Patent ID: 6943158

Claim:
A compound of the formula: or a pharmaceutically acceptable salt thereof, wherein R 1 is hydrogen or alkyl; R 2 is alkyl, haloalkyl, aryl, aralkyl, heteroaryl, heteroaralkyl, cycloalkyl, cycloalkylalkyl, heteroalkylsubstituted cycloalkyl, heterosubstituted cycloalkyl, heteroalkyl, cyanoalkyl, heterocyclyl, heterocyclylalkyl, or —Y 1 —C(O)—Y 2 —R 11 (where Y 1 and Y 2 are independently either absent or an alkylene group and R 11 is hydrogen, alkyl, haloalkyl, hydroxy, alkoxy, amino, monoalkylamino or dialkylamino); R 3 is hydrogen, alkyl, cycloalkyl, cycloalkylalkyl, heterosubstituted cycloalkyl, heterocyclyl, aryl, aralkyl, haloalkyl, heteroalkyl, cyanoalkyl, -alkylene-C(═O)—R 4 (where R 4 is hydrogen, alkyl, hydroxy, alkoxy, amino, monoalkylamino or dialkylamino), or acyl; Ar 1 is aryl; X 1 is O, NR 5 or S, where R 5 is hydrogen or alkyl; and X 2 is a bond, O, NR 6 , S or CH 2 , where R 6 is hydrogen or alkyl.