Division of Pharmaceutical Sciences, Graduate School of Medical Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
Chemistry. 2013 Jun 24;19(26):8665-72. doi: 10.1002/chem.201300364. Epub 2013 May 6.
The total syntheses of four fawcettimine-related Lycopodium alkaloids, (±)-fawcettimine, (±)-fawcettidine, (±)-lycoposerramine-Q, and (±)-lycoflexine, were completed in a highly stereoselective manner. The Pauson-Khand reaction of 4-methylidene-6-siloxyoct-1-en-7-yne followed by regio- and stereoselective hydrogenation led to the short-step preparation of the bicyclo[4.3.0]nonenone intermediate bearing a methyl group with the required stereochemistry. The subsequent chemical manipulation of the bicyclic compound afforded the 6-5-9-membered tricyclic dioxo compound, which was then transformed into the four targeted alkaloids in an alternative and more efficient fashion.
四种法考明相关石松生物碱（±）-法考明、（±）-法考丁、（±）-lycoposerramine-Q 和（±）-lycoflexine 的全合成以高度立体选择性的方式完成。4-亚甲基-6-硅氧代辛-1-烯-7-炔的 Pauson-Khand 反应，然后进行区域和立体选择性加氢，可短步骤制备具有所需立体化学的带有甲基的双环[4.3.0]壬-1-烯酮中间体。随后对双环化合物进行化学操作，得到 6-5-9 元三环二氧杂化合物，然后以替代且更有效的方式转化为这四种目标生物碱。
