Patents by Inventor Sho Tokumoto

Sho Tokumoto 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 producing 2-methylspiro(1,3-oxathiolane-5,3')quinuclidine
    Patent number: 5571918
    Abstract: A method for producing 2-methylspiro(1,3-oxathiolane-5,3')quinuclidine, which comprises reacting 3-hydroxy-3-mercaptomethylquinuclidine or a salt thereof and a carbonyl compound in the presence of a catalyst made of at least one member selected from the group consisting of tin halides, oxyacids of phosphorus, phosphorus oxyhalides and organic sulfonic acids, to produce cis-form 2-methylspiro(1,3-oxathiolane-5,3')quinuclidine or a salt thereof.
    Type: Grant
    Filed: May 11, 1995
    Date of Patent: November 5, 1996
    Assignee: Ishihara Sangyo Kaisha Ltd.
    Inventors: Koji Hayashi, Sho Tokumoto, Hiroshi Yoshizawa, Tatsuo Isogai, Masaru Kimura, Masahiko Sawaki, Takayoshi Ando, Isamu Katsuyama, Hayato Ariyoshi, Tadashi Nakamura