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Heterogeneous H-bonding in a foldamer helix.

ABSTRACT: Structural characterization of new ?/?-peptide foldamers containing the cyclically constrained ?-amino acid I is described. Crystallographic and 2D NMR analysis shows that ? residue I promotes the formation of a 12/10-helical secondary structure in ?/?-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.

SUBMITTER: Fisher BF

PROVIDER: S-EPMC4687740 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Heterogeneous H-bonding in a foldamer helix.

Fisher Brian F BF Guo Li L Dolinar Brian S BS Guzei Ilia A IA Gellman Samuel H SH

Journal of the American Chemical Society 20150514 20

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 distinc ...[more]

PMID: 25974390

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