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Updated: Jul 1, 2026

Unraveling Entropic Rate Acceleration Induced by Solvent Dynamics in Membrane Enzymes
Published on: January 16, 2016
Influence of the solvent description on the predicted mechanism of SN2 reactions
Monika Wujec1, Agata Siwek, Joanna Dzierzawska
1Department of Organic Chemistry, Faculty of Pharmacy, Medical University, Staszica 6, Lublin, Poland.
Abstract:
The influence of the implicit solvent model on transition state structures of two S N2 reactions of biochemical importance is presented. In the considered methyl transfer reaction, we show experimentally that the rate constant in blood serum is about 60% slower than in the aqueous solution and that the implicit solvent model with slightly modified parameters for water captures correctly the energetics of this reaction. With the example of the reaction between 4-methyl-1,2,4-triazol-3-thione and ethyl bromoacetate, we show that relative stabilities of the conformationally different transition states depend upon the solvent inclusion strategy.
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