Synthesis and Biological Evaluation of Novel 2-Substituted Analogues of (-)-Pentenomycin I

A library of novel 2-substituted derivatives of the antibiotic natural product pentenomycin I is presented. The new collection of analogues is divided in two main classes, 2-alkynyl- and 2-aryl- derivatives, which are accessed by the appropriate type of palladium-catalyzed cross-coupling reaction of the 2-iodo-protected pentenomycin I with suitable nucleophiles. The new derivatives were tested for their activity against certain types of bacteria and one of them, compound 8h , was found to exhibit significant inhibitory activity against several Gram-positive bacteria but also displayed cytotoxic activity against eukaryotic cell lines.