Patent ID: 7488720

Claim:
A compound of Formula I: wherein: R is hydrogen or lower alkyl; R 1 is alkyl, cycloalkyl, aryl, heterocyclyl, or heteroaryl; R 2 is alkyl substituted by —SO 3 H, cycloalkyl substituted by —SO 3 H, aryl substituted by —SO 3 H, heteroaryl substituted by —SO 3 H, or heterocyclyl substituted by —SO 3 H; R 3 is —CH 2 OR 6 or —C(O)NR 7 R 8 ; in which R 6 is hydrogen or acyl, and R 7 and R 8 are independently hydrogen or lower alkyl; R 4 and R 5 are independently hydrogen or lower alkyl; and Y is a covalent bond or alkylene; or a pharmaceutically acceptable salt thereof.