Patent ID: 7732434

Claim:
A compound of the Formula (I); or a stereoisomer thereof wherein represents a single or double bond; R 1 and R 2 are independently hydrogen, halogen, C 1-4 alkyl or CF 3 ; R 3 is hydrogen, C 1-4 alkyl, fluoro C 1-4 alkyl, CF 3 or benzyl; R 4 is hydrogen, C 1-4 alkyl or phenyl in which each is optionally substituted with halogen, C 1-4 alkyl or C 1-4 alkoxy; R 5 is hydrogen, halogen, CF 3 , OH, NH 2 , C 1-4 alkyl or C 1-4 alkoxy; n is an integer of 1, 2, 3 or 4; and X is O or S; or a nontoxic pharmaceutically acceptable salt thereof.