Patents by Inventor Hiroshi Itazaki

Hiroshi Itazaki 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).

  • Aldose reductase inhibitor obtained from Crucibulum sp. RF-3817
    Patent number: 5324742
    Abstract: The present invention relates to a novel aldose reductase inhibitor of the formula: ##STR1## wherein X is methylene or carbonyl;R is ##STR2## R.sup.1, R.sup.2, R.sup.3, and R.sup.4 each is hydrogen or lower alkyl, to a method for producing the inhibitor by culturing Crucibulum sp. RF-3817 or its variants, and to an agent for inhibiting an aldose reductase comprising the inhibitor.
    Type: Grant
    Filed: May 8, 1991
    Date of Patent: June 28, 1994
    Assignee: Shionogi & Co., Ltd.
    Inventors: Tadashi Yoshida, Toshiyuki Kato, Yoshimi Kawamura, Koichi Matsumoto, Hiroshi Itazaki
  • Immunosuppressive agent
    Patent number: 5314911
    Abstract: The present invention relates to a compound represented by the formula I: ##STR1## which was isolated from the culture of Streptomyces prunicolor PA-48153 and has biological activity such as immunosuppressive activity, antitumor activity and antifungal activity.
    Type: Grant
    Filed: March 12, 1993
    Date of Patent: May 24, 1994
    Assignee: Shionogi Seiyaku Kabushiki Kaisha
    Inventors: Tadashi Yoshida, Kenzo Koizumi, Yoshimi Kawamura, Koichi Matsumoto, Hiroshi Itazaki
  • Aldose reductase inhibitor
    Patent number: 5284870
    Abstract: The present invention relates to an aldose reductase inhibitor represented by the formula: ##STR1## wherein R.sub.1 is (CH.sub.2).sub.2 COOH and R.sub.2 is phenyl or p-hydroxyphenyl, or R.sub.1 and R.sub.2 are combined together to form a group of the formula: ##STR2## which was isolated from the fermentation products of Chaetomella circinoseta RF-3192.
    Type: Grant
    Filed: February 9, 1993
    Date of Patent: February 8, 1994
    Assignee: Shionogi Seiyaku Kabushiki Kaisha
    Inventors: Tadashi Yoshida, Toshiyuki Kato, Yoshimi Kawamura, Koichi Matsumoto, Hiroshi Itazaki
  • Phospholipase A.sub.2 inhibitor
    Patent number: 5120647
    Abstract: A compound of the formula (I): ##STR1## wherein R.sup.1, R.sup.2, and R.sup.3 are --COOR.sup.4, --COOR.sup.5, and --COOR.sup.6, respectively; R.sup.4, R.sup.5, and R.sup.6 each is hydrogen, lower alkyl, or alkali metal; W is hydroxyl; X, Y, and Z each is hydrogen or hydroxyl; a dotted line indicates the presence or absence of a single bond; or where W/R.sup.3, X/R.sup.1, and/or Z/R.sup.3 may be combined together, a lactone is formed, which compound is useful as a phospholipase A.sub.2 inhibitor. Process for the production of the compound (I) and a cell culture of a microorganism Circinotrichum falcatisporum RF-641 producing the same are also provided.
    Type: Grant
    Filed: November 26, 1990
    Date of Patent: June 9, 1992
    Assignee: Shionogi & Co., Ltd.
    Inventors: Tadashi Yoshida, Hiroshi Itazaki, Hitoshi Arita, Yoshimi Kawamura, Koichi Matsumoto
  • Cyclic tetrapeptide and process for preparing the same
    Patent number: 5112944
    Abstract: A cyclic tetrapeptide having the formula (I): ##STR1## wherein n is 4 or 3 and a process for preparing the above cyclic tetrapeptide. The cyclic tetrapeptide of the present invention inhibits transformation of cells caused by oncogenes and possesses activities for recovering to a normal cell and for inhibiting proliferation of carcinoma cells. Therefore, the cyclic tetrapeptide of the present invention is useful for an active ingredient of an antitumor agent.
    Type: Grant
    Filed: June 12, 1990
    Date of Patent: May 12, 1992
    Assignee: Shionogi & Co., Ltd.
    Inventors: Kenji Sugita, Hiroshi Itazaki, Koichi Matsumoto, Yoshimi Kawamura
  • Phospholipase A.sub.2 inhibitor
    Patent number: 5099034
    Abstract: A compound of the formula (I): ##STR1## wherein R.sup.1, R.sup.2, and R.sup.3 are --COOR.sup.4, --COOR.sup.5, and --COOR.sup.6, respectively; R.sup.4, R.sup.5, and R.sup.6 each is hydrogen, lower alkyl, or alkali metal; W is hydroxyl; X, Y, and Z each is hydrogen or hydroxyl; a dotted line indicates the presence or absence of a single bond; or where W/R.sup.3, X/R.sup.1, and/or Z/R.sup.3 may be combined together, a lactone is formed, which compound is useful as a phospholipase A.sub.2 inhibitor. Process for the production of the compound (I) and a cell culture of a microorganism Circinotrichum falcatisporum RF-641 producing the same are also provided.
    Type: Grant
    Filed: June 27, 1990
    Date of Patent: March 24, 1992
    Assignee: Shionogi & Co., Ltd.
    Inventors: Tadashi Yoshida, Hiroshi Itazaki, Hitoshi Arita, Yoshimi Kawamura, Koichi Matsumoto
  • 1,4-benzodioxine and 1,4-benzodioxine derivatives and production thereof
    Patent number: 4595767
    Abstract: Highly safe new diuretics, i.e., 1,4-benzodioxane and 1,4-benzodioxine derivatives having potent antihypertensive activity but no or little uricesuric activity, which can be administered to human orally, intravenously, or hypodermically at a respective daily dosage of 0.1-2 mg/kg, 0.005-0.1 mg/kg, or 0.02-0.4 mg/kg.
    Type: Grant
    Filed: October 22, 1985
    Date of Patent: June 17, 1986
    Assignee: Shionogi & Co., Ltd.
    Inventors: Hiroshi Itazaki, Kunio Hayashi, Munenori Matsuura, Yukio Yonetani, Masuhisa Nakamura
  • Production of o-hydroxybenzyl alcohols
    Patent number: 4025553
    Abstract: A novel process for producing o-hydroxybenzyl alcohols useful as raw materials or intermediates in chemical or pharmaceutical industries, which comprises reacting phenols or naphthols with aromatic boronic acids and aldehydes in the presence of organic carboxylic acids, followed by degradation of the cyclic ester intermediates.
    Type: Grant
    Filed: September 23, 1975
    Date of Patent: May 24, 1977
    Assignee: Shionogi & Co., Ltd.
    Inventors: Wataru Nagata, Kyo Okada, Hiroshi Itazaki, Tsutomu Aoki