Patents by Inventor Yukio Chikui

Yukio Chikui 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).

  • Dihydrate crystals of etoposide-2-dimethylamino compound hydrochloride and a process for production thereof
    Patent number: 4997923
    Abstract: The present invention provides novel dihydrate crystals of etoposide-2-dimethylamino compound hydrochloride [4'-demethylepipodophillotoxin 9-(4,6-O-ethylidene-2-dimethylamino-2-deoxy-.beta.-D-glucopyranoside hydrochloride] used as a carcinostatic agent and a process for production thereof.
    Type: Grant
    Filed: November 13, 1989
    Date of Patent: March 5, 1991
    Assignee: Nippon Kayaku Kabushiki Kaisha
    Inventors: Takao Izawa, Tadashi Fujii, Yukio Chikui, Kazuo Ohtsuki
  • Process for producing etoposide
    Patent number: 4757138
    Abstract: The present invention relates to a process for producing etoposide by reacting a 4'-halogenoacetyl-4'-demethylepipodophyllotoxin-.beta.-D-2,3-di-O-halogeno acetyl-4,6-O-ethylideneglucoside represented by the general formula: ##STR1## wherein R.sub.1 and R.sub.2, which may be the same or different, represent each --COCHX.sub.2 or --COCX.sub.3, wherein X represents a halogen atom, with an alcohol, an amine, and/or ammonia to remove the halogenoacetyl groups.
    Type: Grant
    Filed: September 8, 1986
    Date of Patent: July 12, 1988
    Assignee: Nippon Kayaku Kabushiki Kaisha
    Inventors: Tadashi Fujii, Yukio Chikui