Patent ID: 6861436

Claim:
A compound represented by the following structural formula: or a pharmaceutically acceptable salt thereof, wherein: Ring A is substituted or unsubstituted and is optionally fused to an aryl group; Z 1 and Z 2 are independently ═O, ═S, ═N—OR 12 or ═NR 12 ; R 1 and R 2 are independently —H, an aliphatic group, a substituted aliphatic group, or a substituted or unsubstituted aryl group selected from: provided that R 1 and R 2 are not both —H; R 3 is a substituted or unsubstituted aliphatic group or a substituted or unsubstituted aryl group represented by Ring V: wherein Z is —O—, —S—, —NR—, or —CH═CH— and R is —H or C1-C4 alkyl; X is a covalent bond, —C(R 4 R 5 )—, —N(R 4 )—, —O—, —S—, —S(O)—, —S(O) 2 —, —C(═O)—, —C(═O)—N(R 4 )—, or —N(R 4 )—C(═O)—, R 4 and R 5 are independently —H or a substituted or unsubstituted aliphatic group; and R 12 is —H or a substituted or unsubstituted alkyl group.