Stereoselective, biocatalytic reductions of alpha-chloro-beta-keto esters
Iwona A Kaluzna1, Brent D Feske, Weerawut Wittayanan
1Department of Chemistry, University of Florida, Gainesville, Florida 32611, USA.
Abstract:
Eighteen known and putative reductases from baker's yeast (Saccharomyces cerevisiae) were tested for the ability to reduce a series of alpha-chloro-beta-keto esters. In nearly all cases, it was possible to produce at least two of the four possible alpha-chloro-beta-hydroxy ester diastereomers with high optical purities. The utility of this approach was demonstrated by reducing ethyl 2-chloroacetoacetate to the corresponding syn-(2R,3S)-alcohol on a multigram scale using whole cells of an Escherichia coli strain overexpressing a single yeast reductase identified from the screening studies.
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