Association of model peptides and dehydropeptides: N-acetyl-L-butyrine and (Z)-dehydrobutyrine N',N'-dimethylamides.

Abstract

These comparative studies on the aggregation behaviour of Ac-(Z)-DeltaAbu-NMe(2) and Ac-L-Abu-NMe(2) in carbon tetrachloride were performed by the analysis of their FTIR spectra and by theoretical calculations. The percentage of the monomeric form (alpha) decreased as concentration increased and this occurred to a higher degree for the (Z)-DeltaAbu derivative than for its saturated analogue. The dimerization constant K(D), calculated on the basis of the intensity of the monomer and associate bands in the nu(s)(N-H) vibration region, is by three orders of magnitude larger for Ac-(Z)-DeltaAbu-NMe(2) than for Ac-L-Abu-NMe(2). The obtained dimer geometries of the dehydro- compound were calculated by the B3LYP/6-31+G** method.

Conformational study of poly‐ΔAbu peptides and construction of amphipathic nanostructure

“…Dehydroamino acids are generally used in the Z‐ isomer, possibly because of their convenient chemical synthesis. α,β‐dehydroamino acid residues in the E‐ form are less common and possibly because of this reason, their synthetic routes have not yet been explored and little is known about their conformational preferences 29, 30. Thus, it is worth investigating the conformational behavior of the simplest dehydroamino acid‐ΔAbu in both Z‐ and E‐ forms (see Figure 1).…”