Asymmetric reduction of α-keto esters and α-diketones with a bakers' yeast keto ester reductase

Article abstract of DOI:10.1246/bcsj.72.99

Optically pure α-hydroxy esters and α-hydroxy ketones have been synthesized by the reduction of the corresponding ketones with a keto ester reductase isolated from bakers' yeast (YKER-I). The reduction of α-keto esters affords the corresponding (S)- or (R)-hydroxy esters selectively, where the stereochemical course depends on the chain length of the alkyl substituent on the carbonyl group. An α-keto short alkanoic ester affords the corresponding (S)-hydroxy ester, whereas a long alkanoate yields the corresponding (R)-hydroxy ester. The reduction of α-diketones affords the corresponding (S)-2-hydroxy ketones regio- and stereoselectively.