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Updated: Mar 14, 2026
14:44
Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
10.1K
Torsional and Electronic Factors Control the C-H⋅⋅⋅O Interaction
Russell W Driver1, Timothy D W Claridge1, Steve Scheiner2
1Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|October 7, 2016
Summary
Non-conventional hydrogen bonds, like C-H⋅⋅⋅O interactions, influence small molecule conformation due to favorable torsional and electronic effects. Deconvoluting these interactions in complex systems presents significant challenges for analysis.
Area of Science:
- Chemical Physics
- Molecular Biology
- Structural Chemistry
Background:
- The role of non-conventional hydrogen bonds, specifically C-H⋅⋅⋅O interactions, in small molecule conformation is not fully understood.
- Understanding these interactions is crucial for molecular design and predicting structural properties.
Purpose of the Study:
- To investigate the influence of C-H⋅⋅⋅O interactions on the conformation of β-turn mimetics.
- To elucidate the factors governing the population of states with conformationally significant C-H⋅⋅⋅O interactions.
Main Methods:
- Utilized X-ray crystallography and NMR spectroscopy to study molecular structures.
- Employed quantum chemical calculations to analyze electronic and torsional effects.
- Examined a series of β-turn mimetics to model peptide and protein environments.
Main Results:
- Favorable torsional and electronic effects were identified as key drivers for C-H⋅⋅⋅O interactions influencing conformation.
- Demonstrated the difficulty in isolating the contribution of a single noncovalent interaction amidst multiple interdependent factors.
- Highlighted the challenges in drawing unambiguous conclusions from NMR chemical shift data alone in complex molecular systems.
Conclusions:
- C-H⋅⋅⋅O interactions play a role in small molecule conformation, driven by specific energetic and structural factors.
- The interplay of various noncovalent interactions complicates the analysis of individual contributions.
- Further studies are needed to refine methods for deconvoluting complex intermolecular forces in molecular systems.
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