Patent ID: 7767685

Claim:
A compound of the formula wherein R 1 and R 2 are, independently from each other, C 1 -C 6 alkyl optionally substituted by C 1 -C 4 alkoxy, C 3 -C 6 cycloalkyl, C 2 -C 4 alkenyl, C 2 -C 4 alkynyl or monocyclic aryl that may be optionally substituted by 1-3 substituents selected from the group consisting of C 1 -C 4 alkyl, trifluoromethyl, halo, hydroxy, C 1 -C 4 alkoxy, methylenedioxy, C 1 -C 4 alkylthio, cyano, carboxy, C 1 -C 4 alkoxycarbonyl, C 1 -C 4 alkylthiono or C 1 -C 4 alkylsulfonyl; R 3 is hydrogen or halogen; R 4 and R 5 are, independently from each other, hydrogen or C 1 -C 4 alkyl; R 6 is aryl or heteroaryl each of which may be optionally substituted by 1-3 substituents selected from the group consisting of C 1 -C 6 alkyl, trifluoromethyl, C 3 -C 6 cycloalkyl, halo, hydroxy, C 1 -C 6 alkoxy, methylenedioxy, ethylenedioxy, C 1 -C 6 alkanoyl, C 1 -C 6 alkanoyloxy, C 6 -C 10 aryloxy, amino, C 1 -C 6 alkylamino, di(C 1 -C 6 alkyl)amino, C 1 -C 6 alkylthio, C 6 -C 10 arylthio, nitro, cyano, carboxy, C 1 -C 6 alkoxycarbonyl, carbamoyl, C 1 -C 6 alkylthiono, C 1 -C 6 alkylsulfonyl or C 6 -C 10 arylsulfonyl; or a pharmaceutically acceptable salt thereof.