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Updated: Jul 5, 2026

Magnetic Tweezers for the Measurement of Twist and Torque
Published on: May 19, 2014
A highly stable short alpha-helix constrained by a main-chain hydrogen-bond surrogate
Ross N Chapman1, Gianluca Dimartino, Paramjit S Arora
1Department of Chemistry, New York University, New York, New York 10003, USA.
Abstract:
Herein we describe a strategy for the preparation of artificial alpha-helices involving replacement of one of the main-chain hydrogen bonds with a covalent linkage. To mimic the C=O...H-N hydrogen bond as closely as possible, we envisioned a covalent bond of the type C=X-Y-N, where X and Y are two carbon atoms connected through an olefin metathesis reaction. Our results demonstrate that the replacement of a hydrogen bond between the i and i + 4 residues at the N-terminus of a short peptide with a carbon-carbon bond results in a highly stable constrained alpha-helix at physiological conditions as indicated by CD and NMR spectroscopies. The advantage of this strategy is that it allows access to short alpha-helices with strict preservation of molecular recognition surfaces required for biomolecular interactions.
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