Patents by Inventor Masaki Yokota

Masaki Yokota 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).

  • Substituted tetrahydroisoquinoline compounds and method containing them
    Patent number: 5079256
    Abstract: A compound of the formula (I) or its salt and a process for producing the compounds. The compounds have the effect of dilating neophrovascular tracts; ##STR1## wherein ##STR2## represents the formula ##STR3## wherein R.sup.4 is a hydrogen atom or lower alkylsulfonyl;R.sup.1 is hydrogen, lower alkyl, hydroxyl, halogen, amino, or lower acylamino;R.sup.2 is hydrogen, lower alkyl, hydroxyl, amino, or lower alkylsulfonylamino;R.sup.3 is hydrogen, lower alkyl, or hydroxyl;R is hydrogen or halogen;with the proviso that when R.sup.1 is hydroxyl, there is no case that all of R.sup.2, R.sup.3 and R are hydrogens, and further with the proviso that when R is hydrogen, A excludes ##STR4## or a salt thereof.
    Type: Grant
    Filed: September 26, 1989
    Date of Patent: January 7, 1992
    Assignee: Yamanouchi Pharmaceutical Co., Ltd.
    Inventors: Akihiro Tanaka, Takashi Fujikura, Ryuji Tsuzuki, Masaki Yokota, Takeyuki Yatsu
  • Production of 2-amino-7-(6-fluoro-3,4-hydroxyphenyl)-4,5,6,7-tetrahydrothiazolo[4,5-c] pyridine dihydrobromide
    Patent number: 5077406
    Abstract: A compound of the formula (I) or its salt and a process for producing the compounds; The compounds have the effect to dilate neophrovascular tracts; ##STR1## wherein ##STR2## represents the formula ##STR3## (wherein R.sup.4 is a hydrogen atom or lower alkylsulfonyl); R.sup.1 is hydrogen, lower alkyl, hydroxyl, halogen, amino, or lower acylamino;R.sup.2 is hydrogen, lower alkyl, hydroxyl, amino, or lower alkysulfonylamino;R.sup.3 is hydrogen, lower alkyl, or hydroxyl;R is hydrogen or halogen;with the proviso that when R.sup.1 is hydroxyl, there is no case that all of R.sup.2, R.sup.3 and R are hydrogens, and further with the proviso that when R is hydrogen. A excludes ##STR4## or a salt thereof.
    Type: Grant
    Filed: May 3, 1990
    Date of Patent: December 31, 1991
    Assignee: Yamanouchi Pharmaceutical Co., Ltd.
    Inventors: Akihiro Tanaka, Takashi Fujikura, Ryuji Tsuzuki, Masaki Yokota, Takeyuki Yatsu
  • Substituted tetrahydroisoquinoline compounds, and process for producing them, and composition containing them
    Patent number: 4966904
    Abstract: A compound of the formula (I) or its salt and a process for producing the compounds; The compounds have the effect to dilate neophrovascular tracts; ##STR1## Wherein ##STR2## represents the formula ##STR3## (wherein R.sup.4 is a hydrogen atom or lower alkylsulfonyl); R.sup.1 is hydrogen, lower alkyl, hydroxyl, halogen, amino, or lower acylamino;R.sup.2 is hydrogen, lower alkyl, hydroxyl, amino, or lower alkylsulfonylamino;R.sup.3 is hydrogen, lower alkyl, or hydroxyl;R is hydrogen or halogen;with the proviso that when R.sup.1 is hydroxyl, there is no case that all of R.sup.2, R.sup.3 and R are hydrogens, and further with the proviso that when R is hydrogen, A excludes ##STR4## or a salt therof.
    Type: Grant
    Filed: March 9, 1989
    Date of Patent: October 30, 1990
    Assignee: Yamanouchi Pharmaceutical Co., Ltd.
    Inventors: Akihiro Tanaka, Takashi Fujikura, Ryuji Tsuzuki, Masaki Yokota, Takeyuki Yatsu
  • Substituted tetrahydroisoquinoline compounds and composition containing them
    Patent number: 4876261
    Abstract: A compound of the formula (I) or its salt and a process for producing the compounds; The compounds have the effect to dilate neophrovascular tracts; ##STR1## wherein ##STR2## represents the formula ##STR3## (wherein R.sup.4 is a hydrogen atom or lower alkylsulfonyl); R.sup.1 is hydrogen, lower alkyl, hydroxyl, halogen, amino, or lower acylamino;R.sup.2 is hydrogen, lower alkyl, hydroxyl, amino, or lower alkylsulfonylamino;R.sup.3 is hydrogen, lower, alkyl or hydroxyl;R is hydrogen or halogen;with the proviso that when R.sup.1 is hydroxyl, there is no case that all of R.sup.2, R.sup.3 and R are hydrogens, and further with the proviso that when R is hydrogen, A excludes ##STR4## or a salt thereof.
    Type: Grant
    Filed: March 25, 1988
    Date of Patent: October 24, 1989
    Inventors: Akihiro Tanaka, Takashi Fujikura, Ryuji Tsuzuki, Masaki Yokota, Takeyuki Yatsu