Patents by Inventor Hiromitsu Saito

Hiromitsu Saito 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).

  • Pyrroloindole derivatives
    Patent number: 5187186
    Abstract: DC-88A derivatives represented by the general formula: ##STR1## wherein X represents hydrogen or CO.sub.2 R.sup.1 (in which R.sup.1 represents hydrogen, a straight-chain or branched alkyl having 1 to 4 carbon atoms, allyl, or benzyl); and ##STR2## have an excellent anti-tumor activity and are useful as anti-tumor agents.
    Type: Grant
    Filed: September 6, 1991
    Date of Patent: February 16, 1993
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Yutaka Kanda, Youichi Uosaki, Hiromitsu Saito, Hiroshi Sano, Eiji Kobayashi, Makoto Morimoto, Satoru Nagamura
  • UCN-1028D derivatives
    Patent number: 5140044
    Abstract: A UCN-1028D derivative represented by the formula: ##STR1## has protein kinase C inhibitory activity and is expected to be used as an active ingredient in anti-tumor agents, etc.
    Type: Grant
    Filed: March 27, 1990
    Date of Patent: August 18, 1992
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Teruo Kishi, Hiromitsu Saito, Hiroshi Sano, Isami Takahashi, Tatsuya Tamaoki
  • DC-89 compounds and process for their preparation
    Patent number: 5138059
    Abstract: Novel DC-89 compounds represented by the general formula: ##STR1## wherein X represents a single bond or --CH.sub.2 --; and when X represents a single bond, Y represents --CH.sub.2 Br or --CH.sub.2 Cl and when X represents --CH.sub.2 --, Y represents Br, are obtained by the present invention. The compounds have antibacterial and anti-tumor activity.
    Type: Grant
    Filed: July 17, 1989
    Date of Patent: August 11, 1992
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Keiichi Takahashi, Michio Ichimura, Shigeo Katsumata, Tatsuhiro Ogawa, Makoto Morimoto, Tadashi Ashizawa, Masaji Kasai, Kenichi Muroi, Hiromitsu Saito, Hiroshi Sano, Toru Yasuzawa
  • DC-88A derivatives useful as antitumor agents
    Patent number: 5117006
    Abstract: A DC-88A derivative represented by general formula: ##STR1## wherein ##STR2## represents ##STR3## has an excellent antitumor activity and is useful as an anti-tumor agent.
    Type: Grant
    Filed: May 15, 1991
    Date of Patent: May 26, 1992
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Hiromitsu Saito, Masaji Kasai, Makoto Morimoto, Eiji Kobayashi, Yoichi Uosaki, Yutaka Kanda, Hiroshi Sano
  • DC-88A derivatives
    Patent number: 5084468
    Abstract: A novel DC-88A derivative represented by general formula: ##STR1## wherein ##STR2## represents ##STR3## has an excellent antitumor activity and is useful as an antitumor agent.
    Type: Grant
    Filed: August 10, 1989
    Date of Patent: January 28, 1992
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Hiromitsu Saito, Masaji Kasai, Makoto Morimoto, Eiji Kobayashi, Yoichi Uosaki, Yutaka Kanda, Hiroshi Sano
  • DC-52 derivatives
    Patent number: 5071984
    Abstract: Disclosed are DC-52 derivatives represented by the formula: ##STR1## wherein each of R.sup.1 and R.sup.2 independently represents hydrogen or hydroxyl, X represents hydroxyl and Y represents cyano and Z represents carboxyl or hydroxymethyl, or pharmacologically acceptable salts thereof. The DC-52 derivatives are useful as antitumor agents.
    Type: Grant
    Filed: November 14, 1990
    Date of Patent: December 10, 1991
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Hiromitsu Saito, Akira Sato, Masaji Kasai, Makoto Morimoto, Tadashi Ashizawa
  • Pyrroloindole derivatives related to DC-88A compound
    Patent number: 5070092
    Abstract: DC-88A derivatives represented by the general formula: ##STR1## wherein X represents hydrogen or CO.sub.2 R.sup.1 (in which R.sup.1 represents hydrogen, a straight-chain or branched alkyl having 1 to 4 carbon atoms, allyl, or benzyl); and ##STR2## have an excellent anti-tumor activity and are useful as anti-tumor agents.
    Type: Grant
    Filed: June 29, 1990
    Date of Patent: December 3, 1991
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Yutaka Kanda, Youichi Uosaki, Hiromitsu Saito, Hiroshi Sano, Eiji Kobayashi, Makoto Morimoto, Satoru Nagamura
  • Hydroxamic acid derivatives and use thereof in combatting lipoxygenase-mediated diseases
    Patent number: 5011854
    Abstract: A hydroxamic acid compound represented by the general formula (I) or a salt thereof; ##STR1## wherein R.sup.1 represents a hydrogen atom, or a substituted or unsubstituted alkanoyl group, R.sup.2 represents an unsubstituted alkanoyl, substituted lower alkanoyl or substituted lower alkyl group, and m represents an integer of 3 to 7, which are useful for the prevention and/or treatment of diseases caused by lipoxygenase-mediated metablites.
    Type: Grant
    Filed: December 7, 1989
    Date of Patent: April 30, 1991
    Assignee: Kyowa Hakko Kogyo Co. Ltd.
    Inventors: Mitsuru Takahashi, Shigeto Kitamura, Hiroshi Kase, Masaji Kasai, Isao Kawamoto, Takao Iida, Hiroshi Sano, Hiromitsu Saito, Koji Yamada, Chikara Murakata
  • DC-88A derivatives
    Patent number: 5008271
    Abstract: A novel DC-88A derivative represented by general formula: ##STR1## wherein ##STR2## represents ##STR3## has an excellent antitumor activity and is useful as an antitumor agent.
    Type: Grant
    Filed: October 18, 1989
    Date of Patent: April 16, 1991
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Yutaka Kanda, Tohru Yasuzawa, Hiromitsu Saito, Hiroshi Sano, Eiji Kobayashi, Makoto Morimoto
  • DC-52 derivatives
    Patent number: 4992551
    Abstract: Disclosed are DC-52 derivatives represented by the formula: ##STR1## wherein each of R.sup.1 and R.sup.2 independently represents hydrogen or hydroxyl, X represents hydroxyl and Y represents cyano and Z represents carboxyl or hydroxymethyl, or pharmacologically acceptable salts thereof. The DC-52 derivatives are useful as antitumor agents.
    Type: Grant
    Filed: November 13, 1989
    Date of Patent: February 12, 1991
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Hiromitsu Saito, Akira Sato, Masaji Kasai, Makoto Morimoto, Tadashi Ashizawa
  • Anti-tumor DC-52 derivatives
    Patent number: 4946957
    Abstract: The present invention relates to novel derivatives of DC-52 represented by the following formula (I): ##STR1## [wherein X is chlorine, bromine, iodine, hydroxyl, formyl, hydroxyiminomethyl, cyano, nitro, amino or lower alkanoylamino; and Y is hydroxyl and Z is cyano, or Y and Z represent --O-- in the form of --Y--Z--]. These compounds and pharmacologically acceptable salts thereof have high anti-tumor activity.
    Type: Grant
    Filed: August 30, 1989
    Date of Patent: August 7, 1990
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Hiromitsu Saito, Yoichi Uosaki, Akira Sato, Tadashi Hirata, Makoto Morimoto, Tadashi Ashizawa
  • Anti-tumor DC-52 compounds
    Patent number: 4879386
    Abstract: The present invention relates to novel derivatives of DC-52 represented by the following formula (I): ##STR1## ps [wherein X is chlorine, bromine, iodine, hydroxyl, formyl, hydroxyiminomethyl, cyano, nitro, amino or lower alkanoylamino; and Y is hydroxyl and Z is cyano, or Y and Z represent --O-- in the form of --Y--Z--]. These compounds and pharmacologically acceptable salts thereof have high anti-tumor activity.
    Type: Grant
    Filed: May 25, 1988
    Date of Patent: November 7, 1989
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Hiromitsu Saito, Yoichi Uosaki, Akira Sato, Tadashi Hirata, Makoto Morimoto, Tadashi Ashizawa
  • DC-52 derivatives and their antitumor use
    Patent number: 4822882
    Abstract: Compounds represented by the following formula or by the corresponding hydroquinone type formula: ##STR1## in which R.sup.1 and R.sup.2 are independently hydrogen, lower alkoxy, azido, amino, lower alkylamino, di-lower alkylamino, cyclic amino, lower alkylthio or unsubstituted or substituted arylthio; and X represents hydroxyl and Y represents cyano or X and Y together represents --O-- in the form of --X--Y--, have an excellent antitumor activity.
    Type: Grant
    Filed: September 29, 1987
    Date of Patent: April 18, 1989
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Hiromitsu Saito, Yoichi Uosaki, Akira Sato, Tadashi Hirata, Makoto Morimoto, Tadashi Ashizawa
  • Cyclopentenone compound and process for production thereof
    Patent number: 4618687
    Abstract: A cyclopentenone compound represented by the following formula: ##STR1## has an antitumor effect and can be produced from the antibiotic XK-213.
    Type: Grant
    Filed: April 18, 1985
    Date of Patent: October 21, 1986
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Tadashi Hirata, Hiromitsu Saito, Makoto Morimoto
  • Cephalosporin analogs
    Patent number: 4343943
    Abstract: Novel cephalosporin analogs and intermediates therefor are useful as antibiotics. Methods for producing the compounds are provided.
    Type: Grant
    Filed: June 25, 1979
    Date of Patent: August 10, 1982
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Tadashi Hirata, Hiromitsu Saito, Nobuhiro Nakamizo
  • Cephalosporin analogs and methods for production thereof
    Patent number: 4291164
    Abstract: Novel cephalosporin analogs are disclosed which are useful as intermediates in the production of other compounds having antibacterial activity. Methods for producing the compounds are also disclosed.
    Type: Grant
    Filed: March 23, 1979
    Date of Patent: September 22, 1981
    Assignee: Kyowa Hakko Kogyo Co., Ltd.
    Inventors: Tadashi Hirata, Takehiro Ogasa, Hiromitsu Saito, Nobuhiro Nakamizo