| 摘要 |
Novel compounds of the following formula: <IMAGE> wherein R1 is hydrogen or hydroxy; R2 is hydrogen; or R1 and R2 taken together form a second bond between the carbon atoms bearing R1 and R2; n is an integer of from 1 to 5; R3 is -CH3, -CH2OH, -COOH or -COOalkyl wherein the alkyl moiety has from 1 to 6 carbon atoms and is straight or branched; and each of A and B is hydrogen or hydroxy; with the provisos that at least one of A or B is hydrogen and one of A or B is other than hydrogen when R3 is -CH3; and pharmaceutically acceptable salts thereof. |
