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Updated: Jun 7, 2026

Synthesis of Esters Via a Greener Steglich Esterification in Acetonitrile
Published on: October 30, 2018
A review-biosynthesis of optically pure ethyl (S)-4-chloro-3-hydroxybutanoate ester: recent advances and future
Qi Ye1, Pingkai Ouyang, Hanjie Ying
1State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing, People's Republic of China.
Abstract:
Ethyl (S)-4-chloro-3-hydroxybutanoate ester ((S)-CHBE) is a precursor of enantiopure intermediates used for the production of chiral drugs, including the cholesterol-lowering 3-hydroxy-3-methyl-glutaryl CoA reductase inhibitors (statins). The asymmetric reduction of ethyl 4-chloro-3-oxobutanoate ester (COBE) to (S)-CHBE by biocatalysis has several positive attributes, including low cost, mild reaction conditions, high yield, and a high level of enantioselectivity. During genome database mining of the yeast Pichia stipitis, our group found two novel carbonyl reductases (PsCRI and PsCRII) that have a promising future for the industrial production of (S)-CHBE with >99% enantiomeric excess. This review covers the main process of biosynthesis of (S)-CHBE: screening of microorganisms that catalyze the reduction of COBE to (S)-CHBE (I); gene cloning, expression, and characterization of carbonyl reductases for the production of (S)-CHBE in Escherichia coli (II); development of cofactor generation systems for regenerating cofactors (III); and biocatalysis of COBE to (S)-CHBE by recombinant E. coli (IV).
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