new derivatives of 16 acythio fusidic acid, useful as antimicrobial agents, and their method of preparation

摘要

The present invention relates to a new series of fusidic acid derivatives, to salts and easily hydrolysable esters thereof, to the preparation of these compounds, and to pharmaceutical compositions containing the compounds, the new fusidic acid derivatives having the general formula: IMAGE I in which the dotted line between C-24 and C-25 indicates that the carbon atoms in question are connected by either a double bond or a single bond, and in which Q1 represents oxygen or one of the groupings IMAGE Z being a hydroxy group, a halogen atom, an alkylsulfonyloxy or arylsulfonyloxy group, such as methanesulfonyloxy or p-toluenesulfonyloxy, an azido or a nitro group, Q2 is oxygen or the grouping IMAGE and R1stands for a straight or branched alkyl radical having from 1 to 6 carbon atoms, such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl or the known isomers of pentyl and hexyl, a phenyl or a heterocyclyl radical having 5 to 6 ring atoms and containing nitrogen, oxygen and/or sulfur atoms, these radicals being optionally substituted with halogen, nitro, lower alkyl or lower alkoxy radicals.