Stereoselective Bioreduction of Heptan-2-one and Octan-2-one Catalyzed by Petroselinum Crispum Cells

Abstract

The possibility of biotransformation of prochiral heptan-2-one and octan-2-one to enantiomerically pure (2S)-(+)-heptan-2-ol and (2S)-(+)-octan-2-ol using P. crispum cells has been studied, and conditions have been selected to synthesize (2S)-(+)-heptan-2-ol in a high yield of 99% with an enantiomeric excess of 98% ee within 24 h. Transformation of octan-2-one within 72 h gives the corresponding alcohol in 67% yield (74% ee). Conditions for bioreduction of octan-2-one in the presence of various exogenous reducing agents—ethanol (1–5%), isopropanol (1–5%), or glucose (equimolar amount)—have been optimized. The maximum yield and optical purity of (S)-(+)-octan-2-ol, 78% (93% ee), is achieved in 48 h in the presence of 3% ethanol. Reduction of octan-2-one in the presence of isopropanol (1–5%) or an equimolar amount of glucose leads to some increase in the yield and/or optical purity of (2S)-octan-2-ol in comparison with biotransformation in the absence of an exogenous reducing agent.