Biocatalytic Asymmetric Reduction of γ‐Keto Esters to Access Optically Active γ‐Aryl‐γ‐butyrolactones
作者:Paweł Borowiecki、Natalia Telatycka、Mateusz Tataruch、Anna Żądło‐Dobrowolska、Tamara Reiter、Karola Schühle、Johann Heider、Maciej Szaleniec、Wolfgang Kroutil
DOI:10.1002/adsc.201901483
日期:2020.5.12
achieved by enzymatic asymmetric reduction of the corresponding sterically demanding γ‐keto esters employing wild‐type and recombinant alcohol dehydrogenases. The best stereoselectivities for the reduction via hydrogen transfer was obtained with two short chain dehydrogenases (SDRs) of complementary stereospecificity from Aromatoleum aromaticum, namely the Prelog‐specific NADH‐dependent (S)‐1‐phenylethanol
通过使用野生型和重组醇脱氢酶酶促不对称还原相应的空间需求型γ-酮酯,可以实现一系列功能化的光学活性γ-芳基-γ-丁内酯的高效立体选择性合成。通过芳香香气中两个互补的立体特异性短链脱氢酶(SDR)获得了通过氢转移还原的最佳立体选择性,即Prelog特异性NADH依赖性(S)-1-苯乙醇脱氢酶[(S)-PED]和抗Prelog特异性(R)-1-(4-羟苯基)乙醇脱氢酶[(R)-HPED]。两种酶催化的生物转化,然后由TFA催化的所得γ-羟基酯环化,分别为(S)和(R)构型的产品提供了极佳的光学纯度(ee高达99%以上)。合成值已在制备规模上证明,用于模型化合物4-氧代-4-苯基丁酸甲酯的不对称生物还原,在67-74中可提供光学纯的(S)-γ-苯基-γ-丁内酯(> 99%ee)在89–95%的转化率下,分离出的收率%,取决于所应用的规模。