Patent ID: 7501512

Claim:
A compound of the formula I, or a salt thereof in which R1 is hydrogen, —NH 2 , or C 1-6 alkyl; R2 is hydrogen; or R2 is a radical of the formula in which W is a bond, —CH 2 —, —CH 2 CH 2 —, —C(═O)—, —NCH 3 —, or —NH—; R is phenyl optionally and independently substituted with one to three C 1-6 alkyl, halogen, C 1-6 alkylO—, C 1-6 alkylOC(═O)—, acetyl, NH 2 C(═O)—, FSO 2 —, —CF 3 , NH 2 SO 2 —, dimethylamino; HOCH 2 —, CH 3 NHC(═O)—, hydroxy, or phenyl; or R is a radical of the formula provided that W cannot be CH 2 when point of attachment of R to W is oxygen or nitrogen.