Abstract
In this study the formation of the lactyl–thiamin diphosphate intermediate (L–ThDP) is addressed using density functional theory calculations at X3LYP/6-31++G(d,p) level of theory. The study includes potential energy surface scans, transition state search, and intrinsic reaction coordinate calculations. Reactivity is analyzed in terms of Fukui functions. The results allow to conclude that the reaction leading to the formation of L–ThDP occurs via a concerted mechanism, and during the nucleophilic attack on the pyruvate molecule, the ylide is in its AP form. The calculated activation barrier for the reaction is 19.2 kcal/mol, in agreement with the experimental reported value.












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The authors gratefully acknowledge financial support from Fondecyt, Grant No. 1100064.
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Alvarado, O., Jaña, G. & Delgado, E.J. Computer-assisted study on the reaction between pyruvate and ylide in the pathway leading to lactyl–ThDP. J Comput Aided Mol Des 26, 977–982 (2012). https://doi.org/10.1007/s10822-012-9589-3
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DOI: https://doi.org/10.1007/s10822-012-9589-3