Antimicrobial Activity of Basic Cholane Derivatives Part IX

Twenty new compounds derived from deoxycholic acid have been synthesized. They contain two basic functions: at C‐24 (benzylamino, morpholino, diethanolamino, N,N‐diethylethylenediamino, N‐methylpiperazino) and at β‐C‐3 (amino, methylamino, ethylamino, benzylamino). The compounds showed interesting antimicrobial activity, as expressed in terms of the low M.I.C. values (0.9‐31‐μ/ml) against five Gram (+) and four Gram (−) strains, two fungi and one yeast. The compounds inhibit the production of a fluorescent pigment in Pseudomonas aeruginosa : this result suggests that the ability to cross the bacterium cell membrane is the first step of activity. A discussion in terms of structure‐activity relationship is reported.