Synthesis and Structure of Chiral Methoxypyrrole Amino Acids (MOPAS)

Abstract

A methoxypyrrole amino acid (MOPAS) resembling the structure of H2N-Val-Δ-Ala-OEt in β-sheet conformation has been prepared by a chiral auxiliary approach. The X-ray structure analysis confirms the absolute configuration of the dipeptide mimic. Standard peptide coupling procedures allow coupling of the chiral MOPAS with natural amino acids or their extension by additional MOPAS units. A tight self-association of bis-MOPAS 13 in CDCl3 and the affinity to Ac-Ala-Ile-OMe dipeptides illustrates the ability of the constrained dipeptide mimic MOPAS to interact with peptides.