| abstract |
A compound having the following structure (I): ** Formula ** or a pharmaceutically acceptable salt or stereoisomer thereof, wherein R1 and R2 are each independently hydrogen, hydroxy, alkyl or alkoxy, with the proviso that at least one of R1 and R2 is hydroxy or alkoxy; A is -CHR3-, -C (R4) (R5) NR6-, -NR6C (R4) (R5) -, -C (> = 0) - or -C (> = N-OR6) -; R3 is -OR6, -OC (> = O) R6 or -NR6R7; R4 and R5 are each hydrogen or both R4 and R5 can be considered together to form an oxo moiety; and R6 and R7 are, at each occurrence, independently, hydrogen, alkyl, optionally substituted aryl or optionally substituted aralkyl. |