Patent ID: 8247420

Claim:
A compound having structural Formula (II): or a pharmaceutically acceptable salt thereof, wherein X is O, S, NH or NR 8 ; SP is a spacer selected from the group consisting of O, S, alkyl, substituted alkyl, acylamino, alkoxy, alkylamino, alkylthio, or aryloxyalkyl; A is —O—(CH 2 ) n —, wherein n is an integer between 1 and 7; R 2 , R 3 , R 4 , R 5 and R 6 are independently selected from the group consisting of hydrogen, alkyl, substituted alkyl, aryl, substituted aryl, arylalkyl, substituted arylalkyl, cycloalkyl, substituted cycloalkyl, alkoxy, alkylsulfinyl, alkylsulfonyl, alkylthio, amino, alkylamino, arylalkylamino, dialkylamino, arylalkoxy, cyano, halogen, or hydroxy, wherein R 4 and R 5 are optionally present on the same carbon; R 7 is alkyl, substituted alkyl, aryl, substituted aryl, arylalkyl, substituted arylalkyl, cycloalkyl, or substituted cycloalkyl; and R 8 is alkyl, or substituted alkyl.