Conformation of dehydropentapeptides containing four achiral amino acid residues – controlling the role of L-valine

• Michał Jewgiński,
• Joanna Krzciuk-Gula,
• Maciej Makowski,
• Rafał Latajka and
• Paweł Kafarski

Beilstein J. Org. Chem. 2014, 10, 660–666, doi:10.3762/bjoc.10.58

• right-handed helical conformation. Keywords: conformation; dehydroalanine; dehydropeptide; dehydrophenylalanine; NMR; Introduction Structurally modified peptides are becoming increasingly interesting as potential substances with pharmacological effects [1]. Dehydropeptides are one representative of

• the whole dehydropeptide [4][5][6][7]. It is noteworthy that the introduction of dehydroamino acid residues has a strong influence on the conformational preference of the peptide chain, irrespective of other constraints. The introduction of (Z)-dehydrophenylalanine stabilizes a β-turn conformation

• and co-workers described that the insertion of an ester at the chiral residue of the dehydropeptide sequence induces left-handed helical structures. However, in the case of peptide 3, the analysis of the torsion angle values of the main chain clearly indicates that the insertion of one chiral L-Val