In recent years, the reductive amination of ketones in the presence of amine dehydrogenases emerged as an attractive synthetic strategy for the enantioselective preparation of amines starting from ketones, an ammonia source, a reducing reagent and a cofactor, which is recycled in situ by means of a second enzyme. Current challenges in this field consists of providing a broad synthetic platform as well as process development including enzyme immobilization. In this contribution these issues are addressed. Utilizing the amine dehydrogenase EsLeuDH-DM as a mutant of the leucine dehydrogenase from Exigobacterium sibiricum, a range of aryl-substituted ketones were tested as substrates revealing a broad substrate tolerance. Kinetics as well as inhibition effects were also studied and the suitability of this method for synthetic purpose was demonstrated with acetophenone as a model substrate. Even at an elevated substrate concentration of 50 mM, excellent conversion was achieved. In addition, the impact of water-miscible co-solvents was examined, and good activities were found when using DMSO of up to 30% (v/v). Furthermore, a successful immobilization of the EsLeuDH-DM was demonstrated utilizing a hydrophobic support and a support for covalent binding, respectively, as a carrier.

近年来，在胺脱氢酶的存在下对酮的还原胺化作为从苯酮，氨源，还原剂和辅因子开始的胺的对映选择性制备胺的有吸引力的合成策略出现，该方法通过原位再循环。第二种酶。该领域当前的挑战包括提供广泛的合成平台以及包括酶固定化在内的工艺开发。在此贡献中，解决了这些问题。利用胺脱氢酶EsLeuDH-DM作为西伯利亚杆菌（Exigobacterium sibiricum）亮氨酸脱氢酶的突变体，测试了一系列芳基取代的酮作为底物，显示出较宽的底物耐受性。还研究了动力学以及抑制作用，并以苯乙酮为模型底物证明了该方法对合成目的的适用性。即使在提高的底物浓度为50 mM的情况下，也可以实现出色的转化率。另外，检查了与水混溶的助溶剂的影响，使用高达30％（v / v）的DMSO时发现了良好的活性。此外，利用疏水性支持物和用于共价结合的支持物分别作为载体，证明了EsLeuDH-DM的成功固定。