Patents by Inventor Lyndon C. Xavier

Lyndon C. Xavier 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).

  • Boronic acid compound
    Patent number: 5618934
    Abstract: The present invention is directed to a compound represented by the structural formula: ##STR1## wherein Z-- represents a negatively charged counterion.
    Type: Grant
    Filed: February 27, 1995
    Date of Patent: April 8, 1997
    Assignee: Merck & Co., Inc.
    Inventors: Ann E. DeCamp, Edward J. J. Grabowski, Mark A. Huffman, Lyndon C. Xavier, Nobuyoshi Yasuda, Guo-Jie Ho, David J. Mathre
  • Preparation of 2-aryl carbapenems via a boronic acid coupling reaction
    Patent number: 5442057
    Abstract: The present invention is directed to a process of making 2-Aryl Carbapenems of Formula 1 from a compound of formula 2.
    Type: Grant
    Filed: April 12, 1994
    Date of Patent: August 15, 1995
    Inventors: Ann Decamp, Ulf H. Dolling, Yulan Li, Dale L. Rieger, Nobuyoshi Yasuda, Lyndon C. Xavier
  • Preparation of 2-aryl carbapenems
    Patent number: 5442056
    Abstract: The present invention is directed to a process of making 2-aryl carbapenems of formula 1 from a compound of formula A.
    Type: Grant
    Filed: May 17, 1994
    Date of Patent: August 15, 1995
    Assignee: Merck & Co., Inc.
    Inventors: Ann E. DeCamp, Edward J. J. Grabowski, Mark A. Huffman, Lyndon C. Xavier, Nobuyoshi Yasuda
  • Boron containing intermediates useful in the preparation of carbapenems
    Patent number: 5338875
    Abstract: The present invention is directed to intermediates of the following formula which are useful in the preparation of Carbapenem-antibiotics ##STR1##
    Type: Grant
    Filed: November 19, 1992
    Date of Patent: August 16, 1994
    Assignee: Merck & Co., Inc.
    Inventors: Ann DeCamp, Ulf H. Dolling, Yulan Li, Dale L. Rieger, Nobuyoshi Yasuda, Lyndon C. Xavier
  • Chiral catalysts for reduction of ketones and process for their preparation
    Patent number: 5264585
    Abstract: The chiral catalyst of general structure 1, or its enantiomer ##STR1## is prepared by treating the corresponding N-carboxy anhydride of structure 2 ##STR2## with an aryl metal, especially a phenyl metal such as an aryl magnesium halide, aryl lithium, aryl zinc or aryl cesium, to form a 1,1-diaryl- methanol of structure 3 ##STR3## followed by treatment with a compound of structure, 4 ##STR4## The catalyst, wherein R is aromatic, is novel and in some cases superior to the catalyst wherein R is alkyl or aralkyl in directing the chirality of diborane, borane-dimethyl sulfide or borane-tetrahydrofuran reductions of ketones to secondary alcohols.
    Type: Grant
    Filed: October 26, 1992
    Date of Patent: November 23, 1993
    Assignee: Merck & Co., Inc.
    Inventors: Thomas J. Blacklock, Todd K. Jones, David J. Mathre, Lyndon C. Xavier
  • Chiral boron catalysts for reduction of ketones and process for their preparation
    Patent number: 5189177
    Abstract: The chiral catalyst of general structure 1, or its enantiomer ##STR1## is prepared by treating the corresponding N-carboxy anhydride of structure 2 ##STR2## with an aryl metal, especially a phenyl metal such as an aryl magnesium halide, aryl lithium, aryl zinc or aryl cesium, to form a 1,1-diaryl- methanol of structure 3 ##STR3## followed by treatment with a compound of structure, 4 ##STR4## The catalyst, wherein R is aromatic, is novel and in some cases superior to the catalyst wherein R is alkyl or aralkyl in directing the chirality of diborane, borane-dimethyl sulfide or borane-tetrahydrofuran reductions of ketones to secondary alcohols.
    Type: Grant
    Filed: July 15, 1991
    Date of Patent: February 23, 1993
    Assignee: Merck & Co., Inc.
    Inventors: Thomas J. Blacklock, Todd K. Jones, David J. Mathre, Lyndon C. Xavier
  • Enantiospecific synthesis of S-(+)-5,6-dihydro-4-(R-amino)-4H-thieno(2,3-b)thiopyran-2-sulfonamide-7, 7-dioxide
    Patent number: 5157129
    Abstract: 5,6-Dihydro-4-(R-amino)-4H-thieno[2,3-b]-thiopyran-2-sulfonamide-7,7-dioxid e is a potent carbonic anhydrase inhibitor useful in the treatment of ocular hypertension and glaucoma. The S-(+)-enantiomer of that compound, the more active enantiomer, is prepared by a process involving an intermediate step of an enantioselective reduction of a carbonyl group employing an oxazaborolidine chiral catalyst.
    Type: Grant
    Filed: April 18, 1990
    Date of Patent: October 20, 1992
    Assignee: Merck & Co., Inc.
    Inventors: Thomas J. Blacklock, Todd K. Jones, Edward J. J. Grabowski, David J. Mathre, Julie J. Mohan, Paul Sohar, F. Edward Roberts, Lyndon C. Xavier
  • Arylation process for preparation of chiral catalysts for ketone reduction
    Patent number: 5039802
    Abstract: The chiral catalyst of general structure 1, or its enantiomer ##STR1## is prepared by treating the corresponding N-carboxy anhydride of structure 2 ##STR2## with an aryl metal, especially a phenyl metal such as an aryl magnesium halide, aryl lithium, aryl zinc or aryl cesium, to form a 1,1-diaryl-methanol of structure 3 ##STR3## followed by treatment with a compound of structure, 4 ##STR4## The catalyst, wherein R is aromatic, is novel and in some cases superior to the catalyst wherein R is alkyl or aralkyl in directing the chirality of borane-dimethyl sulfide reductions of ketones to secondary alcohols.
    Type: Grant
    Filed: April 18, 1990
    Date of Patent: August 13, 1991
    Assignee: Merck & Co., Inc.
    Inventors: Thomas J. Blacklock, Todd K. Jones, David J. Mathre, Lyndon C. Xavier