Asymmetric Reduction of <i>β</i>-Keto Esters with an Enzyme from Bakers’ Yeast

Abstract

Abstract Various β-keto esters have been reduced by one of β-keto ester reductases isolated from bakers’ yeast. The corresponding β-hydroxy esters have been obtained in excellent enantiomeric and diastereomeric excesses, respectively. It has also been elucidated that the reductase recognizes the stereochemistry not only at the β-carbon but also at the α-carbon affording one of the four possible diastereoisomers of α-substituted β-hydroxy esters predominantly. The stereoselectivity is excellent and chemical yields are moderate to good.