3‐Hydroxyglutarate and β,γ‐Epoxy Esters as Substrates for Pig Liver Esterase (PLE) and α‐Chymotrypsin

The pH dependence of the α‐chymotrypsin‐catalyzed hydrolysis of dimethyl 3‐hydroxyglutarate ( 3 ) has been studied. The e.e. was determined by HPLC analysis of diastereoisomeric camphanoic‐acid derivatives. Kinetic resolution of the β,α‐epoxy esters 10 and 24 by pig liver esterase has been shown to provide an alternative access to chiral β‐hydroxy esters and acids of high optical purity. By this latter method, the unnatural enantiomer of γ‐amino‐β‐hydroxybutyric acid (GABOB) has been synthesized. Finally, dimethyl meso ‐3,4‐epoxyadipate ( 19 ) was hydrolyzed by pig liver esterase with almost 100% selectivity.