Patents by Inventor Tetsuo Yamafuji

Tetsuo Yamafuji 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).

  • 2,3-diketopiperazine derivatives or their salts
    Patent number: 6153613
    Abstract: The present invention relates to a 2,3-diketopiperazine derivative or a salt thereof, which has inhibitory effect on platelet aggregation because of glycoprotein IIb/IIIa receptor antagonism and hence is useful as a prophylactic and therapeutic agent for diseases associated with platelet aggregation.General formula ##STR1## wherein R.sup.1 represents a protected or unprotected amidino group; R.sup.2 represents a hydrogen atom or a carboxyl-protecting group; A represents a substituted or unsubstituted lower alkylene group; B represents --O--, --CONH--, --NHCO-- or --SO.sub.2 NH--; Y represents a substituted or unsubstituted lower alkylene group; and the broken line represents a single bond or a double bond.
    Type: Grant
    Filed: October 29, 1998
    Date of Patent: November 28, 2000
    Assignee: Toyoma Chemical Co., Ltd.
    Inventors: Satoshi Ono, Tetsuo Yamafuji, Hirohiko Yamamoto, Hiroyuki Egawa, Yousuke Furuta, Hidetoshi Kaga
  • 2,3-diketopiperazine derivatives or their salts
    Patent number: 5877174
    Abstract: The present invention relates to a 2,3-diketopiperazine derivative or a salt thereof, which has inhibitory effect on platelet aggregation because of glycoprotein IIb/IIIa receptor antagonism and hence is useful as a prophylactic and therapeutic agent for diseases associated with platelet aggregation. General formula: ##STR1## wherein R.sup.1 represents a protected or unprotected amidino group; R.sup.2 represents a hydrogen atom or a carboxyl-protecting group; A represents a substituted or unsubstituted lower alkylene group; B represents --O--, --CONH--, --NHCO--or --SO.sub.2 NH--; Y represents a substituted or unsubstituted lower alkylene group; and the broken line represents a single bond or a double bond.
    Type: Grant
    Filed: May 30, 1997
    Date of Patent: March 2, 1999
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Satoshi Ono, Tetsuo Yamafuji, Hirohiko Yamamoto, Hiroyuki Egawa, Yousuke Furuta, Hidetoshi Kaga
  • 1,2-ethanediol derivative and salt thereof, process for producing the same, and cerebral function-improving agent comprising the same
    Patent number: 5872117
    Abstract: This invention relates to a 1,2-ethanediol derivative and a salt thereof, a process for producing the same, and a cerebral function-improving agent comprising the same. The cerebral function-improving agent of this invention is useful for treating cerebrovascular dementia, senile dementia, Alzheimer's dementia, sequelae of ischemic encephalopathy and cerebral apoplexy.
    Type: Grant
    Filed: November 4, 1997
    Date of Patent: February 16, 1999
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Satoshi Ono, Tetsuo Yamafuji, Hisaaki Chaki, Mutsuko Maekawa, Yozo Todo, Hirokazu Narita
  • 1,2-ethanediol derivative and salt thereof, process for producing the same, and cerebral function-improving agent comprising the same
    Patent number: 5719150
    Abstract: This invention relates to a 1,2-ethanediol derivative and a salt thereof, a process for producing the same, and a cerebral function-improving agent comprising the same. The cerebral function-improving agent of this invention is useful for treating cerebrovascular dementia, senile dementia, Alzheimer's dementia, sequelae of ischemic encephalopathy and cerebral apoplexy.
    Type: Grant
    Filed: November 14, 1996
    Date of Patent: February 17, 1998
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Satoshi Ono, Tetsuo Yamafuji, Hisaaki Chaki, Mutsuko Maekawa, Yozo Todo, Hirokazu Narita
  • 1,2-ethanediol derivative and salt thereof and cerebral function-improving agent comprising the same
    Patent number: 5658904
    Abstract: This invention relates to a 1,2-ethanediol derivative and a salt thereof, a process for producing the same, and a cerebral function-improving agent comprising the same. The cerebral function-improving agent of this invention is useful for treating cerebrovascular dementia, senile dementia, Alzheimer's dementia, sequelae of ischemic encephalopathy and cerebral apoplexy.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: August 19, 1997
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Satoshi Ono, Tetsuo Yamafuji, Hisaaki Chaki, Mutsuko Maekawa, Yozo Todo, Hirokazu Narita
  • 1,2-ethanediol derivative and salt thereof process for producing the same, and cerebral function-improving agent comprising the same
    Patent number: 5612381
    Abstract: This invention relates to a 1,2-ethanediol derivative and a salt thereof, a process for producing the same, and a cerebral function-improving agent comprising the same. The cerebral function-improving agent of this invention is useful for treating cerebrovascular dementia, senile dementia, Alzheimer's dementia, sequelae of ischemic encephalopathy and cerebral apoplexy.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: March 18, 1997
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Satoshi Ono, Tetsuo Yamafuji, Hisaaki Chaki, Mutsuko Maekawa, Yozo Todo, Hirokazu Narita
  • 1,2-ethanediol derivative and salt thereof and cerebral function-improving agent comprising the same
    Patent number: 5472984
    Abstract: This invention relates to a 1,2-ethanediol derivative and a salt thereof, a process for producing the same, and a cerebral function-improving agent comprising the same. The cerebral function-improving agent of this invention is useful for treating cerebrovascular dementia, senile dementia, Alzheimer's dementia, sequelae of ischemic encephalopathy and cerebral apoplexy.
    Type: Grant
    Filed: December 29, 1993
    Date of Patent: December 5, 1995
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Satoshi Ono, Tetsuo Yamafuji, Hisaaki Chaki, Mutsuko Maekawa, Yozo Todo, Hirokazu Narita
  • Benzo[b]thiophen-5-yl derivative and process for producing the same
    Patent number: 5380878
    Abstract: This invention relates to a process for producing a compound represented by formula (6a) or (6b): ##STR1## wherein R.sup.2 represents a hydrogen atom or a hydroxyl-protecting group and R.sup.4 and R.sup.5, which may be the same or different, represents lower alkyl groups, using a compound represented by formula (2a) or (2b) obtained by preferential crystallization: ##STR2## and also to a compound represented by the following formula (7) which is an intermediate useful for producing the compound of formula (6a) or (6b): ##STR3## wherein R.sup.1 represents a group represented by formula (8): ##STR4## wherein R.sup.2 and R.sup.3 is as defined above and R.sup.3 represents a hydrogen atom, a group or a carboxyl protecting group represented by formula (9): ##STR5## or a group represented by formula (10): ##STR6## wherein R.sup.2 is as defined above.
    Type: Grant
    Filed: March 29, 1994
    Date of Patent: January 10, 1995
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Joji Nakano, Nobuhisa Taya, Hisaaki Chaki, Tetsuo Yamafuji, Kaishu Momonoi
  • 1,2-ethanediol derivative and salt thereof, process for producing the same, and cerebral function-improving agent comprising the same
    Patent number: 5280032
    Abstract: This invention relates to a 1,2-ethanediol derivative and a salt thereof, a process for producing the same, and a cerebral function improving agent comprising the same. The cerebral function-improving agent of this invention is useful for treating cerebrovascular dementia, senile dementia, Alzheimer's dementia, sequelae of ischemic encephalopathy and cerebral apoplexy.
    Type: Grant
    Filed: September 8, 1992
    Date of Patent: January 18, 1994
    Assignee: Toyama Chemical Co., Ltd.
    Inventors: Satoshi Ono, Tetsuo Yamafuji, Hisaaki Chaki, Mutsuko Maekawa, Yozo Todo, Hirokazu Narita
  • Nicotinic acid derivatives
    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
  • Process for producing 1-substituted aryl-1,4-dihydro-4-oxonaphthyridine derivatives, and processes for producing the intermediates
    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