Chiral sulfoxides are widely used in organic synthesis as chiral auxiliaries. There are numerous strategies for the preparation of enantiomerically pure sulfoxides, based either on the enantioselective oxidation of sulphides or the enantiospecific reduction of sulfoxides. For both cases, bioconversion techniques have been developed and proposed for large-scale synthesis. Methionine sulfoxide reductase enzymes (MsrA and MsrB) catalyse the stereoselective conversion of methionine sulfoxide to methionine. MsrA can also catalyse the reduction of other exogenous sulfoxides, including p-tolyl methyl sulfoxide. However, the stereoselectivity towards this type of substrate is not yet well characterized. The activity and enantioselectivity of MsrA toward several aryl methyl sulfoxides is presented in this paper.

手性亚砜广泛用作手性助剂在有机合成中。基于硫化物的对映选择性氧化或亚砜的对映特异性还原，有许多制备对映体纯亚砜的策略。对于这两种情况，已经开发并提出了用于大规模合成的生物转化技术。甲硫氨酸亚砜还原酶（MsrA和MsrB）催化甲硫氨酸亚砜向甲硫氨酸的立体选择性转化。MsrA还可以催化其他外源亚砜的还原，包括对甲苯基甲基亚砜。但是，对这种类型的底物的立体选择性尚未很好地表征。本文介绍了MsrA对几种芳基甲基亚砜的活性和对映选择性。