Patent number: 4429133
Abstract: Disclosed are compounds of Formula I, ##STR1## where either R.sub.1, R.sub.2, R.sub.3 and R.sub.4, independently, are hydrogen, C.sub.1-4 alkyl, C.sub.1-4 alkoxy, halogen, cyano, carboxy, alkoxy(C.sub.1-4)carbonyl, --CONR.sub.6 R.sub.7, --SO.sub.2 NR.sub.6 R.sub.7, --SO.sub.2 R.sub.8, alkyl(C.sub.1-4)carbonyloxy, or C.sub.1-4 alkoxy monosubstituted by phenyl, alkoxy(C.sub.1-4)carbonyl, cyano, carboxy or --CONR.sub.6 R.sub.7,with the proviso that a maximum of one of R.sub.1 and R.sub.2 and a maximum of one of R.sub.3 and R.sub.4 can signify a group selected from cyano, carboxy, alkyl (C.sub.1-4)carbonyloxy, --CONR.sub.6 R.sub.7, --SO.sub.2 NR.sub.6 R.sub.7 and --SO.sub.2 R.sub.8,or one or both pairs R.sub.1 and R.sub.2, and R.sub.3 and R.sub.4, are on adjacent carbon atoms and form a fused benzene ring, any pair not forming a ring being as defined above,R.sub.5 is C.sub.1-4 alkyl, unsubstituted or mono-substituted by hydroxy, cyano, phenyl, C.sub.2-4 alkenyl, carboxy, C.sub.1-4 alkoxycarbonyl or --CONR.sub.
Type:
Grant
Filed:
July 28, 1977
Date of Patent:
January 31, 1984
Assignee:
Sandoz Ltd.
Inventor:
Peter S. Littlewood