6,7,8,9-tetrahydropyrido1,2-a indole derivatives

Abstract From the Canadian patent

A pharmaceutical composition comprising a compound of formula (I) or a pharmaceutically acceptable salt thereof:, (I), wherein:, R1 is hydrogen C1-6 alkyl, C1-6 alkoxy or halogen;, R2 and R3 are both hydrogen or together represent a bond;, R4 is hydrogen and R5 is hydrogen or R4 and R5 together represent an oxo group;, R6 is hydrogen; C1-6 alkyl; C3-7 cycloalkyl; C3-7 cycloalkyl-C1-4 alkyl; phenyl or phenyl C1-7 alkyl in which the phenyl moiety is optionally substituted by one or two of halogen, ortho-nitro, meta-or para-methoxy, methyl or NR8R9 wherein R8 and R9 are independently hydrogen or C1-6 alkyl or R8 and R9 together are C2-6 polymethylene, or 3,4-disubstituted by methylenedioxy or …