Patents by Inventor Hisao Akiyama

Hisao Akiyama 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 synthesis of optically active thiolactones
    Patent number: 4014895
    Abstract: A new method for the production of intermediates in the synthesis of an optically active biotin, which comprises reacting a dicarboxylic acid of the formula: ##SPC1##Or its reactive derivative with an optically active primary amine, reducing the resulting trione with a metal hydride, hydrolyzing the resultant amide-alcohol and treating the thus produced lactone with a thiolactonating agent to give a thiolactone of the formula: ##SPC2##, the said trione and amide-alcohol being respectively novel and representable by the formulae: ##SPC3##
    Type: Grant
    Filed: December 13, 1974
    Date of Patent: March 29, 1977
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Yasuhiko Aoki, Hiroyuki Suzuki, Hisao Akiyama, Shigeru Okano
  • Process for preparing hexahydrothieno[3,4-d]imidazole-2,4-diones
    Patent number: 3931219
    Abstract: In the conversion of a hexahydrofuro[3,4-d]-imidazole-2,4-dione compound into the corresponding hexahydrothieno[3,4-d]imidazole-2,4-dione compound, an improved process which comprises reacting the starting hexahydrofuro[3,4-d]imidazole-2,4-dione compound with a dithiocarbamate.
    Type: Grant
    Filed: September 27, 1974
    Date of Patent: January 6, 1976
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Yasuhiko Aoki, Hiroyuki Suzuki, Hisao Akiyama, Shigeru Okano