Department of Chemistry and Centre for Integrated Protein Science, Ludwig-Maximilians-Universität München, Butenandtstrasse 5-13, 81377 München (Germany) http://www.cup.uni-muenchen.de/oc/trauner/
Angew Chem Int Ed Engl. 2015 Apr 20;54(17):5079-83. doi: 10.1002/anie.201411350. Epub 2015 Apr 8.
A biomimetic total synthesis of santalin Y, a structurally complex but racemic natural product, is described. The key step is proposed to be a (3+2) cycloaddition of a benzylstyrene to a "vinylogous oxidopyrylium", which is followed by an intramolecular Friedel-Crafts reaction. This cascade generates the unique oxafenestrane framework of the target molecule and sets its five stereocenters in one operation. Our work provides rapid access to santalin Y and clarifies its biosynthetic relationship with other colorants isolated from red sandalwood.
本文描述了结构复杂但外消旋的天然产物 santalin Y 的仿生全合成。该反应的关键步骤被认为是苄基苯乙烯与“乙烯基氧化吡喃鎓”的（3+2）环加成，随后是分子内傅克反应。该级联反应生成了目标分子独特的氧杂菲烷骨架，并在一步反应中构建了其五个手性中心。我们的工作为 santalin Y 的快速合成提供了途径，并阐明了其与从紫檀属木材中分离出的其他着色剂的生物合成关系。
