Synthetic Study on Peptide Antibiotic Nisin. I. The Synthesis of Ring A

Abstract

Abstract Synthesis of the ring A, a cyclic sulfide peptide part containing dehydroalanine residue, in peptide antibiotic nisin was successfully achieved by applications of two novel procedures. First, a sulfide ring was derived from a cyclic disulfide peptide by desulfurization with P(Et2N)3. Secondly, for the preparation of dehydroalanyl residue, a simple and convenient method through Hofmann degradation of 2,3-diaminopropionyl residue was newly exploited in the presence of sulfide linkage.