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在Heronamide A的生物合成中进行跨环 [6 + 4] 和双模环添加
Peiyuan Yu1, Ashay Patel1, K N Houk1
1Department of Chemistry and Biochemistry, ‡Department of Chemical and Biomolecular Engineering, University of California , Los Angeles, California 90095, United States.
Journal of the American Chemical Society
|October 6, 2015
概括
密度函数理论建模支持在胺A生物合成中提出的跨环 [6 + 4] 循环添加. 这种反应是立体选择性的,产生稳定的 [6 + 4] 附加物,而不是 [4 + 2] 附加物.
科学领域:
- 有机化学
- 计算化学
- 生物化学
背景情况:
- 赫罗纳胺A生物合成涉及一个拟议的跨环 [6 + 4] 循环添加.
- 了解这一关键步骤对于阐明自然产品的形成至关重要.
研究的目的:
- 模拟和验证在胺甲生物合成中的拟议的跨环 [6 + 4] 循环添加.
- 研究反应途径的立体选择性和热力学稳定性.
主要方法:
- 使用密度函数理论 (DFT) 的计算.
- 进行了反应机制,过渡状态和 adduct 稳定性的分析.
主要成果:
- 拟议的 [6 + 4] 循环添加具有高度刻板选择性,产生单个主要产品.
- 一个双通道过渡状态导致了 [6 + 4] 和 [4 + 2] 引证.
- 在热力学上, [6 + 4] 附加物比 [4 + 2] 附加物优于 5.2 kcal mol ((-1).
- 通过Cope重排,可以在 [6 + 4] 和 [4 + 2] 引数之间进行相互转换.
结论:
- 计算结果强烈支持在heronamide A生物发生过程中跨环 [6 + 4] 循环添加的可信性.
- 通过 [6 + 4] 循环加法选择性产生 10 个环的基质的设计,这些发现提供了洞察力.
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