4-SUBSTITUTED ANTHRACYCLINONES AND ANTHRACYCLINE GLYCOSIDES AND THE PROCESS FOR PREPARING THEM

摘要

4-substituted anthracyclinones of formula (I): wherein R represents a straight or branched alkyl, alkenyl or alkynyl group of up to 16 carbon atoms optionally substituted by (a) an aryl group which is unsubstituted or substituted by an inert group such as an alkyl, alkoxy or nitro group; (b) an alkoxy group; (c) a trialkylsilyl group, (d) an ester group or (e) an amido group, are intermediates in the preparation of antitumor anthracycline glycosides of formula (IX): wherein R is as defined above and R1 is a hydrogen atom or a hydroxy group, and pharmaceutically acceptable salts thereof.