Abstract: Novel compounds of the following formula: ##STR1## wherein R.sub.1 is hydrogen or hydroxy; R.sub.2 is hydrogen; or R.sub.1 and R.sub.2 taken together form a second bond between the carbon atoms bearing R.sub.1 and R.sub.2 ; n is an integer of from 1 to 5; R.sub.3 is --CH.sub.3, --CH.sub.2 OH, --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 R.sub.3 is --CH.sub.3 ; and pharmaceutically acceptable salts thereof.