Patents by Inventor Yoshinobu Miyazawa

Yoshinobu Miyazawa 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 optically active cyanohydrins
    Patent number: 5900503
    Abstract: An optically active cyanohydrin represented by the following general formula (1): ##STR1## wherein each of R1 and R2 is a hydrogen atom or an amino-protecting group, and the configurations relating to the carbon atoms at the *2-position and *3-position are as follows: in the case of the carbon atom at the *2-position being in R-configuration, the carbon atom at the *3-position is in S-configuration, and in the case of the carbon atom at the *2-position being in S-configuration, the carbon atom at the *3-position is in R-configuration, can be efficiently produced by crystallizing one of the optically active cyanohydrins while treating a mixture of cyanohydrin diastereomers in the presence of an amine and an organic solvent to change the configuration relating to the carbon atom at the 2-position and thereby cause isomerization.
    Type: Grant
    Filed: May 11, 1998
    Date of Patent: May 4, 1999
    Assignee: Nippon Kayaku Kabushiki Kaisha
    Inventors: Yoshinobu Miyazawa, Taichi Koshigoe, Kouichi Ohkawa, Jouji Sekine, Shinichiro Saeki
  • Process for the preparation of etoposide phosphate and intermediate thereof
    Patent number: 5637680
    Abstract: An etoposide phosphate represented by the formula ##STR1## is prepared by blocking the hydroxyl groups of the saccharide moiety of etoposide with halogenoacetyl groups, thereafter phosphorylating the 4'-position, and removing the halogenoacetyl groups from the obtained phosphate in the presence of an amine. This process can give the objective etoposide phosphate in a higher yield than that of the prior art to enable the industrial mass-production thereof.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: June 10, 1997
    Assignee: Nippon Kayaku Kabushiki Kaisha
    Inventors: Yoshinobu Miyazawa, Hitoshi Sato, Hiroshi Yoshikawa, Kouichi Ohkawa, Noriko Tomiyoshi
  • Etoposide phosphate and preparative intermediates
    Patent number: 5606039
    Abstract: An etoposide phosphate represented by the formula (1): ##STR1## is prepared by blocking the hydroxyl groups of the saccharide moiety of etoposide with halogenoacetyl groups, thereafter phosphorylating the 4'-position, and removing the halogenoacetyl groups from the obtained phosphate in the presence of an amine.This process can give the objective etoposide phosphate in a higher yield than that of the prior art to enable the industrial mass-production thereof.
    Type: Grant
    Filed: March 27, 1995
    Date of Patent: February 25, 1997
    Assignee: Nippon Kayaku Kabushiki Kaisha
    Inventors: Yoshinobu Miyazawa, Hitoshi Sato, Hiroshi Yoshikawa, Kouichi Ohkawa, Noriko Tomiyoshi
  • Process for producing optically active valine
    Patent number: 4667054
    Abstract: This invention relates to a process for producing optically active valine, characterized by optically resolving DL-valine hydrochloride in a solvent containing an amine salt, a sulfonic acid or a carboxylic acid and isolating optically active valine after the decomposition of the obtained optically active valine hydrochloride.
    Type: Grant
    Filed: January 30, 1986
    Date of Patent: May 19, 1987
    Assignee: Nippon Kayaku Kabushiki Kaisha
    Inventors: Yoshinobu Miyazawa, Noriko Ooishi, Shigeru Aoki, Yasuhisa Tashiro
  • N-benzyloxycarbonyl-L-threonine amide hemihydrate
    Patent number: 4628111
    Abstract: The present invention relates to new easily filtrable, non-hygroscopic N-benzyloxycarbonyl-L-threonine amide hemihydrate.
    Type: Grant
    Filed: April 16, 1985
    Date of Patent: December 9, 1986
    Assignee: Nippon Kayaku Kabushiki Kaisha
    Inventors: Akihiro Mashiba, Kazuteru Hagita, Yoshinobu Miyazawa, Tetsushi Saino, Yasuhisa Tashiro