Patents by Inventor Gerhard Shiefer

Gerhard Shiefer 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).

  • Synthesis of substituted 4-amino-pyrimidines
    Patent number: 8252927
    Abstract: The present invention is directed to a process for the manufacture of compounds of formula IV wherein R1 is an amino protecting group, and R2 is hydrogen or C1-10 alkyl, comprising a) reacting a compound of formula Ia, wherein M+ is a cation, preferably selected from the group consisting of Li+, Na+, K+, ½ Mg2+ and ½ Zn2+, (formula 1a) with an ammonium salt NH4+X?, wherein X? is an anion, preferably selected from the group consisting of chloride, bromide, sulfate and acetate, in a solvent to a compound of formula II b) reacting a compound of formula II with a nitrile R2—CN in the presence of a base to a compound of formula IV. The present invention is further directed to compounds of formula II and their use for the manufacture of vitamin B1.
    Type: Grant
    Filed: July 22, 2009
    Date of Patent: August 28, 2012
    Assignee: DSM IP Assets B.V.
    Inventors: Reinhard Karge, Ulla Letinois, Gerhard Shiefer
  • NOVEL SYNTHESIS OF SUBSTITUTED 4-AMINO-PYRIMIDINES
    Publication number: 20110178300
    Abstract: The present invention is directed to a process for the manufacture of compounds of formula IV wherein R1 is an amino protecting group, and R2 is hydrogen or C1-10 alkyl, comprising a) reacting a compound of formula Ia, wherein M+ is a cation, preferably selected from the group consisting of Li+, Na+, K+, ms, ½ Mg2+ and ½ Zn2+, (formula 1a) with an ammonium salt NH4X?, wherein X? is an anion, preferably selected from the group consisting of chloride, bromide, sulfate and acetate, in a solvent to a compound of formula II b) reacting a compound of formula II with a nitrile R2—CN in the presence of a base to a compound of formula IV. The present invention is further directed to compounds of formula II and their use for the manufacture of vitamin B1.
    Type: Application
    Filed: July 22, 2009
    Publication date: July 21, 2011
    Inventors: Reinhard Karge, Ulla Letinois, Gerhard Shiefer