Screening and Application of Microbial Esterases for the Enantioselective Synthesis of Chiral Glycerol Derivatives

A number of enzymes with reasonable to excellent selectivities for the conversion of prochiral 2-benzylglyceroldiacetate 1c into optically active monoacetate 2c could be identified in a screening of microbial esterases and lipases. For the synthesis of the S-enantiomer of 2c by hydrolysis, two enzymes (from Aspergillus fumigatus and from Mucor javanicus) were identified which give the product with an e.e.-value of 75%. The R-enantiomer can be obtained with a purified lipase/esterase from Pseudomonas fluorescens in 96% e.e. The optical purity of the product was determined without derivatisation by chromatography on a chiral HPLC-column.