Enantioselective Hydrolysis of Glycidyl Methylphenyl Ethers by Botryosphaeria Dothidea ZJUZQ007: Effect of Substitution Pattern on Enantioselectivity

Bioresolution of (R)-glycidyl azide by Aspergillus niger ZJUTZQ208: a new and concise synthon for chiral vicinal amino alcohols

A newly isolated Aspergillus niger strain containing epoxide hydrolase was used to resolve racemic glycidyl azide and four derivatives to the (R)-enantiomers. After optimization of the biotransformation conditions, (R)-glycidyl azide was produced with good enantioselectivity (e.e.s > 95 %, E > 20). The substrate structure, pH, and reaction time were found to have profound influences on the catalytic property of A. niger ZJUTZQ208. Enantiopure glycidyl azide was further utilized to synthesize linezolid in good yield, indicating it is a new and concise synthon for chiral vicinal amino alcohols. Enzyme-substrate docking studies were carried out with glycidyl azide to study the selectivity of this strain.

Efficient asymmetric hydrolysis of styrene oxide catalyzed by Mung bean epoxide hydrolases in ionic liquid-based biphasic systems

The asymmetric hydrolysis of styrene oxide to (R)-1-phenyl-1,2-ethanediol using Mung bean epoxide hydrolases was, for the first time, successfully conducted in an ionic liquid (IL)-containing biphasic system. Compared to aqueous monophasic system, IL-based biphasic systems could not only dissolve the substrate, but also effectively inhibit the non-enzymatic hydrolysis, and therefore markedly improve the reaction efficiency. Of all the tested ILs, the best results were observed in the biphasic system containing C(4)MIM·PF(6), which exhibited good biocompatibility with the enzyme and was an excellent solvent for the substrate. In the C(4)MIM·PF(6)/buffer biphasic system, it was found that the optimal volume ratio of IL to buffer, reaction temperature, buffer pH and substrate concentration were 1/6, 35°C, 6.5 and 100 mM, respectively, under which the initial reaction rate, the yield and the product e.e. were 18.4 mM/h, 49.4% and 97.0%. The biocatalytic process was shown to be feasible on a 500-mL preparative scale.