Patent ID: 8067410

Claim:
A compound having the structure I wherein X is absent or oxygen when X is oxygen, R 1 and R 2 are independently selected from hydrogen; C 1 -C 6 alkanoyl; C 6 -C 10 aryl-C 1 -C 6 alkanoyl; or R 1 and R 2 are fused and form a methylene (CH 2 ) group; when X is absent, R 1 is selected from hydrogen; C 1 -C 6 alkyl; C 1 -C 6 alkanoyl; C 6 -C 10 aryl-C 1 -C 6 alkanoyl; and R 2 is hydrogen; R 3 is selected from the group consisting of hydrogen; C 1 -C 4 alkyl; allyl; propargyl; C 3 -C 4 cycloalkyl; hydroxyalkyl; C 2 -C 3 haloalkyl; R 4 is selected from the group consisting of hydrogen; C 1 -C 6 alkyl; C 6 -C 10 aryl-C 1 -C 6 alkyl; heteroaryl-C 1 -C 6 alkyl; di(C 1 -C 6 alkyl)amino-C 1 -C 6 alkyl; C 1 -C 6 alkylthio-C 1 -C 6 alkyl; C 1 -C 6 hydroxyalkyl; and C 1 -C 6 haloalkyl, wherein each C 6 -C 10 aryl and heteroaryl may be substituted with a substituent selected from halogen; C 1 -C 6 alkyl; C 1 -C 6 alkoxy, and enantiomers, diastereomers, tautomers and pharmaceutically acceptable addition salts thereof.