Patents by Inventor Shoko Takebayashi

Shoko Takebayashi 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).

  • Method of racemization of optically active tetrahydrofuran-2-carboxylic acid
    Patent number: 4950772
    Abstract: Disclosed is a method of racemization of optically active tetrahydrofuran-2-carboxylic acid. (+)-Tetrahydrofuran-2-carboxylic acid is useful as a side chain intermediate of the antibiotics of penem series, and is prepared by optical resolution of racemic compound. The remaining (+)-isomer should be racemized and reused as the material for further optical resolution. The racemization can be, in accordance with the present invention, carried out by heating the optically active tetrahydrofuran-2-carboxylic acid to a temperature of 100.degree. C. or higher in the presence of a strong base.
    Type: Grant
    Filed: October 31, 1989
    Date of Patent: August 21, 1990
    Assignee: Yamakawa Chemical Industry Co., Ltd.
    Inventors: Hiroyuki Nohira, Shoko Takebayashi, Atsushi Yuzawa, Masami Yajima