Total Synthesis of (+)-Lyconadin A and Related Compounds via Oxidative C−N Bond Formation
作者:Scott P. West、Alakesh Bisai、Andrew D. Lim、Raja R. Narayan、Richmond Sarpong
DOI:10.1021/ja903868n
日期:2009.8.12
fundamental bond construction in organic synthesis and is indispensable for the synthesis of alkaloid natural products. In the context of the synthesis of the architecturally complex Lycopodium alkaloid lyconadin A, we have discovered a highly efficient oxidative C-N bond forming reaction that relies on the union of a nitrogen anion and a carbon anion. Empirical evidence amassed during our synthetic studies
碳氮(CN)键的形成是有机合成中的基本键结构,是合成生物碱天然产物必不可少的。在合成结构复杂的石松生物碱 lyconadin A 的背景下,我们发现了一种高效的氧化 CN 键形成反应,该反应依赖于氮阴离子和碳阴离子的结合。在我们的合成研究中积累的经验证据表明,CN 键形成过程的机制包括极性过程和自由基过程。在此,我们介绍了我们对这种新型 CN 键形成反应的研究及其在 lyconadin A 和相关衍生物的对映选择性全合成中的应用。
Unified Strategy for the Synthesis of the “Miscellaneous” <i>Lycopodium</i> Alkaloids: Total Synthesis of (±)-Lyconadin A
作者:Alakesh Bisai、Scott P. West、Richmond Sarpong
DOI:10.1021/ja8028069
日期:2008.6.1
Total synthesis of the Lycopodium alkaloid lyconadin A was achieved in 18 steps starting from a readily available vinylogous ester and bromopicoline. The key step in the total synthesis is a proximity-driven oxidative C-N bond-forming reaction that yields the lyconadin pentacycle from a tetracyclic precursor. The key tetracycle, which has been prepared for the first time, is a versatile intermediate
石松生物碱 lyconadin A 的全合成是从容易获得的乙烯酯和溴甲基吡啶开始的 18 个步骤中实现的。全合成的关键步骤是邻近驱动的氧化 CN 键形成反应,该反应从四环前体产生lyconadin 五环。首次制备的关键四环是一种多功能中间体,可用于多种石松生物碱的全合成。该计划成功的关键是有效制备吡啶环化的环庚二烯三环,它有望成为获取各种含有天然产物的七元环的通用策略。