)-2-hydroxy-ethyl)-N-2(4-aminophenyl)ethyl amine and 2-(4-aminophenyl)-N-2-(2(R)-hydroxy-2-phyridin-S-yl-ethyl)acetamide
    Patent number: 5792871
    Abstract: Compound 9 is prepared by a 9-step ##STR1## process in an overall yield of about 35% from 3-acetylpyridine. Compound 10 is prepared by a seven-step ##STR2## process in an overall yield of about 30% from 3-acetyl pyridine. These compounds are key intermediates in the synthesis of Compound 11, an important .beta.-3 agonist useful in the treatment of obesity and diabetes.
    Type: Grant
    Filed: June 26, 1997
    Date of Patent: August 11, 1998
    Assignee: Merck & Co., Inc.
    Inventors: Michel M. Chartrain, Christopher Roberge, John Y. L. Chung, Dalian Zhao
  • Pyridyl ethylation of lactam derivatives
    Patent number: 5686607
    Abstract: The invention is a highly efficient synthesis for making compounds of formula (iv) wherein R is C.sub.1-4 alkyl or benzyl; and R.sup.1, when present, is C.sub.1-4 alkyl, OH, O--C.sub.1-4 alkyl, or S--C.sub.1-4 alkyl; which are useful intermediates for making compounds such as those represented in formula (I).
    Type: Grant
    Filed: August 29, 1996
    Date of Patent: November 11, 1997
    Assignee: Merck & Co., Inc.
    Inventors: John Y. L. Chung, Dalian Zhao, David J. Mathre
  • Pyridyl ethylation of lactams
    Patent number: 5665882
    Abstract: The invention is a highly efficient synthesis for making compounds of formula: ##STR1## wherein n=0, 1, R is C.sub.1-4 alkyl or benzyl; andR.sup.1, when present, is C.sub.1-4 alkyl, OH, O--C.sub.1-4 alkyl or S--C.sub.1-4 alkyl. The process involves silane-mediated conjugation of 4-vinylpyridine to a substituted lactam.
    Type: Grant
    Filed: August 29, 1996
    Date of Patent: September 9, 1997
    Assignee: Merck & Co., Inc.
    Inventors: John Y. L. Chung, Dalian Zhao, James M. McNamara, David L. Hughes
  • Peptide analog type-B CCK receptor ligands
    Patent number: 5340802
    Abstract: Peptide analog type-B CCK receptor ligands or pharmaceutically-acceptable salts thereof, which are useful for treating central nervous system disorders, substance abuse, gastrointestinal disorders, endocrine disorders, eating-related disorders and for the treatment of shock, respiratory and cardiocirculatory insufficiencies.
    Type: Grant
    Filed: January 29, 1993
    Date of Patent: August 23, 1994
    Assignee: Abbott Laboratories
    Inventors: Kazumi Shiosaki, Alex M. Nadzan, David S. Garvey, Youe-Kong Shue, Mark S. Brodie, Mark W. Holladay, John Y.-L. Chung, Michael D. Tufano, Paul D. May
  • Aryl thiopyrano[4,3,2-cd]indoles as inhibitors of leukotriene biosynthesis
    Patent number: 5314898
    Abstract: Compounds having the formula I: ##STR1## are inhibitors of the 5-lipoxygenase enzyme and inhibitors of leukotriene biosynthesis. These compounds are useful as anti-asthmatic, anti-allergic, anti-inflammatory, and cytoprotective agents. They are also useful in treating angina, cerebral spasm, glomerular nephritis, hepatitis, endotoxemia, psoriasis, uveitis, and allograft rejection and in preventing the formation of atherosclerotic plaques.
    Type: Grant
    Filed: June 29, 1992
    Date of Patent: May 24, 1994
    Assignees: Merck & Co., Inc., Merck Frosst Canada Inc.
    Inventors: John Y. L. Chung, Robert A. Reamer, Yves Girard, Pierre Hamel
  • Process for preparing fibrinogen receptor antagonists
    Patent number: 5312923
    Abstract: The invention is a highly efficient synthesis for making compounds of the formula: ##STR1## wherein: R.sup.1 is a six membered saturated or unsaturated heterocyclic ring containing one or two heteroatoms wherein the heteroatoms are N; or NR.sup.6, wherein R.sup.6 is H or C.sub.1-10 alkyl;m is an integer from two to six; andR.sup.4 is aryl, C.sub.1-10 alkyl, or C.sub.4-10 aralkyl.
    Type: Grant
    Filed: February 16, 1993
    Date of Patent: May 17, 1994
    Assignee: Merck & Co., Inc.
    Inventors: John Y. L. Chung, David L. Hughes, Dalian Zhao
  • Aza-spirocyclic compounds that enhance cholinergic neurotransmission
    Patent number: 5221675
    Abstract: Aza-spirocyclic compounds of formula (I) ##STR1## which enhance cortical cholinergic neurotransmission.
    Type: Grant
    Filed: February 26, 1991
    Date of Patent: June 22, 1993
    Assignee: Abbott Laboratories
    Inventors: John Y. L. Chung, David S. Garvey
  • Process for preparing fibrinogen receptor antagonists
    Patent number: 5206373
    Abstract: The invention is a highly efficient synthesis for making compounds of the formula: ##STR1## wherein: R.sup.1 is a six member saturated or unsaturated heterocyclic ring containing one or two heterocyclic atoms wherein the heteroatoms are N; or NR.sup.6, wherein R.sup.6 is H or C.sub.1-10 alkyl;m is an integer from two to six; andR.sup.4 is aryl, C.sub.1-10 alkyl, or C.sub.4-10 aralkyl.
    Type: Grant
    Filed: February 28, 1992
    Date of Patent: April 27, 1993
    Assignee: Merck & Co., Inc.
    Inventors: John Y. L. Chung, David L. Hughes, Dalian Zhao