Laboratory of Synthesis and Natural Products, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, EPFL-SB-ISIC-LSPN, BCH 5304, 1015, Lausanne, Switzerland.
Angew Chem Int Ed Engl. 2020 Nov 16;59(47):21195-21202. doi: 10.1002/anie.202007548. Epub 2020 Sep 11.
The development of concise, sustainable, and cost-effective synthesis of aryltetralin lignans, bearing either a fused lactone or cyclic ether, is of significant medicinal importance. Reported is that in the presence of Fukuzumi's acridinium salt under blue LED irradiation, functionalized dicinnamyl ether derivatives are converted into aryltetralin cyclic ether lignans with concurrent generation of three stereocenters in good to high yields with up to 20:1 diastereoselectivity. Oxidation of an alkene to the radical cation is key to the success of this formal Diels-Alder reaction of electronically mismatched diene and dienophile. Applying this methodology, six natural products, aglacin B, aglacin C, sulabiroin A, sulabiroin B, gaultherin C, and isoshonanin, are synthesized in only two to three steps from readily available biomass-derived monolignols. A revised structure is proposed for gaultherin C.
简洁、可持续且具有成本效益的芳基四氢呋喃木脂素合成方法的发展具有重要的医学意义，这些木脂素带有融合内酯或环醚。据报道，在 Fukuzumi 的吖啶鎓盐存在下，在蓝色 LED 照射下，功能化二肉桂醚衍生物转化为芳基四氢呋喃环醚木脂素，同时在良好至高产率下生成三个立体中心，非对映选择性高达 20:1。烯烃氧化为自由基阳离子是该电子不匹配二烯和亲二烯体的形式 Diels-Alder 反应成功的关键。应用该方法，从易得的生物质衍生的单体酚出发，仅通过两步至三步即可合成 6 种天然产物：aglacin B、aglacin C、sulabiroin A、sulabiroin B、gaultherin C 和异厚朴酚。对 gaultherin C 的结构进行了修订。
