Patent ID: 7282608

Claim:
A compound of formula: or a pharmaceutically acceptable salt thereof, wherein Y is —N(R 4 )—, —O—, —S—, —N(R 4 )SO 2 —, —SO 2 —N(R 4 ) —, —SO 2 —, —N(R 4 )—C(O)—, —C(O)—N(R 4 )—, —NHC(O)NH—, —N(R 4 )C(O)O—, —OC(O)N(R 4 )—, or a covalent bond, and R 1 , R 2 , and R 3 independently are —H or R a —C 0 –C 6 -hydrocarbyl wherein R a is —H or R a is aryl or heteroaryl, each of which is optionally substituted with from 1 to 3 substituents, R 4 is —H, —C(O)—R b , —C(O)O—R b , —C(O)NH—R b , or R c –C 0 –C 6 -hydrocarbyl wherein R b is —H or —C 1 –C 6 -hydrocarbyl, and R c is —H, or aryl or heteroaryl each of which is optionally substituted with from 1 to 3 substituents.