Process for the preparation of anthracyclinones

摘要

The present invention relates to a new process for the preparation of anthracyclinones of the formula <IMAGE> I in which R denotes C1-C4-alkyl, R1 denotes H or OH, and R2 and R3 are different and each represent H or OH, and R4 and R5 are different and each represent H or OH, starting from a compound of the formula <IMAGE> II in which R1 and R have the abovementioned meaning. The compounds of the formula I are valuable intermediates in the preparation of the corresponding glycosides having cytostatic efficacy.