Non‐classical Helices with <i>cis</i> Carbon–Carbon Double Bonds in the Backbone: Structural Features of α,γ‐Hybrid Peptide Foldamers

Mothukuri Ganesh Kumar; Varsha J. Thombare; Mona M. Katariya; Kuruva Veeresh; K. Muruga Poopathi Raja; Hosahudya N. Gopi

doi:10.1002/ange.201602861

Zuschrift
Non‐classical Helices with cis Carbon–Carbon Double Bonds in the Backbone: Structural Features of α,γ‐Hybrid Peptide Foldamers

Mothukuri Ganesh Kumar, Varsha J. Thombare, Mona M. Katariya, Kuruva Veeresh, K. Muruga Poopathi Raja, Hosahudya N. Gopi

Source

Angewandte Chemie > 128 > 27 > 7978 - 7982

The impact of geometrically constrained cis α,β‐unsaturated γ‐amino acids on the folding of α,γ‐hybrid peptides was investigated. Structure analysis in single crystals and in solution revealed that the cis carbon–carbon double bonds can be accommodated into the 12‐helix without deviation from the overall helical conformation. The helical structures are stabilized by 4→1 hydrogen bonding in a similar manner to the 12‐helices of β‐peptides and the 3₁₀ helices of α‐peptides. These results show that functional cis carbon–carbon double bonds can be accommodated into the backbone of helical peptides.

Helikal wie echte Peptide: Hybridhelices mit cis‐konfigurierten Kohlenstoff‐Kohlenstoff‐Doppelbindungen im Rückgrat wurden synthetisiert und ihre Konformationen in Lösung und im Einkristall bestimmt. Dabei stellte sich heraus, dass die cis‐Doppelbindungen die insgesamte helikale Faltung nicht beeinträchtigen.