A Synthesis of Alstonlarsine A via Alstolucines B and F Demonstrates the Chemical Feasibility of a Proposed Biogenesis
A Synthesis of Alstonlarsine A via Alstolucines B and F Demonstrates the Chemical Feasibility of a Proposed Biogenesis
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通过 Alstolucines-B 和 F 合成 Alstonlarsine A 证明了所提出的生物发生的化学可行性
DOI：
10.1002/anie.202215098
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发表时间：
2022
期刊：
影响因子：
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通讯作者：
Vanderwal, Christopher D.
中科院分区：
文献类型：
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作者：
Barnes, Griffin L.;Hong, Allen Y.;Vanderwal, Christopher D.
我们通过对马钱子生物碱 alstolucines B 和 F 的重排，为复杂生物碱 alstolucines A 的起源提供了一个新的生物遗传学建议。此外，我们提供了该建议的化学可行性证据，即通过短而有效的 N-甲基化、β-消除和级联序列，将合成的 alstolucines 轻松转化为 alstonlarsine A 1,7-氢化物移位/曼尼希环化。我们相信，这是第一个涉及“叔氨基效应”的生物遗传学提议，“叔氨基效应”是曼尼希环化的基于氢化物移位的内部氧化还原触发器。级联的另一个有趣的特征是，其立体化学结果很可能源于氢化物转变期间的构象偏好。
We offer a new biogenetic proposal for the origin of the complex alkaloid alstonlarsine A, through rearrangement of theStrychnosalkaloids alstolucines B and F. Further, we provide evidence of the chemical feasibility of this proposal in the facile conversion of synthetic alstolucines into alstonlarsine A through a short, efficient sequence ofN‐methylation, β‐elimination, and a cascade 1,7‐hydride shift/Mannich cyclization. We believe that this is the first biogenetic proposal involving the “tert‐amino effect”, a hydride‐shift‐based internal redox trigger of a Mannich cyclization. A further interesting feature of the cascade is that its stereochemical outcome most likely originates in conformational preferences during the hydride shift.