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Updated: Jul 4, 2026
08:51
Coulomb Explosion Imaging as a Tool to Distinguish Between Stereoisomers
Published on: August 18, 2017
Odour character differences for enantiomers correlate with molecular flexibility
Jennifer C Brookes1, A P Horsfield, A M Stoneham
1Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK. ucapjcb@ucl.ac.uk
Journal of the Royal Society, Interface
|July 4, 2008
Summary
Molecular flexibility influences how enantiomers smell, with flexible six-membered ring enantiomers having distinct scents. This finding aids understanding olfactory receptor selectivity mechanisms.
Area of Science:
- Olfactory neuroscience
- Molecular recognition
- Chirality
Background:
- The olfactory system detects diverse molecules via nasal receptors, but receptor selectivity mechanisms remain debated.
- Enantiomers, chiral molecules existing as left- and right-handed pairs, are crucial for investigating these mechanisms.
Purpose of the Study:
- To investigate the correlation between molecular flexibility and the perceived scent differences between enantiomers.
- To evaluate proposed models of olfactory receptor selectivity.
Main Methods:
- Analysis of scent perception for various enantiomers, focusing on those with six-membered ring flexibility.
- Discussion of experimental uncertainties and comparison with existing receptor selectivity models.
Main Results:
- A correlation was identified between molecular flexibility and whether enantiomers possess the same scent.
- Enantiomers with six-membered ring flexibility consistently exhibit different odors.
- Experimental uncertainties were acknowledged and discussed.
Conclusions:
- Molecular flexibility, particularly in six-membered ring systems, plays a significant role in olfactory discrimination of enantiomers.
- Findings support generalized 'swipe card' models where shape is necessary but not solely sufficient for receptor activation, with other factors like vibrational frequencies or electronic properties being critical.
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