Patent ID: 8754127

Claim:
A compound of formula I: wherein X is C 1 -C 3 alkylene, optionally substituted with one, two or three substituents selected from halogen or hydroxyl; R 1 is selected from the group consisting of C 1 -C 6 alkyl, C 3 -C 6 cycloalkyl, C 2 -C 6 alkenyl, and C 2 -C 6 alkynyl; R 2 is selected from the group consisting of hydrogen and C 1 -C 6 alkyl; R 3 is independently selected, for each occurrence from the group consisting of hydrogen, C 1 -C 6 alkyl, cyano, C 3 -C 6 cycloalkyl, hydroxyl, and nitro; R 4 is selected from the group consisting of hydrogen and C 1 -C 6 alkyl; R 5 is hydrogen or C 1 -C 6 alkyl; or pharmaceutically acceptable salts or N-oxides thereof.