4'-O-Acyl derivatives of doxorubicin, daunorubicin, 13-deoxocarminomycin, 13-deoxo-10-hydroxycarminomycin, 13-deoxo-11-deoxycarminomycin were synthesized through the formation and mild acid hydrolysis of 2-oxazoline intermediates. The antitumor activity of these 4'-O-acyl derivatives against P388 leukemia was similar to or more effective than the parent anthracyclines.