Asymmetric reduction of ethyl 2-methyl 3-oxobutanoate by Chlorella.

T Kuramoto, K Iwamoto, M Izumi, M Kirihata, F Yoshizako

Index: Biosci. Biotechnol. Biochem. 63(3) , 598-601, (1999)

Full Text: HTML

Abstract

Chlorella pyrenoidosa Chick reduced ethyl 2-methyl 3-oxobutanoate to the corresponding alcohols with the diastereomer (anti/syn) ratio of 53/47. The enantiomer excesses of anti-(2S, 3S)- and syn-(2S, 3R)-hydroxy esters were 89 and > 99ee% respectively. C. vulgaris and C. regularis afforded predominantly the syn-isomer, contrary to C. pyrenoidosa. The differences in the activity of reducing ethyl 2-methyl 3-oxobutanoate were observed among three strains of Chlorella. Addition of 2% metal salts slightly increased the chemical yield of the hydroxy ester.