METHOD FOR THE INTRODUCTION OF AN OXYGEN-CONTAINING FUNCTIONAL GROUP INTO ANSAMYCINES, COMPOUNDS THUS OBTAINED, AND PHARMACEUTICAL COMPOSITIONS CONTAINING THEM

摘要

1. A rifamycin S derivative of the formula (I) see diagramm : EP0023885,P9,F1 wherein each of R and R' is a hydrogen atom or R' is acetyl and R is a radical selected from Alk, Ar, Alk-CO-, Ar-CO- or H-CO-, in which Alk is a C1 -C7 alkyl radical, 2-methoxymethyl, 2-ethoxyethyl, 2-hydroxyethyl, 2- or 3-hydroxypropyl or 4-hydroxybutyl, in which the hydroxyl group can also be esterified by formic acid or a C1 -C7 alkanecarboxylic acid, and Ar is a phenyl radical which is unsubstituted or substituted by C1 -C7 alkyl, C1 -C7 alkoxy, methylenedioxy or formyl, or a corresponding derivative of the SV series.