Sulfur-containing chiral heterocyclic secondary alcohols are relevant intermediates in the preparation of enantiomerically pure compounds endowed with biological activity. In this report, we evaluated the reductive potential of different lactic acid bacteria as whole-cell biocatalysts of the enantioselective reduction of 1-(thiophen-2-yl)ethanone (1). Enterococcus faecium BY48, isolated from boza, a cereal-based fermented beverage, was found to be the best biocatalyst in our initial investigations. Using whole-cell preparations of E. faecium BY48, we then systematically analyzed the reaction parameters (pH, incubation period, agitation speed, and temperature) to optimize the yield, the enantiomeric excess (e. e.), and the conversion leading to (S)-1-(thiophen-2-yl)ethanol [(S)-2]. The target derivative, which is a precursor in the synthesis of biologically active chiral compounds, was obtained in enantiomerically pure form, gram-scale amounts, and high yield. This is also the first report that the manufacture of (S)-2 in excellent conversion, yield, enantiopure form, and gram scale used whole-cell biocatalyst. This whole-cell E. faecium BY48 biocatalyzed reaction is a clean, environmentally friendly, and cost-effective process, representing a valuable alternative to chemical catalysis or previously reported biocatalytic procedures in the preparation of (S)-2.

中文翻译：

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粪肠球菌 BY48 生物催化剂下高对映体纯度的 (S)-1-(噻吩-2-基) 乙醇的革兰氏规模合成

含硫手性杂环仲醇是制备具有生物活性的对映体纯化合物的相关中间体。在本报告中，我们评估了不同乳酸菌作为对映选择性还原 1-(thiophen-2-yl)ethanone ( 1 ) 的全细胞生物催化剂的还原潜力。从谷类发酵饮料 boza 中分离出的粪肠球菌BY48 在我们的初步研究中被发现是最好的生物催化剂。使用粪肠球菌BY48的全细胞制剂，我们系统地分析了反应参数（pH、孵育时间、搅拌速度和温度）以优化产率、对映体过量 (ee) 和导致 ( S)-1-(噻吩-2-基)乙醇[ ( S )-2 ]。目标衍生物是生物活性手性化合物合成的前体，以对映体纯形式、克级量和高产率获得。这也是第一个使用全细胞生物催化剂制造( S )-2的报告，该产品具有出色的转化率、产率、对映体纯形式和克级规模。这种全细胞粪肠球菌BY48 生物催化反应是一种清洁、环保且具有成本效益的过程，代表了一种有价值的替代化学催化或先前报道的( S )-2制备中的生物催化程序的方法。