title: Heterogeneous H-bonding in a foldamer helix.
abstract: Structural characterization of new α/γ-peptide foldamers containing the cyclically constrained γ-amino acid I is described. Crystallographic and 2D NMR analysis shows that γ residue I promotes the formation of a 12/10-helical secondary structure in α/γ-peptides. This helix contains two different types of internal H-bond, and the data show that the 12-atom C═O(i) → H-N(i+3) H-bond is more favorable than the 10-atom C═O(i) → H-N(i-1) H-bond. Several foldamer helices featuring topologically distinct H-bonds have been discovered, but our findings are the first to show that such H-bonds may differ in their favorability.
authors.affiliation: Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States.
authors.forename: Brian F
authors.initials: BF
authors.lastname: Fisher
authors.affiliation: Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States.
authors.forename: Li
authors.initials: L
authors.lastname: Guo
authors.affiliation: Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States.
authors.forename: Brian S
authors.initials: BS
authors.lastname: Dolinar
authors.affiliation: Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States.
authors.forename: Ilia A
authors.initials: IA
authors.lastname: Guzei
authors.affiliation: Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States.
authors.forename: Samuel H
authors.initials: SH
authors.lastname: Gellman
mesh_terms: D006860:Hydrogen Bonding; D010455:Peptides / Q000737:chemistry*; D017433:Protein Structure, Secondary
chemical_list: D010455:Peptides