Dehydrooligopeptides. XVI. Convenient Syntheses of Two Kinds of Antrimycins Av and Dv Containing Dehydrovaline Residues

Abstract

Abstract Eight kinds of peptide antibiotics, antrimycins (1), consist of four sorts of unusual α-amino acids, that is, hydroxymethylserine, (2S,3S)-2,3-diaminobutanoic acid, (S)-2,3,4,5-tetrahydro-3-pyridazinecarboxylic acid, and dehydrovaline (ΔVal) or (E)-dehydroisoleucine (ΔIle) from the N-terminus of 1. The practical syntheses of the three segments containing these four acids, and all of the protected 1 by the usual fragment condensations of the three segments were accomplished. Moreover, after mild deprotection of the protecting groups, the two kinds of 1, antrimycins Av and Dv comprising Ala5–ΔVal6 and Leu5–ΔVal6 segments respectively, were synthesized.