Patents by Inventor Shuichi Nakatsuyama

Shuichi Nakatsuyama 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).

  • Peptide substrates for determination of enzyme activity
    Patent number: 5116941
    Abstract: Compounds represented by the following formula: ##STR1## wherein A.sub.1 and A.sub.2 each represents a specific amino acid residue, are excellent as substrates for determination of enzyme activity such as trypsin, etc.
    Type: Grant
    Filed: July 12, 1989
    Date of Patent: May 26, 1992
    Assignee: Nitto Boseki Co., Ltd.
    Inventors: Shuichi Nakatsuyama, Yoshio Nakamura, Katsumasa Kuroiwa, Takeshi Nagasawa
  • Substrates for determination of enzyme activity and intermediates for synthesis of the substrates as well as process for producing the intermediates
    Patent number: 5115099
    Abstract: Novel compounds represented by the following formula: ##STR1## wherein A represents a specific amino acid residue are excellent as substrates for determination of enzyme activity such as trypsin, etc. The compounds can be synthesized from novel arginyl-3-tert-alkyloxycarbonyl-4-nitroanilides by a novel process comprising a selective deprotection step whereby the protecting group on the .alpha.-amine group of arginine is removed in the presence of a hydrochloric acid, acetic acid and dimethylformamide mixture, but a tert-alkyl protecting group on the --COOH group of the nitroanilide ring is not removed by this step.
    Type: Grant
    Filed: June 13, 1989
    Date of Patent: May 19, 1992
    Assignee: Nitto Boseki Co., Ltd.
    Inventors: Katsumasa Kuroiwa, Hitoshi Matsuura, Katsuhiro Katayama, Shuichi Nakatsuyama, Takeshi Nagasawa, Koji Endo
  • Arginyl-3-carboxy-4-hydroxyanilide
    Patent number: 4584398
    Abstract: Novel arginyl-3-carboxy-4-hydroxyanilide of the formula ##STR1## and acid addition salts thereof are of use as starting materials for preparing chromophoric and fluorescent substrates for measurement of enzyme activity.
    Type: Grant
    Filed: February 1, 1985
    Date of Patent: April 22, 1986
    Assignee: Nitto Boseki Co., Ltd.
    Inventors: Katsumasa Kuroiwa, Shuichi Nakatsuyama, Takeshi Nagasawa
  • Process for producing arginyl-p-nitroanilide
    Patent number: 4564695
    Abstract: An N.sup..alpha. -protected-N.sup.G -protected-arginyl-p-nitro-anilide with high purity can be produced in high yield by reacting an N.sup..alpha. -protected-N.sup.G -protected-arginine with p-nitroaniline in pyridine in the presence of a condensing agent.
    Type: Grant
    Filed: September 13, 1984
    Date of Patent: January 14, 1986
    Assignee: Nitto Boseki Co., Ltd.
    Inventors: Katsumasa Kuroiwa, Shuichi Nakatsuyama, Takeshi Nagasawa