New pleuromutilin derivatives with enhanced antimicrobial activity. I. Synthesis.

A series of new derivatives of the antibiotic pleuromutilin, produced by some Basidiomycetes, was synthesized by chemical modification of natural pleuromutilin. Most of them contain basic functional groups in the side chain at C14 of the mutilin skeleton. The monotosylate of pleuromutilin was used as a versatile intermediate for displacement by N-, O- and S-nucleophiles.