Patent ID: 7429666

Claim:
A compound of formula II or a pharmaceutically acceptable salt thereof wherein: R 1 is selected from the group consisting of (1) —C 1-3 alkyl, (2) —OC 1-3 alkyl, (3) —SC 1-3 alkyl, and (4) —C 2-4 alkenyl; wherein definitions (1) to (4) are optionally substituted with 1, 2 or 3 substituents selected from the group consisting of halo, hydroxyl, —CN, —NO 2 , and NH 2 ; R 2 and R 3 are each hydrogen; R 4 and R 5 are each hydrogen; R 6 is hydrogen; k is 1, and Ar and Ar 1 are each independently an phenyl or pyridyl, optionally substituted with 1, 2, or 3 substitents selected from (1) -halo, (2) C 1-4 alkyl, optionally substituted with 1, 2, 3 or 4 halo groups, (3) —NR 7 R 8 , (4) phenyl, (5) —OC 1-4 alkyl, optionally substituted with 1, 2, 3 or 4 halo groups, (6) —SC 1-4 alkyl; and R 7 and R 8 are each independently hydrogen or methyl.