ヘロナミドAのバイオシンセシスのトランスアヌーラ [6 + 4] とアンビモダルサイクロアディション
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
まとめ
密度関数理論モデリングは,ヘロナミドA生物合成における提案された環横 [6 + 4] サイクル添加を支持する. この反応はステレオセレクティブであり,安定した [6 + 4] アドクトを [4 + 2] アドクトに与えます.
科学分野:
- 有機化学
- コンピュータ化学
- 生物化学
背景:
- ヘロナミドAのバイオシンセシスは,提案された環状 [6 + 4] サイクル添加を含みます.
- この重要なステップを理解することは,天然の産物形成の解明に不可欠です.
研究 の 目的:
- ヘロナミドA生物合成における提案された環横 [6 + 4] サイクロアディションをモデル化し,検証する.
- 反応経路のステレオ選択性と熱力学的安定性を調査する.
主な方法:
- 密度関数理論 (DFT) の計算を用いた.
- 反応機構,移行状態,アダクトの安定性の分析が行われました.
主要な成果:
- 提案された [6 + 4] サイクル添加は高度にステレオセレクティブで,単一の主要な製品を生成します.
- 双方向の移行状態は [6 + 4] と [4 + 2] の両方を誘導する.
- [6 + 4] 誘導体は,熱力学的に [4 + 2] 誘導体に 5.2 kcal mol ((-1) で優れている.
- コップの再編成は [6 + 4] と [4 + 2] のアドクトの相互変換を可能にします.
結論:
- 計算結果は,ヘロナミドA生物生成における環状 [6 + 4] サイクル添加の妥当性を強く支持する.
- 発見は, [6 + 4] サイクロアディションで選択的に10個環を生成する基板の設計のための洞察を提供します.
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