Patents by Inventor Shousuke Nagai

Shousuke Nagai 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).

  • Preparation process of .beta.-chloroalanine
    Patent number: 4484003
    Abstract: .beta.-Chloroalanine is prepared by reacting in an aqueous medium an aziridine-2-carboxylate with hydrogen chloride in an amount of 2.0-5.0 moles per mole of the aziridine-2-carboxyalte and causing the thus-formed .beta.-chloroalanine to selectively crystallize out from the liquid reaction mixture. Since the solution recovered after the isolation of the crystallized .beta.-chloroalanine still contains .beta.-chloroalanine and by-produced .alpha.-chloro-.beta.-alanine dissolved therein, they may be converted into an aziridine-2-carboxylate by treating them with a base to recirculate it for reuse.
    Type: Grant
    Filed: December 29, 1982
    Date of Patent: November 20, 1984
    Assignee: Mitsui Toatsu Chemicals, Incorporated
    Inventors: Masaharu Ohoka, Toshio Katoh, Ryuichi Mita, Nobuyuki Kawashima, Chojiro Higuchi, Nobuhiro Kawashima, Akihiro Yamaguchi, Shousuke Nagai, Takao Takano
  • Production process of DL-cystein
    Patent number: 4453008
    Abstract: DL-cystein is produced by reacting a .beta.-halogenoalanine with a trithiocarbonate to obtain the mono(aminocarboxyethyl) ester of trithiocarbonate and then subjecting the ester to acid decomposition. The above process requires mild reaction conditions, is easy to carry out its reactions and can afford DL-cystein with high yield. It is thus an excellent production process of DL-cystein from the industrial viewpoint.
    Type: Grant
    Filed: January 14, 1983
    Date of Patent: June 5, 1984
    Assignee: Mitsui Toatsu Chemicals, Inc.
    Inventors: Ryuichi Mita, Masaharu Ohoka, Chojiro Higuchi, Toshio Katoh, Nobuyuki Kawashima, Akihiro Yamaguchi, Shousuke Nagai, Takao Takano