ACIB GmbH c/o, Biocatalytic Synthesis, University of Graz, Heinrichstrasse 28, 8010-Graz, Austria.
Chemistry. 2012 Aug 13;18(33):10362-7. doi: 10.1002/chem.201200990. Epub 2012 Jun 26.
The degree of C=C bond activation in the asymmetric bioreduction of α,β-unsaturated carboxylic esters by ene-reductases was studied, and general recommendations to render these "borderline-substrates" more reactive towards enzymatic reduction are proposed. The concept of "supported substrate activation" was developed. In general, an additional α-halogenated substituent proved to be beneficial for enzymatic activity, whereas β-alkyl or β-aryl substituents were detrimental for the reactivity of nonhalogenated substrates, and α-cyano groups showed little effect. The alcohol moiety of the ester functionality was found to have a strong influence on the reaction rate. Overall, activities were determined by both steric and electronic effects.
烯还原酶对α,β-不饱和羧酸酯的不对称生物还原中 C=C 键的活化程度进行了研究，并提出了使这些“边界底物”更具反应性的一般性建议。提出了“受支撑的底物活化”的概念。一般来说，额外的α-卤代取代基有利于酶活性，而β-烷基或β-芳基取代基不利于非卤代底物的反应性，而α-氰基基团的影响较小。酯官能团的醇部分对反应速率有很强的影响。总的来说，活性受到空间和电子效应的共同影响。
