Impact of γ-Amino Acid Residue Preorganization on α/γ-Peptide Foldamer Helicity in Aqueous Solution.

ABSTRACT: α/γ-Peptide foldamers containing either γ(4)-amino acid residues or ring-constrained γ-amino acid residues have been reported to adopt 12-helical secondary structure in nonpolar solvents and in the solid state. These observations have engendered speculation that the seemingly flexible γ(4) residues have a high intrinsic helical propensity and that residue-based preorganization may not significantly stabilize the 12-helical conformation. However, the prior studies were conducted in environments that favor intramolecular H-bond formation. Here, we use 2D-NMR to compare the ability of γ(4) residues and cyclic γ residues to support 12-helix formation in more challenging environments, methanol and water. Both γ residue types support 12-helical folding in methanol, but only the cyclically constr

SUBMITTER: Fisher BF 

PROVIDER: S-EPMC5972013 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature