Department of Organic Synthesis and Process Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad 500007, India.
Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh 201002, India.
J Org Chem. 2020 Oct 2;85(19):12418-12429. doi: 10.1021/acs.joc.0c01644. Epub 2020 Sep 14.
The first asymmetric total syntheses of the real isolation product (2,5,8)-greensporone F and (2,5,8)-dechlorogreensporone F, 14-membered resorcylic acid lactones with a -2,5-disubstituted tetrahydrofuran ring system, was accomplished. The synthesis features a late-stage Lewis acid-catalyzed stereoselective intramolecular oxa-Michael reaction, -selective ring-closing metathesis, De Brabander's esterification, and Jacobsen's hydrolytic kinetic resolution as the key steps. Synthesis of both real isolation and erroneously proposed structure necessitated the revision of the absolute configuration of greensporone F and dechlorogreensporone F. The erroneous representation of (2,5,8)-configuration in greensporone F and dechlorogreensporone F was assigned to be (2,5,8) by comparison with the NMR data and specific rotation of the synthetic compounds with that of the reported data.
首次完成了具有 -2,5-二取代四氢呋喃环系的 14 元重排树脂酸内酯（2,5,8）-greensporone F 和（2,5,8）-去氯 greensporone F 的真实分离产物的不对称全合成。该合成的关键步骤包括晚期路易斯酸催化的立体选择性分子内氧杂-Michael 反应、 -选择性环 closing metathesis、De Brabander 的酯化和 Jacobsen 的水解动力学拆分。由于需要对 greensporone F 和去氯 greensporone F 的绝对构型进行修订，因此有必要对其实验分离和错误提出的结构进行合成。通过与 NMR 数据和与报道数据的合成化合物的比旋光度比较，将 greensporone F 和去氯 greensporone F 中（2,5,8）-构型的错误表示指定为（2,5,8）。
