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Updated: Jul 18, 2025
In Vitro Directed Evolution of a Restriction Endonuclease with More Stringent Specificity
Published on: March 25, 2020
Double asymmetric synthesis: faster reactions are more selective and a model to estimate relative rate
Christopher J Richards1, O Stephen Ojo1
1School of Chemistry, University of East Anglia, Norwich, NR4 7TJ, UK. Chris.Richards@uea.ac.uk.
Abstract:
The catalysed reaction of an enantiopure substrate with formation of a new chirality element may result in higher diastereoselectivity with one enantiomer of a catalyst (matched pair) than with the other (mismatched pair). The hypothesis that the matched reaction is faster was investigated using literature examples of kinetic resolution procedures that result in the formation of a new stereogenic centre. With one exception from fifteen examples, the selectivity factor (s = kfast/kslow) = kmatched/kmismatched. A model to estimate the relative rate of a fast-matched reaction vs. the corresponding slow-mismatched reaction is proposed. This model also provides insight into the basis of the selectivity displayed in the kinetic resolution procedures studied.
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