Patents by Inventor Masaru Tai

Masaru Tai 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: 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: 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: 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: 4428936
    Abstract: An antibacterial composition for medical use comprising a cephalosporin or a pharmaceutically acceptable salt thereof and a .beta.-lactamase-inhibiting compound having a .beta.-lactam ring. The composition exhibits synergistic effect which is much greater than the sum of antibacterial effects of each component used alone.
    Type: Grant
    Filed: September 16, 1980
    Date of Patent: January 31, 1984
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Isamu Saikawa, Takashi Yasuda, Masaru Tai, Yutaka Takashita, Hiroshi Sakai, Michiko Mae, Masahiro Takahata, Susumu Mitsuhashi
  • Patent number: 4395412
    Abstract: A 7.alpha.-methoxycephalosporin represented by the general formula: ##STR1## wherein R.sup.1 represents a hydrogen atom or a carboxyl-protecting group; R.sup.2 represents an organic group linked to the carbon atom through an oxygen or sulfur atom; R.sup.3 represents a lower alkyl group; n is 0, 1 or 2; A represents a hydrogen atom or a substituted or unsubstituted alkyl group; and B represents a substituted or unsubstituted alkyl, cycloalkyl, cycloalkenyl, cycloalkadienyl or heterocyclic group, and a salt thereof. These compounds have a broad antibacterial spectrum, high resistance to .beta.-lactamase produced from bacteria, and an effective antibacterial activity against clinical isolates of bacteria.
    Type: Grant
    Filed: December 31, 1980
    Date of Patent: July 26, 1983
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Isamu Saikawa, Shuntaro Takano, Hiroyuki Imaizumi, Isamu Takakura, Hirokazu Ochiai, Takashi Yasuda, Hideo Taki, Masaru Tai, Yutaka Kodama
  • Patent number: 4324783
    Abstract: An antibacterial composition for medical use comprising 6-[D(-)-.alpha.-(4-ethyl-2,3-dioxo-1-piperazinylcarbonylamino)phenylacetam ido]penicillanic acid or a pharmaceutically acceptable salt thereof and a .beta.-lactamase-inhibiting penicillin or cephalosporin. The composition exhibits synergistic effect which is much greater than the sum of antibacterial effects of each component used alone.
    Type: Grant
    Filed: January 17, 1980
    Date of Patent: April 13, 1982
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Isamu Saikawa, Takashi Yasuda, Masaru Tai, Yutaka Takashita, Hiroshi Sakai, Michiko Mae, Masahiro Takahata, Susumu Mitsuhashi
  • Patent number: 4321265
    Abstract: A 7.alpha.-methoxycephalosporin represented by the general formula: ##STR1## wherein R.sup.1 represents a hydrogen atom or a carboxyl-protecting group; R.sup.2 represents an organic group linked to the carbon atom through an oxygen or sulfur atom; R.sup.3 represents a lower alkyl group; n is 0, 1 or 2; A represents a hydrogen atom or a substituted or unsubstituted alkyl group; and B represents a substituted or unsubstituted alkyl, cycloalkyl, cycloalkenyl, cycloalkadienyl or heterocyclic group, and a salt thereof. These compounds have a broad antibacterial spectrum, high resistance to .beta.-lactamase produced from bacteria, and an effective antibacterial activity against clinical isolates of bacteria.
    Type: Grant
    Filed: February 1, 1980
    Date of Patent: March 23, 1982
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Isamu Saikawa, Shuntaro Takano, Hiroyuki Imaizumi, Isamu Takakura, Hirokazu Ochiai, Takashi Yasuda, Hideo Taki, Masaru Tai, Yutaka Kodama
  • Patent number: 4263292
    Abstract: A 7.alpha.-methoxycephalosporin represented by the general formula and a salt thereof: ##STR1## wherein R.sup.1 represents a hydrogen atom or a carboxyl-protecting group; R.sup.2 represents an organic group linked to the carbon atoms through an oxygen or sulfur atom; R.sup.3 represents a lower alkyl group; n is 0, 1 or 2; A represents a hydrogen atom or a substituted or unsubstituted alkyl group; and B represents a substituted or unsubstituted alkyl group. These compounds have a broad antibacterial spectrum and high resistance to .beta.-lactamase produced from bacteria, and are well absorbed in a living body.
    Type: Grant
    Filed: October 4, 1979
    Date of Patent: April 21, 1981
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Isamu Saikawa, Shuntaro Takano, Hiroyuki Imaizumi, Isamu Takakura, Hirokazu Ochiai, Takashi Yasuda, Hideo Taki, Masaru Tai, Yutaka Kodama
  • Patent number: 4199566
    Abstract: An antibacterial composition for medical use comprising 6-[-)-.alpha.-(4-ethyl-2,3-dioxo-1-piperazinylcarbonylamino)phenylacetamid o]penicillanic acid or a pharmaceutically acceptable salt thereof and a .beta.-lactamase-inhibiting penicillin or cephalosporin. The composition exhibits synergistic effect which is much greater than the sum of antibacterial effects of each component used alone.
    Type: Grant
    Filed: June 6, 1978
    Date of Patent: April 22, 1980
    Assignee: Toyama Chemical Company, Limited
    Inventors: Isamu Saikawa, Takashi Yasuda, Masaru Tai, Yutaka Takashita, Hiroshi Sakai, Michiko Mae, Masahiro Takahata, Susumu Mitsuhashi
  • Patent number: 4129730
    Abstract: Novel 7.alpha.-methoxy-cephalosporins and non-toxic salts thereof, which contain a di-oxo-piperazinylcarbonylamino group in molecule. These compounds are valuable antibacterial compounds for use in mammals including man. This disclosure relates to such compounds.
    Type: Grant
    Filed: January 13, 1977
    Date of Patent: December 12, 1978
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Isamu Saikawa, Shuntaro Takano, Hiroyuki Imaizumi, Isamu Takakura, Hirokazu Ochiai, Takashi Yasuda, Hideo Taki, Masaru Tai, Yutaka Kodama
  • Patent number: 3972141
    Abstract: There is disclosed a telephone number indexing device which comprises a casing having an upper opening and housing therein a plurality of cards on which telephone numbers are recorded. When any card is pulled upwards from the casing through the upper opening thereof for learning a required telephone number, the card is held in place in a manner that card guide and stopper means on the inner wall of casing or resilient members 4 provided in the casing are utilized for retaining a stopper 15 provided in the lower portion of each card.
    Type: Grant
    Filed: July 25, 1975
    Date of Patent: August 3, 1976
    Inventor: Masaru Tai