Patents by Inventor David Ryckman

David Ryckman 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: 6175024
    Abstract: A method of preparing an ester of a carboxylic acid functionalized with a moiety selected from the group consisting of halides, sulfonates, ethers, hydroxyl, amines, and aldehydes, said method comprising: (a) providing either a carboxylic acid having a vinyl group or an ester thereof; (b) functionalizing the vinyl carbon closest to the carboxyl group with said moiety, wherein said functionalizing comprises cleaving said vinyl group.
    Type: Grant
    Filed: March 3, 1999
    Date of Patent: January 16, 2001
    Assignee: AlliedSignal Inc.
    Inventors: William J. Boyle, Jr., Indira Reddy, Zhenrong Qian, Heng Eric Su, David Ryckman
  • Patent number: 6054622
    Abstract: A method for the preparation of aromatic hydroxythiols including oxidizing an aromatic aminothiol to form an aminodisulfide compound; forming a bis-diazonium salt of the aminodisulfide compound; and reacting the bis-diazonium salt with water to form an aromatic hydroxyldisulfide compound, which is then reduced to the hydroxythiol. New bis-diazonium aromatic disulfide compounds are also disclosed.
    Type: Grant
    Filed: December 18, 1998
    Date of Patent: April 25, 2000
    Assignee: AlliedSignal Inc
    Inventors: Mingbao Zhang, David Ryckman, Eric MacMillan
  • Patent number: 6054623
    Abstract: A method for the preparation of hydroxythiol compounds by reacting a hydroxyl-protected halide compound having the structure:X--R--OPgwith magnesium in a Grignard-suitable solvent to form a hydroxyl-protected magnesium halide compound, wherein R is selected from substituted or unsubstituted aliphatic radicals, substituted or unsubstituted cyclic aliphatic radicals, substituted or unsubstituted aromatic radicals, substituted or unsubstituted araliphatic radicals and substituted or unsubstituted heterocyclic radicals; Pg is a protecting group; and X is selected from the group consisting of F, Cl, Br and I; then reacting said hydroxyl-protected magnesium halide compound with sulfur in the Grignard-suitable solvent to form a hydroxyl-protected thiomagnesium halide compound; and hydrolyzing the protected hydroxyl group to form a hydroxythiomagnesium halide compound and converting the thiomagnesium halide to a thiol; wherein the protecting group is selected so that species formed by the de-protection of the protect
    Type: Grant
    Filed: December 18, 1998
    Date of Patent: April 25, 2000
    Assignee: AlliedSignal Inc.
    Inventors: David Ryckman, Mingbao Zhang, Guohua Chen
  • Patent number: 5734061
    Abstract: The invention is directed to an improved process for the preparation of spirocyclic lactams which utilizes diiodides in the spiro alkylation of lactams N-substituted with a tertiary amine group. The resultant spirocyclic lactams are useful in the production of various substituted azaspiranes which are useful as immunomodulatory agents.
    Type: Grant
    Filed: June 13, 1996
    Date of Patent: March 31, 1998
    Assignee: SmithKline Beecham Corporation
    Inventor: David Ryckman