| abstract |
A compound represented by formula 1: ** (See formula) ** in which: R1 is O, (H, H), (H, OH) or NOR, where R is hydrogen, (C1-C6) alkyl, or acyl of (C1-C6); R2 is hydrogen, methyl, ethyl or ethenyl; R3 is hydrogen, methyl, ethyl, ethenyl, fluorine or chlorine; R4 is methyl or ethyl; R5 is hydrogen, methyl or ethyl; R6 is hydrogen, methyl, ethyl, (C2-C3) alkenyl, C2-C3 alkynyl; R7 is hydrogen or C1-C15 acyl; and at least one between R5 or R6 is hydrogen; and pharmaceutically acceptable salts thereof. |