Patents by Inventor Tomohisa Takita

Tomohisa Takita 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: 6514946
    Abstract: 20,23-disubstituted mycaminosyltylonolide derivatives and use of the same in the field of the prophylaxis and treatment of pasteurellosis are disclosed. The di-substituents are peperidino optionally substituted with one or two methyl groups. The derivatives have selective antibacterial activity against Pasteurella.
    Type: Grant
    Filed: August 29, 2000
    Date of Patent: February 4, 2003
    Assignee: Zaidan Hojin Biseibutsu Kagaku Kenkyu Kai
    Inventors: Toshiaki Miyake, Tomohisa Takita, Masa Hamada, Tomio Takeuchi, Sumio Umezawa
  • Patent number: 4960910
    Abstract: The present invention relates to an oxetane derivative represented by the general formula (I): ##STR1## wherein R.sub.1 and R.sub.2 are each an acyl group and R.sub.3 is a hydrogen atom or a lower alkyl group, which is useful as an intermediate for the preparation of a compound having a (bishydroxymethyl)oxetane structure in its saccharide moiety, for example, oxetanosine, and a process for the preparation of the same.
    Type: Grant
    Filed: June 13, 1989
    Date of Patent: October 2, 1990
    Assignee: Nippon Kayaku Kabushiki Kaisha
    Inventors: Kuniki Kato, Tomohisa Takita, Shigeru Nishiyama, Shosuke Yamamura
  • Patent number: 4716221
    Abstract: This invention relates to a novel 4'-demethyl-4-epipodophylltoxin derivative of the formula: ##STR1## (wherein R.sub.1 is a lower alkyl group; X.sub.1 and X.sub.2 are each a hydroxyl group or an amino group substituted by one or two lower alkyls, provided that either one of X.sub.1 and X.sub.2 is an amino group substituted by one or two lower alkyls and the other is a hydroxyl group) and salts thereof.
    Type: Grant
    Filed: March 21, 1986
    Date of Patent: December 29, 1987
    Assignee: Zaidan Hojin Biseibutsu Kagaku Kenkyu Kai
    Inventors: Hamao Umezawa, Tomio Takeuchi, Shinichi Kondo, Wataru Tanaka, Tomohisa Takita, Yoshio Nishimura, Hiroshi Yoshikawa
  • Patent number: 4547567
    Abstract: This invention relates to novel 4'-demethyl-4-epipodophyllotoxin derivatives represented by the general formula (I), and salts thereof: ##STR1## wherein R is a lower alkyl group, and X.sub.1 and X.sub.2 are independently a hydroxyl group or an amino group, the one being an amino group and the other being a hydroxyl group. These novel derivatives have a high carcinostatic activity and a relatively high water solubility and hence are expected to be useful as carcinostatics.
    Type: Grant
    Filed: July 18, 1984
    Date of Patent: October 15, 1985
    Assignee: Zaidan Hojin Biseibutsu Kagaku Kenkyu Kai
    Inventors: Hamao Umezawa, Tomio Takeuchi, Shinichi Kondo, Wataru Tanaka, Tomohisa Takita, Yoshio Nishimura, Hiroshi Yoshikawa
  • Patent number: 4530998
    Abstract: This invention relates to 2'-deoxy-oxanosine represented by the following formula: ##STR1## and process for the preparation thereof. This new compound exhibits a growth inhibiting action to gram-negative bacteria and has a carcinostatic action.
    Type: Grant
    Filed: March 5, 1984
    Date of Patent: July 23, 1985
    Assignee: Zaidan Hojin Biseibutsu Kagaku KenkyuKai
    Inventors: Hamao Umezawa, Tomio Takeuchi, Masaaki Ishizuka, Tomohisa Takita, Nobuyoshi Shimada, Kuniki Kato
  • Patent number: 4495347
    Abstract: The novel antibiotic, oxanosine, having the structure ##STR1## inhibits the growth of Gram-negative bacteria and has antiviral activity. It is produced by cultivation of an oxanosine-producing microorganism of the genus Streptomyces, preferably Streptomyces capreolus MG265-CF3, ATCC No. 31963.
    Type: Grant
    Filed: November 5, 1982
    Date of Patent: January 22, 1985
    Assignee: Zaidan Hojin Biseibutsu Kagaku Kenkyu Kai
    Inventors: Hamao Umezawa, Nobuyoshi Shimada, Hiroshi Naganawa, Tomohisa Takita, Masa Hamada, Tomio Takeuchi
  • Patent number: 4394446
    Abstract: The novel antibiotic, oxanosine, having the structure ##STR1## inhibits the growth of Gram-negative bacteria and has antiviral and carcinostatic activity. It is produced by cultivation of an oxanosine-producing microorganism of the genus Streptomyces, preferably Streptomyces capreolus MG265-CF3, ATCC No. 31963.
    Type: Grant
    Filed: November 20, 1981
    Date of Patent: July 19, 1983
    Assignee: Zaidan Hojin Biseibutsu Kagaku Kenkyu Kai
    Inventors: Hamao Umezawa, Nobuyoshi Shimada, Hiroshi Naganawa, Tomohisa Takita, Masa Hamada, Tomio Takeuchi
  • Patent number: 4326054
    Abstract: Novel antibiotics cleomycins represented by the formula ##STR1## wherein R is a terminal amino residue of the cleomycin. These compounds are useful as a chemotherapeutic agent for treating cancer and bacterial infections.
    Type: Grant
    Filed: July 9, 1980
    Date of Patent: April 20, 1982
    Assignee: Zaidan Hojin Biseibutsu Kagaku Kenkyu Kai
    Inventors: Hamao Umezawa, Tomohisa Takita, Akio Fujii, Yasuhiko Muraoka, Mamoru Kunishima
  • Patent number: 4267102
    Abstract: N-methylbleomycins represented by the general formula ##STR1## which are useful as antitumor agents and bactericides; a method of preparing the same; and intermediate products in the preparation thereof.
    Type: Grant
    Filed: February 29, 1980
    Date of Patent: May 12, 1981
    Assignee: Nippon Kayaku Kabushiki Kaisha
    Inventors: Akio Fujii, Takeyo Fukuoka, Yasuhiko Muraoka, Tomohisa Takita, Hamao Umezawa
  • Patent number: 4240975
    Abstract: Bestatin, which is [(2S,3R)-3-amino-2-hydroxy-4-phenylbutanoyl]-L-leucine, and related compounds which inhibit aminopeptidase B, leucino aminopeptidase and Bleomycin hydrolase, enhance the anti-tumor effect of Bleomycin and exhibit an antifertility effect were synthesized and tested.
    Type: Grant
    Filed: September 26, 1979
    Date of Patent: December 23, 1980
    Assignee: Zaidan Hojin Biseibutsu Kagaku Kenkyu Kai
    Inventors: Hamao Umezawa, Takaaki Aoyagi, Tomohisa Takita, Rinzo Nishizawa, Tetsushi Saino
  • Patent number: 4238391
    Abstract: Novel 3-[(S)-1'-phenylethylamino]propylaminobleomycin obtained by reacting a reactive derivative of the carboxyl group of bleomycinic acid with N-[(S)-1'-phenylethyl]-1,3-diaminopropane, a non-toxic salt of said novel bleomycin, and a method for producing the novel bleomycin. Because of much reduction in the side effect causing pulmonary fibrosis, the novel bleomycin is more useful than a commercial bleomycin complex which gives rise to said undesirable side effect.
    Type: Grant
    Filed: July 18, 1979
    Date of Patent: December 9, 1980
    Assignee: Nippon Kayaku Kabushiki Kaisha
    Inventors: Tomohisa Takita, Akio Fujii, Takeyo Fukuoka, Yasuhiko Muraoka, Osamu Yoshioka, Hamao Umezawa
  • Patent number: 4195018
    Abstract: Novel 3-[(S)-1'-phenylethylamino]propylaminobleomycin obtained by reacting a reactive derivative of the carboxyl group of bleomycinic acid with N-[(S)-1'-phenylethyl]-1,3-diaminopropane, a non-toxic salt of said novel bleomycin, and a method for producing the novel bleomycin. Because of much reduction in the side effect causing pulmonary fibrosis, the novel bleomycin is more useful than a commercial bleomycin complex which gives rise to said undesirable side effect.
    Type: Grant
    Filed: June 15, 1978
    Date of Patent: March 25, 1980
    Assignee: Nippon Kayaku Kabushiki Kaisha
    Inventors: Tomohisa Takita, Akio Fujii, Takeyo Fukuoka, Yasuhiko Muraoka, Osamu Yoshioka, Hamao Umezawa
  • Patent number: 4189604
    Abstract: Bestatin, which is [(2S,3R)-3-amino-2-hydroxy-4-phenylbutanoyl]-L-leucine, and related compounds which inhibit aminopeptidase B, leucino aminopeptidase and Bleomycin hydrolase, enhance the anti-tumor effect of Bleomycin and exhibit an antifertility effect were synthesized and tested.
    Type: Grant
    Filed: June 24, 1977
    Date of Patent: February 19, 1980
    Assignee: Zaidan Hojin Biseibutsu Kagaku Kenkyu Kai
    Inventors: Hamao Umezawa, Takaaki Aoyagi, Tomohisa Takita, Rinzo Nishizawa, Tetsushi Saino
  • Patent number: 3984390
    Abstract: By adding a specific amine in culturing under aerobic conditions actinomycetales capable of producing phleomycin group antibiotics, which have been inoculated into a nutrient medium to produce antitumor phleomycin group antibiotics, it is possible to obtain specific phleomycin group antibiotics having a side chain structure corresponding to said amine. The phleomycin group antibiotics thus produced are collected from the culture medium in a conventional way.
    Type: Grant
    Filed: March 2, 1973
    Date of Patent: October 5, 1976
    Assignee: Zaidan Hojin Biseibutsu Kagaku Kenkyu Kai
    Inventors: Hamao Umezawa, Akio Fujii, Tomohisa Takita, Nobuyoshi Shimada
  • Patent number: 3960834
    Abstract: By thermal decomposition of 3-(S,S-dimethylmercapto)propylaminobleomycin, there is easily obtained 3-(methylmercapto)propylaminobleomycin which is a useful antibiotic substance having an extremely high antimicrobial activity and a carcinostartic activity with low toxicity.
    Type: Grant
    Filed: November 2, 1973
    Date of Patent: June 1, 1976
    Assignee: Zaidan Hojin Biseibutsu Kagaku Kenkyu Kai
    Inventors: Hamao Umezawa, Tomohisa Takita, Akio Fujii, Hiroko Ito
  • Patent number: 3953594
    Abstract: This invention is concerned with the oxidative conversion of an unstable phleomycin group to a stable bleomycin group antibiotic having the partial structure: ##SPC1##By treatment with potassium ferricyanide or manganese dioxide.
    Type: Grant
    Filed: August 7, 1973
    Date of Patent: April 27, 1976
    Assignee: Zaidan Hojin Biseibutsu Kagaku Kenkyu Kai
    Inventors: Hamao Umezawa, Tomohisa Takita, Yasuhiko Muraoka, Akio Fujii
  • Patent number: RE30451
    Abstract: A novel process for producing antibiotics bleomycins by innoculating and aerobically culturing in a nutrient source-containing medium a bleomycin-producing strain belonging to the actinomyces, wherein the culture is effected in the presence of an amino compound having at least one ##STR1## group and at least one basic group selected from amino, imino, guanidino, amidino and sulfonium groups and nitrogen-containing cyclic compounds, or in the presence of a compound convertible in the culture liquor to such amino compound as mentioned above, thereby selectively producing a known or novel bleomycin component corresponding to the said amino compound or to an amino compound derived from the above-mentioned compound, and then the known or novel bleomycin is recovered by known means from the culture medium.
    Type: Grant
    Filed: May 24, 1979
    Date of Patent: December 16, 1980
    Assignee: Zaidan Jojin Biseibutsu Kagaku Kenkyu Kai
    Inventors: Hamao Umezawa, Kenji Maeda, Tomohisa Takita, Yuya Nakayama, Akio Fujii, Nobuyoshi Shimada, Hideo Chimura