Patent ID: 6890917

Claim:
A compound having the formula: wherein n=0 or 1 and wherein, when n=1, each of R 1 and R 2 is hydrogen, and, when n=0, a double-bond exists between C 4 and C 5 ; R 3 is hydrogen or hydroxyl; R 4 is hydrogen or hydroxyl; wherein, when R 3 is hydrogen, R 4 is hydroxyl, and when R 3 is hydroxyl, R 4 is hydrogen; and R 5 is hydrogen or a group of the formula wherein each of R 6 , R 7 , and R 8 is independently selected from the group consisting of hydrogen, halo, azido, nitro, a C 1 -C 8 alkyl, a C 1 -C 8 alkoxy, aryl, cyano, and NR 10 R 11 , wherein each of R 10 and R 11 is independently selected from the group consisting of hydrogen and a C 1 -C 3 alkyl; or a pharmaceutically acceptable salt thereof.