Rigid dipeptides mimicking the polyproline II helix

摘要

Backbone amide hdyrogen bonds stabilize alpha-helical structures but no such stabilisation is available for polyproline II (PPII) helical structures because the amide bonds are not oriented parallel but perpendicular to the helix axis.Either triple helix formation-as in collagen-or other intermolecular constacts stabilize PPII helical peptide conformations.