Peptide β-Bend and 3-10-Helix: from 3D-Structural Studies to Applications as Templates

The 3 10-helix is a relatively common secondary structure motif in peptides and proteins. Its building block is one of various types of -bend conformation which comprises an N -acylated dipeptide alkylamide system. A complete 3D-structural characterization of this ternary helix has been achieved, thus allowing its unambiguous discrimination from the closely related -helix. Recent applications of rigidified peptide -bends and 3 10-helices as templates for investigations in synthetic organic chemistry (macrocyclization, catalysis), host–guest chemistry (molecular recognition), and physical chemistry (donor–acceptor interaction) will be discussed.