Patents by Inventor Hirofumi Terasawa

Hirofumi Terasawa 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).

  • Hexa-cyclic camptothecin derivatives
    Patent number: 4939255
    Abstract: A novel hexa-cyclic compound, a derivative of camptothecin, of the general formula: ##STR1## The compound is prepared from an aminoketone compound and a pyranoindolizine compound through Friedlaender reaction. It has an excellent antitumor activity and a high degree of safety, and can be applied as an antitumor medicine for curing tumors of various kinds.
    Type: Grant
    Filed: June 16, 1988
    Date of Patent: July 3, 1990
    Assignees: Daiichi Pharmaceutical Co., Ltd., Kabushiki Kaisha Yakult Honsha
    Inventors: Hiroaki Tagawa, Masamichi Sugimori, Hirofumi Terasawa, Akio Ejima, Satoru Ohsuki
  • Certain pyrano (3,4-f)-indolizine derivatives
    Patent number: 4778891
    Abstract: A pyranoindolizine derivative represented by the following general formula (I): ##STR1## wherein R means a hydrogen atom or hydroxyl group and Q denotes >C.dbd.O or ##STR2## with a proviso that Q is other than >C.dbd.O when R is a hydrogen atom. Its preparation process is also described.
    Type: Grant
    Filed: October 16, 1986
    Date of Patent: October 18, 1988
    Assignees: Daiichi Seiyaku Co., Ltd., Kabushiki Kaisha Yakult Honsha
    Inventors: Hiroaki Tagawa, Hirofumi Terasawa, Akio Ejima