Patents by Inventor Isamu Saikawa

Isamu Saikawa 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).

  • Patent number: 5144027
    Abstract: Novel cephalosporins which has attached to the exomethylene group at the 3-position of the cephem ring a substituted or unsubstituted aryl, acylamino, aromatic heterocyclic, triazolyl or tetrazolyl group, said aromatic heterocyclic group being attached through a carbon-carbon bond and said triazolyl or tetrazolyl group being attached through a carbon-nitrogen bond, and has the following group attached to the amino group at the 7-position: ##STR1## wherein A represents a group of the formula, --CH.sub.2 -- or a group of the formula ##STR2## in which R.sup.5 represents a hydrogen atom or an alkyl group, and the bond.about.represents syn or anti isomer or their mixture; R.sup.3 represents a hydrogen or halogen atom; and R.sup.4 represents a hydrogen atom or an amino group which may be protected or substituted. These cephalosporins have a broad antibacterial spectrum, are stable against .beta.-lactamase produced by bacteria, have a low toxicity, and are well absorbed when administered orally or parenterally.
    Type: Grant
    Filed: May 24, 1991
    Date of Patent: September 1, 1992
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Hiroshi Sadaki, Hirokazu Narita, Hiroyuki Imaizumi, Yoshinori Konishi, Takihiro Inaba, Tatsuo Hirakawa, Hideo Taki, Masaru Tai, Yasuo Watanabe, Isamu Saikawa
  • Patent number: 5011973
    Abstract: The process for producing bischoline-disulfonate derivatives of Formula (I) ##STR1## useful for enhancing the digestive function comprising reacting, in the presence of an organic solvent, a trimethylammonium salt derivative of Formula (II) ##STR2## wherein R.sup.1 and R.sup.2 are individually lower alkyl and X is a group removable by a disulfonic acid of Formula (III)R(SO.sub.3 H).sub.2 (III)wherein R is a naphthylene, or an organic base salt of said acid.
    Type: Grant
    Filed: May 15, 1989
    Date of Patent: April 30, 1991
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Yasuyuki Suzuki, Noboru Takagawa, Mikio Kawabata, Mariko Hayashi, Akiko Takagi, Takako Wakamiya, Isamu Saikawa
  • Patent number: 4990508
    Abstract: This invention relates to a novel pyridone carboxylic acid derivative having a substituted or unsubstituted cyclopropyl group at the 10-position of pyridobenzoxazine, pyridobenzothiazine or pyridoquinoxaline and a salt thereof, a process for the production thereof and an antibacterial agent comprising the same.
    Type: Grant
    Filed: April 13, 1989
    Date of Patent: February 5, 1991
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Hirokazu Narita, Yozo Todo, Jun Nitta, Hiroyasu Takagi, Fumihiko Iino, Mikako Miyajima, Yoshikazu Fukuoka, Isamu Saikawa
  • Patent number: 4879381
    Abstract: Novel cephalosporins which has attached to the exomethylene group at the 3-position of the cephem ring a substituted or unsubstituted aryl, acylamino, aromatic heterocyclic, triazolyl or tetrazolyl group, said aromatic heterocyclic group being attached through a carbon-carbon bond and said triazolyl or tetrazolyl group being attached through a carbon-nitrogen bond, and has the following group attached to the amino group at the 7-position: ##STR1## wherein A represents a group of the formula, --CH.sub.2 -- or a group of the formula ##STR2## in which R.sup.5 represents a hydrogen atom or an alkyl group, and the bond represents syn or anti isomer or their mixture; R.sup.3 represents a hydrogen or halogen atom; and R.sup.4 represents a hydrogen atom or an amino group which may be protected or substituted. These cephalosporins have a broad antibacterial spectrum, are stable against .beta.-lactamase produced by bacteria, have a low toxicity, and are well absorbed when administered orally or parenterally.
    Type: Grant
    Filed: March 6, 1987
    Date of Patent: November 7, 1989
    Assignee: Toyoma Chemical Company, Ltd.
    Inventors: Hiroshi Sadaki, Narita Hirokazu, Hiroyuki Imaizumi, Yoshinori Konishi, Takihiro Inaba, Tatsuo Hirakawa, Hideo Taki, Masaru Tai, Yasuo Watanabe, Isamu Saikawa
  • Patent number: 4851535
    Abstract: This invention relates to a process for industrially producing a 1-substituted aryl-1,4-dihydro-4-oxonaphthyridine derivative and a salt thereof which are useful as an antibacterial agent, and also to intermediates therefor and processes for producing the intermediates.
    Type: Grant
    Filed: June 29, 1987
    Date of Patent: July 25, 1989
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Yozo Todo, Tetsuo Yamafuji, Katsuyuki Nagumo, Isao Kitayama, Hideyoshi Nagaki, Mikako Miyajima, Yoshinori Konishi, Hirokazu Narita, Shuntaro Takano, Isamu Saikawa
  • Patent number: 4744985
    Abstract: Novel substances having carcinostatic and immunostimulating activity, which are obtained from a culture or its supernatant fluid prepared by culturing bacteria belonging to Fusobacterium genus. Said substances are useful for the treatment of cancerous diseases lower warm-blooded animals. This disclosure concerns such substances and a process for preparing the same and a carcinostatic agent containing the same.
    Type: Grant
    Filed: August 21, 1980
    Date of Patent: May 17, 1988
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Kenzo Tamai, Isamu Saikawa, Takashi Yasuda, Shohachi Murakami, Toyoo Maeda, Hisatsugu Tsuda, Hiroshi Sakai, Masatoshi Sugita, Yoshiko Yamamoto, Hisashi Minami, Takako Hori
  • 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
  • Patent number: 4717767
    Abstract: This invention relates to a 7-amino-3-(pyrazinylmethyl)- or (pyridazinylmethyl)-cephalosporins of the formula: ##STR1## wherein R.sup.1 represents a hydrogen atom or a carboxyl-protecting group; R.sup.2 represents a group of the formula: ##STR2## in which R.sup.6 represents a hydrogen atom, a C.sub.1-5 alkyl group or a di-C.sub.1-5 alkylamino group; R.sup.13 represents a C.sub.1-5 alkyl group; and R.sup.28 represents an amino group.
    Type: Grant
    Filed: July 22, 1986
    Date of Patent: January 5, 1988
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Hiroshi Sadaki, Hiroyuki Imaizumi, Takashi Nagai, Kenji Takeda, Isao Myokan, Takihiro Inaba, Yasuo Watanabe, Yoshikazu Fukuoka, Shinzaburo Minami, Isamu Saikawa
  • Patent number: 4704459
    Abstract: This invention relates to a process for industrially producing a 1-substituted aryl-1,4-dihydro-4-oxonaphthyridine derivative and a salt thereof which are useful as an antibacterial agent, and also to intermediates therefor and processes for producing the intermediates.
    Type: Grant
    Filed: January 17, 1986
    Date of Patent: November 3, 1987
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Yozo Todo, Tetsuo Yamafuji, Katsuyuki Nagumo, Isao Kitayama, Hideyoshi Nagaki, Mikako Miyajima, Yoshinori Konishi, Hirokazu Narita, Shuntaro Takano, Isamu Saikawa
  • Patent number: 4698352
    Abstract: This invention relates to a novel 4-oxo-1,4-dihydronicotinic acid derivative ##STR1## or a salt thereof, wherein R.sup.1 is hydrogen or carboxyl-protecting group;R.sup.2 is substituted phenyl and naphthyl, or a substituted or unsubstituted heterocyclic group; andR.sup.3 is haloalkyl, aminoalkyl, or substituted or unsubstituted alkenyl, phenylalkenyl, naphthylalkenyl, phenylalkyl, naphthylalkyl, phenylalkynyl, naphthylalkynyl, heterocyclic alkyl, heterocyclic alkenyl, phenyl, naphthyl, cycloalkyl, cycloalkenyl, carboxylic acyl, iminoalkyl, heterocyclic or bridged hydrocarbon, which has a broad antibacterial spectrum and a low toxicity, and are useful for treatment of diseases of human beings and animals, to a process for producing the same and to an antibacterial agent containing the same.
    Type: Grant
    Filed: October 27, 1983
    Date of Patent: October 6, 1987
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Hirokazu Narita, Yoshinori Konishi, Jun Nitta, Shunjiro Misumi, Hideyoshi Nagaki, Isao Kitayama, Yoriko Nagai, Yasuo Watanabe, Nobuyuki Matsubara, Shinzaburo Minami, Isamu Saikawa
  • Patent number: 4673738
    Abstract: This invention relates to novel 7-(substituted or unsubstituted amino)-3-substituted methyl-.DELTA..sup.3 -cephem-4-carboxylic acids in which a substituted or unsubstituted 1,2,4-triazolyl or 2-(1,2,3,4-tetrazolyl) group attaches to the exomethylene group at the 3-position of the cephem ring through a carbon-nitrogen bond. These cephalosporins are useful intermediates for producing various novel cephalosporins. Also, this invention concerns a process for producing a compound represented by the formula: ##STR1## which comprises reacting a compound represented by the formula: ##STR2## with an optionally substituted triazole or tetrazole in the presence of an acid or a complex of the acid in an organic solvent at 0.degree. to 80.degree. C.
    Type: Grant
    Filed: September 26, 1984
    Date of Patent: June 16, 1987
    Assignee: Handi-Pac Inc.
    Inventors: Hiroshi Sadaki, Hirokazu Narita, Hiroyuki Imaizumi, Yoshinori Konishi, Takihiro Inaba, Tatsuo Hirakawa, Hideo Taki, Masaru Tai, Yasuo Watanabe, Isamu Saikawa
  • 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
  • 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
  • Patent number: 4618606
    Abstract: The invention relates to antibiotic compounds of the formula: ##STR1## wherein R.sup.1 represents a hydrogen atom or a carboxyl-protecting group; R.sup.2 represents a group of the formula: ##STR2## R.sup.3 represents a hydrogen atom or an alkoxy group; R.sup.4 represents a hydrogen atom or a halogen atom; R.sup.5 represents a hydrogen atom or a protected or unprotected amino group; A represents a group of the formula, --CH.sub.2 -- or a group of the formula, ##STR3## or a group of the formula, ##STR4## and the bond means that the compound may be a synisomer or an anti-isomer or a mixture thereof.
    Type: Grant
    Filed: November 16, 1983
    Date of Patent: October 21, 1986
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Hiroshi Sadaki, Hiroyuki Imaizumi, Takashi Nagai, Kenji Takeda, Isao Myokan, Takihiro Inaba, Yasuo Watanabe, Yoshikazu Fukuoka, Shinzaburo Minami, Isamu Saikawa
  • Patent number: 4614819
    Abstract: This invention relates to a novel process for producing a useful cephalosporin which comprises reacting a thiolo ester compound with a 7-aminocephalosporin in the presence of boron trifluoride or a complex compound thereof. This process enables the cephalosporin to be produced with a high purity in a high yield.
    Type: Grant
    Filed: September 19, 1984
    Date of Patent: September 30, 1986
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Takashi Nagai, Hirokazu Ochiai, Takihiro Inaba, Isao Myokan, Hiroshi Sadaki, Isamu Saikawa
  • Patent number: 4591558
    Abstract: Novel TF-2 substances having antitumor and immunostimulating activity, which are obtained from a culture or its supernatant fluid prepared by culturing bacteria belonging to Fusobacterium genus. Said substances are useful for the treatment of cancerous diseases of the mammals including human beings. This disclosure concerns such substances and a process for preparing the same and an antitumor agent containing the same.
    Type: Grant
    Filed: August 6, 1984
    Date of Patent: May 27, 1986
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Kenzo Tamai, Isamu Saikawa, Takashi Yasuda, Shohachi Murakami, Toyoo Maeda, Hisatsugu Tsuda, Hiroshi Sakai, Masatoshi Sugita, Yoshiko Yamamoto, Hisashi Minami, Takako Hori
  • 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
  • Patent number: 4547462
    Abstract: This invention relates to a process for producing a TF-500 substance having carcinostatic and immunostimulating activities, which comprises subjecting organisms belonging to the Fusobacterium genus to extraction treatment with a dialkyl sulfoxide and obtaining said TF-500 substance from the resulting extract.
    Type: Grant
    Filed: August 16, 1983
    Date of Patent: October 15, 1985
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Kenzo Tamai, Isamu Saikawa, Takashi Yasuda, Shohachi Murakami, Toyoo Maeda, Hisatsugu Tsuda, Hiroshi Sakai, Masatoshi Sugita, Yoshiko Yamamoto, Hisashi Minami, Takako Hori
  • Patent number: 4489072
    Abstract: Novel cephalosporins which has attached to the exomethylene group at the 3-position of the cephem ring a substituted or unsubstituted aryl, acylamino, aromatic heterocyclic, triazolyl or tetrazolyl group, said aromatic heterocyclic group being attached through a carbon-carbon bond and said triazolyl or tetrazolyl group being attached through a carbon-nitrogen bond, and has the following group attached to the amino group at the 7-position: ##STR1## wherein A represents a group of the formula, --CH.sub.2 -- or a group of the formula ##STR2## in which R.sup.5 represents a hydrogen atom or an alkyl group, and the bond represents syn or anti isomer or their mixture; R.sup.3 represents a hydrogen or halogen atom; and R.sup.4 represents a hydrogen atom or an amino group which may be protected or substituted. These cephalosporins have a broad antibacterial spectrum, are stable against .beta.-lactamase produced by bacteria, have a low toxicity, and are well absorbed when administered orally or parenterally.
    Type: Grant
    Filed: September 23, 1981
    Date of Patent: December 18, 1984
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Hiroshi Sadaki, Hirokazu Narita, Hiroyuki Imaizumi, Yoshinori Konishi, Takihiro Inaba, Tatsuo Hirakawa, Hideo Taki, Masaru Tai, Yasuo Watanabe, Isamu Saikawa
  • Patent number: 4477437
    Abstract: Novel TF-2 substances having carcinostatic and immunostimulating activity, which are obtained from a culture or its supernatant fluid prepared by culturing bacteria belonging to Fusobacterium genus. Said substances are useful for the treatment of cancerous diseases of the mammals including human being. This disclosure concerns such substances and a process for preparing the same and a carcinostatic agent containing the same.
    Type: Grant
    Filed: February 11, 1982
    Date of Patent: October 16, 1984
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Kenzo Tamai, Isamu Saikawa, Takashi Yasuda, Shohachi Murakami, Toyoo Maeda, Hisatsugu Tsuda, Hiroshi Sakai, Masatoshi Sugita, Yoshiko Yamamoto, Hisashi Minami, Takako Hori