Patents by Inventor Ryuko Takeno

Ryuko Takeno 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).

  • 4H-1-benzopyran-4-one derivative or its salt, process for producing the same and pharmaceutical composition comprising the same as active ingredient
    Patent number: 4954518
    Abstract: This invention relates to a 4H-1-benzopyran-4-one derivative represented by the formula: ##STR1## or a salt thereof, a process for producing the same and a pharmaceutical composition comprising the same as active ingredient.
    Type: Grant
    Filed: October 7, 1988
    Date of Patent: September 4, 1990
    Assignee: Toyama Chemical Company, Ltd.
    Inventors: Shuntaro Takano, Chosaku Yoshida, Takihiro Inaba, Keiichi Tanaka, Ryuko Takeno, Hideyoshi Nagaki, Tomoya Shimotori, Shinji Makino
  • Novel process for producing a cephalosporin
    Patent number: 4736026
    Abstract: The invention relates to a process for producing a cephalosporin of the formula ##STR1## by reacting the compound ##STR2## with the compound ##STR3## in the presence of boron trifluoride or a complex thereof.
    Type: Grant
    Filed: June 24, 1986
    Date of Patent: April 5, 1988
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Hiroyuki Imaizumi, Takihiro Inaba, Seishi Morita, Ryuko Takeno, Yoshiharu Murotani, Hirohiko Fukuda, Junichi Yoshida, Kiyoshi Tanaka, Shuntaro Takano, Isamu Saikawa
  • Novel process for producing 2-(2-aminothiazol-4-yl)glyoxylic acid derivative or a salt thereof, and intermediates therefor and process for producing the intermediates
    Patent number: 4667040
    Abstract: This invention relates to a novel process for producing a 2-(2-aminothiazol-4-yl)glyoxylic acid derivative or a salt thereof which are useful in producing a cephalosporin antibiotic, and to intermediates for said derivative and salt and a process for producing the intermediates.
    Type: Grant
    Filed: July 9, 1985
    Date of Patent: May 19, 1987
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Hiroshi Sadaki, Hiroyuki Imaizumi, Kenji Takeda, Takihiro Inaba, Ryuko Takeno, Seishi Morita, Tetsuya Kajita, Isamu Saikawa
  • Aminothiazole intermediate for a cephalosporin
    Patent number: 4656287
    Abstract: This invention relates to a novel aminothiazole intermediate for production of a cephalosporin of antibiotic activity.
    Type: Grant
    Filed: July 11, 1985
    Date of Patent: April 7, 1987
    Assignee: Toyoma Chemical Co., Ltd.
    Inventors: Hiroyuki Imaizumi, Takihiro Inaba, Seishi Morita, Ryuko Takeno, Yoshiharu Murotani, Hirohiko Fukuda, Junichi Yoshida, Kiyoshi Tanaka, Shuntaro Takano, Isamu Saikawa
  • Process for producing 2-(2-aminothiazol-4-yl)glyoxylic acid derivative or a salt thereof, and intermediates therefor and process for producing the intermediates
    Patent number: 4563534
    Abstract: This invention relates to a novel process for producing a 2-(2-aminothiazol-4-yl)glyoxylic acid derivative or a salt thereof which are useful in producing a cephalosporin antibiotic, and to intermediates for said derivative and salt and a process for producing the intermediates.
    Type: Grant
    Filed: June 14, 1983
    Date of Patent: January 7, 1986
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Hiroshi Sadaki, Hiroyuki Imaizumi, Kenji Takeda, Takihiro Inaba, Ryuko Takeno, Seishi Morita, Tetsuya Kajita, Isamu Saikawa
  • 1-(4-Aminobenzyl)-2,3-dioxopiperazine derivatives, acid addition salts thereof and process for producing same
    Patent number: 4477666
    Abstract: A 1-(4-aminobenzyl)-2,3-dioxopiperazine derivative represented by the formula: ##STR1## and an acid addition salt thereof have excellent carcinostatic activity but a low toxicity. Therefore, said compounds are useful as medicines and also as intermediates.
    Type: Grant
    Filed: February 12, 1982
    Date of Patent: October 16, 1984
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Takako Hori, Chosaku Yoshida, Yasuo Kiba, Ryuko Takeno, Joji Nakano, Jun Nitta, Sumiko Kishimoto, Shohachi Murakami, Hisatsugu Tsuda, Isamu Saikawa
  • Novel 1-(4-piperidiniobenzyl)-2,3-dioxopiperazine derivatives or acid addition salts thereof
    Patent number: 4477664
    Abstract: A 1-(4-aminobenzyl)-2,3-dioxopiperazine derivative represented by the formula: ##STR1## and an acid addition salt thereof have excellent carcinostatic activity but a low toxicity. Therefore, said compounds are useful as medicines and also as intermediates.
    Type: Grant
    Filed: February 22, 1982
    Date of Patent: October 16, 1984
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Takako Hori, Chosaku Yoshida, Yasuo Kiba, Ryuko Takeno, Joji Nakano, Jun Nitta, Sumiko Kishimoto, Shohachi Murakami, Hisatsugu Tsuda, Isamu Saikawa
  • 1-(4-Aminobenzyl)-2,3-dioxopiperazine derivatives, acid addition salts thereof and process for producing same
    Patent number: 4460774
    Abstract: A 1-(4-aminobenzyl)-2,3-dioxopiperazine derivative represented by the formula: ##STR1## and an acid addition salt thereof have excellent carcinostatic activity but a low toxicity. Therefore, said compounds are useful as medicines and also as intermediates.
    Type: Grant
    Filed: February 12, 1982
    Date of Patent: July 17, 1984
    Assignee: Toyama Chemical Company, Limited
    Inventors: Takako Hori, Chosaku Yoshida, Yasuo Kiba, Ryuko Takeno, Joji Nakano, Jun Nitta, Sumiko Kishimoto, Shohachi Murakami, Hisatsugu Tsuda, Isamu Saikawa
  • 1-(4-Aminobenzyl)-2,3-dioxopiperazine derivatives and salts thereof
    Patent number: 4459407
    Abstract: A 1-(4-aminobenzyl)-2,3-dioxopiperazine derivative represented by the formula: ##STR1## and a salt thereof have excellent carcinostatic activity but a low toxicity. Therefore, said compounds are useful as medicines and also as intermediates.
    Type: Grant
    Filed: February 2, 1982
    Date of Patent: July 10, 1984
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Takako Hori, Chosaku Yoshida, Yasuo Kiba, Ryuko Takeno, Joji Nakano, Jun Nitta, Sumiko Kishimoto, Shohachi Murakami, Hisatsugu Tsuda, Isamu Saikawa
  • 4-[4-(Thiazolyl-amino)benzyl]-2,3-dioxopiperazine derivatives, acid addition salts thereof and process for producing same
    Patent number: 4448963
    Abstract: A 1-(4-aminobenzyl)-2,3-dioxopiperazine derivative represented by the formula: ##STR1## and an acid addition salt thereof have excellent carcinostatic activity but a low toxicity. Therefore, said compounds are useful as medicines and also as intermediates.
    Type: Grant
    Filed: February 22, 1982
    Date of Patent: May 15, 1984
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Takako Hori, Chosaku Yoshida, Yasuo Kiba, Ryuko Takeno, Joji Nakano, Jun Nitta, Sumiko Kishimoto, Shohachi Murakami, Hisatsugu Tsuda, Isamu Saikawa
  • 1-(4-Aminobenzyl)-2,3-dioxopiperazine derivatives, acid addition salts thereof and process for producing same
    Patent number: 4436921
    Abstract: A 1-(4-aminobenzyl)-2,3-dioxopiperazine derivative represented by the formula: ##STR1## and an acid addition salt thereof have excellent carcinostatic activity but a low toxicity. Therefore, said compounds are useful as medicines and also as intermediates.
    Type: Grant
    Filed: July 16, 1980
    Date of Patent: March 13, 1984
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Takako Hori, Chosaku Yoshida, Yasuo Kiba, Ryuko Takeno, Joji Nakano, Jun Nitta, Sumiko Kishimoto, Shohachi Murakami, Hisatsugu Tsuda, Isamu Saikawa