Patents Examined by Philip I. Patton
  • Tetracyclic compounds having anti-allergic and anti-asthmatic activities and their use
    Patent number: 5461051
    Abstract: Compounds of formula (I): ##STR1## in which: Q is nitrogen or .dbd.CH--; R.sup.1 and R.sup.2 are hydrogen, alkyl, alkoxy, hydroxy, trifluoromethyl or halogen; and R.sup.3 is a substituted alkyl groups, or a pharmaceutically acceptable salt thereof have valuable anti-allergic and anti-asthmatic activities. The compounds are prepared by reacting a corresponding compound where R.sup.3 is replaced by a hydrogen atom with a compound to introduce the group R.sup.3.
    Type: Grant
    Filed: June 28, 1994
    Date of Patent: October 24, 1995
    Assignee: Sankyo Company, Limited
    Inventors: Hiroshi Fukumi, Toshiaki Sakamoto, Mitsuo Sugiyama, Yoshio Iizuka, Takeshi Yamaguchi