Synthesis and structure-mechanical property correlation of an α,β-hybrid peptide containing methyl-3-aminocrotonate

Abstract

An α,β-hybrid peptide has been synthesized and the structure-mechanical property correlation of the peptide has been presented. The α,β-hybrid peptide 1 has L-Phe and methyl-3-aminocrotonate residues and formed monoclinic crystals, with space group P 21/n. From X-ray crystallography analysis, there is a five-member NH⋯N and a six-member intramolecular NH⋯O=C hydrogen bond and the α,β-hybrid peptide 1 adopts a turn-like conformation, due to the trans geometry of the methyl-3-aminocrotonate residue. The α,β-hybrid peptide 1 molecules self-assemble by intermolecular N-H⋯O hydrogen bonds and form a supramolecular twisted sheet-like structure which further assembled to form a supramolecular malty layers structure along the crystallographic b and c directions.However, the α,β-hybrid peptide 1 crystals are sensitive to external stress and brittle in nature. From FE-SEM the crystal appears as a layer by layer structure. The intermolecular interaction energies (kJ/mol) for the α,β-hybrid peptide 1 were calculated using B3LYP/6-31G(d,p) dispersion corrected DFT model. Although the interaction energy is small, there is no scope of slippage due to the interaction of the Boc t-butyl, Phe side chains and methyl-3-aminocrotonate in the malty layer sheets.

URN:NBN:sciencein.jmc.2022.326