Patents by Inventor Keizo Tomuro

Keizo Tomuro 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 for optical resolution of DL-cysteine and (R,S)-1-(1-naphthyl) ethylamine
    Patent number: 4736060
    Abstract: Method for optical resolution of DL-cysteine by (1) reacting DL-cysteine with formaldehyde to prepare DL-thiazolidine-4-carboxylic acid (DL-TCA), (2) forming diastereomer salts of D-TCA and of L-TCA by reacting DL-TCA with an optically active 1-(1-naphthyl)ethylamine, (3) separating said diastereomer salts by difference of the solubilities thereof in a solvent, (4) recovering D-TCA from said diastereomer salt of D-TCA and finally obtain D-cysteine, and recovering L-TCA from said diastereomer salt of L-TCA and finally obtain L-cysteine.
    Type: Grant
    Filed: August 1, 1986
    Date of Patent: April 5, 1988
    Assignee: Nippon Rikagakuyakuhin Co., Ltd.
    Inventors: Keizo Tomuro, Yoshiharu Tamura, Yoko Morimoto, Shigeyoshi Katoh