Patents by Inventor Sumio Yoshino

Sumio Yoshino 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).

  • Process for producing a 4,6-bis(difluoromethoxy)-2-alkylthiopyrimidine
    Patent number: 5071982
    Abstract: A process for producing a 4,6-bis(difluoromethoxy)-2-alkylthiopyrimidine, which comprises reacting a 2-alkylthiobarbituric acid and monochlorodifluoromethane in the presence of a base in an inert solvent, wherein, for a first reaction, after charging a part of the base, the rest of the base and the monochlorodifluoromethane are simultaneously introduced to obtain a mixture of a 4-difluoromethoxy-6-hydroxy-2-alkylthiopyrimidine and a 4,6-bis(difluoromethoxy)-2-alkylthiopyrimidine, and then, for a second reaction, to this mixture, the base and the monochlorodifluoromethane are again simultaneously introduced, or the base is charged first and then the monochlorodifluoromethane is introduced.
    Type: Grant
    Filed: July 26, 1990
    Date of Patent: December 10, 1991
    Assignees: Asahi Glass Co., Ltd., Ciba-Geigy AG, Kawaguchi Chemical Industry Company, Ltd.
    Inventors: Sumio Yoshino, Kazuyuki Watanabe, Mikio Akazawa