Abstract
[Image: see text] We report crystallographic data for a set of homologous γ-peptides that contain a Boc-protected residue derived from the flexible gabapentin monomer at the N-terminus and cyclically constrained γ-residues at all other positions. The crystallized γ-peptides range in length from 3 to 7 residues. Previously only one atomic-resolution structure had been available for a short γ-peptide 14-helix. The new data provided here allow derivation of characteristic parameters for the γ-peptide 14-helix, and establish guidelines for characterizing 14-helical folding in solution via 2D NMR. In addition, the results suggest that the substitution pattern of a γ-residue has a profound effect on the propensity for 14-helical folding.