完成了石松生物碱 lyconadin A 的全合成,并将其应用于相关同源物 lyconadins B 和 C 的全合成。由于前所未有的五环骨架,Lyconadin A 作为全合成的一个具有挑战性的目标而受到关注。我们合成 lyconadin A 的特点是通过 aza-Prins 反应和电环开环的组合轻松构建高度稠合的四环骨架,然后形成 CN 键。广泛研究了四环的溴烯烃部分向关键烯酮中间体的转化,并建立了通过硫化物、肟或叠氮化物中间体的三种方法。由关键烯酮中间体构建吡啶酮环以完成lyconadin A的合成。
The Lyconadins: Enantioselective Total Syntheses of (+)-Lyconadin A and (−)-Lyconadin B
作者:Douglas C. Beshore、Amos B. Smith
DOI:10.1021/ja804939r
日期:2008.10.15
(+)-lyconadin A (1) and (-)-lyconadin B (2) is presented. Central to this venture was recognition and deployment of a key strategy-level intramolecular aldol/conjugate addition cascade that led, in a single operation, to two new carbon-carbon sigma-bonds, three new stereogenic centers, and two new rings, albeit with the incorrect stereogenicity at C(12) for the lyconadins. Correction of the C(12) stereogenicity
全面介绍了 (+)-lyconadin A (1) 和 (-)-lyconadin B (2) 的对映选择性全合成。该项目的核心是识别和部署一个关键的战略级分子内醛醇/共轭加成级联,在一次操作中,导致了两个新的碳碳 sigma 键、三个新的立体中心和两个新环,尽管lyconadins 在 C(12) 处的不正确立体性。C(12) 立体性的校正是通过质子化分子内胺的创新使用实现的。氨基碘烯烃环化结合 α-吡啶酮和 3,4-二氢吡啶酮环化方案,分别允许完成 (+)-lyconadin A (1) 和 (-)-lyconadin B (2) 的合成。
Lyconadins C and F, new Lycopodium alkaloids from Lycopodium complanatum
Lycopodium alkaloids. Biogenetically, lyconadins C (1) and F (2) might be related to lyconadins A (4) and B (5). The structures and relative stereochemistry of 1 and 2 were elucidated on the basis of spectroscopic data. The absolute stereochemistry of 2 was elucidated by chemical correlations with lyconadin B (5) through hemiaminal form of lyconadin F (3).
Total Syntheses of (+)-Lyconadin A and (−)-Lyconadin B
作者:Douglas C. Beshore、Amos B. Smith
DOI:10.1021/ja070336+
日期:2007.4.1
The enantioselective syntheses of (+)-lyconadin A and (-)-lyconadin B are described. Key bond constructions include a strategy-level intramolecular aldol/conjugate addition cascade, an olefin aminoiodination, and a novel one-pot alpha-pyridinone annulation.
A Unified Strategy for the Synthesis of 7-Membered-Ring-Containing<i>Lycopodium</i>Alkaloids
作者:Amy S. Lee、Brian B. Liau、Matthew D. Shair
DOI:10.1021/ja507740u
日期:2014.9.24
sequence for constructing the common 7-membered-ring core system, followed by either a biomimetic transannular Mannich reaction to access himeradine A (1), lycopecurine (3), and dehydrolycopecurine (4) or an imine reduction for lyconadins A (5) and B (6). This strategy may potentially enable access to all 7-membered-ring-containing Lycopodium alkaloids and provides additional insight into their biosynthetic
石松生物碱天然产物的一个独特子集共享一个 7 元环亚结构,可能来自一个常见的生物合成前体。为了探索和利用这些结构关系,我们寻求开发一种统一的生物合成启发策略,通过使用级联序列有效地获取这些复杂的多环生物碱。为了实现这些目标,(+)-fastigiatine (2) 的首次全合成是通过一系列级联反应完成的;我们在此全面介绍了我们的努力。这些努力的洞察导致了我们合成策略的关键修改,这使得 (-)-himeradine A (1)、(-)-lycopecurine (3) 和 (-)-dehydrolycopecurine (4) 的首次全合成成为可能,如以及 (+)-lyconadin A (5) 和 (-)-lyconadin B (6) 的合成。我们的方法具有非对映选择性的一锅序列,用于构建常见的 7 元环核心系统,然后是仿生跨环曼尼希反应以获取海美拉丁 A (1)、番茄红素 (3) 和脱氢番茄红素
Total Syntheses of Lyconadins A–C
作者:Takuya Nishimura、Aditya K. Unni、Satoshi Yokoshima、Tohru Fukuyama
DOI:10.1021/ja312065m
日期:2013.2.27
The total synthesis of the Lycopodium alkaloid lyconadin A was accomplished and it was applied to the totalsyntheses of the related congeners, lyconadins B and C. Lyconadin A has attracted attention as a challenging target for total synthesis due to the unprecedented pentacyclic skeleton. Our synthesis of lyconadin A features a facile construction of the highly fused tetracyclic skeleton through a
完成了石松生物碱 lyconadin A 的全合成,并将其应用于相关同源物 lyconadins B 和 C 的全合成。由于前所未有的五环骨架,Lyconadin A 作为全合成的一个具有挑战性的目标而受到关注。我们合成 lyconadin A 的特点是通过 aza-Prins 反应和电环开环的组合轻松构建高度稠合的四环骨架,然后形成 CN 键。广泛研究了四环的溴烯烃部分向关键烯酮中间体的转化,并建立了通过硫化物、肟或叠氮化物中间体的三种方法。由关键烯酮中间体构建吡啶酮环以完成lyconadin A的合成。