Patent ID: 7098338

Claim:
A compound of formula I having the structure wherein R is hydrogen or alkyl of 1–6 carbon atoms; R′ is hydrogen, alkyl of 1–6 carbon atoms, acyl of 2–7 carbon atoms, or aroyl; R 1 , R 2 , R 3 , and R 4 are each, independently, hydrogen, alkyl of 1–6 carbon atoms, alkoxy of 1–6 carbon atoms, halogen, trifluoroalkyl, or trifluoroalkoxy of 1–6 carbon atoms; X is CR 5 R 6 or a carbonyl group; R 5 and R 6 are each, independently, hydrogen or alkyl of 1–6 carbon atoms; with the proviso that at least two of R 1 , R 2 , R 3 , or R 4 are not hydrogen, and that when X is a carbonyl group, R 2 and R 3 are not both halogen; or a pharmaceutically acceptable salt thereof.