分子間激素結合とPd触媒サイクリングによって可能になったタクソルの総合成
Takahiro Watanabe1, Kyohei Oga1, Hiroaki Matoba1
1Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo113-0033, Japan.
Journal of the American Chemical Society
|November 16, 2023
まとめ
研究者らは,複合的な抗腫瘍性ディテルペノイドであるTaxol (1) の完全な合成を達成した. この28段階の合成は,複雑な四環構造の効率的な構築のために,新しい断片設計とラジカルカップリングを使用しました.
科学分野:
- 有機化学
- 自然製品合成
- 薬剤化学
背景:
- タクソール (1) は,複雑な四環構造を持つ重要な抗腫瘍性ディテルペノイドである.
- 濃厚な酸素濃度と 独特の環系は 重要な合成課題を 提示しています
研究 の 目的:
- 複合天然産物Taxol (1) の収束した全合成を報告する.
- 複雑なテルペノイド合成のための新しい断片設計とラジカルカップリング戦略を実証する.
主な方法:
- コンバージェント・シンセシスアプローチ
- ブロモサイクロヘクセノンとテトラヒドロフランのリングを組み込んだ断片ベースの設計.
- 分子間連結用ラジカル前駆体 (α-アルコキシアシルテルリド)
- パラジウム触媒によるB環形成
- ステレオセレクティブ・コンストラクションのC8四角性ステレオセンター
主要な成果:
- タクソルの28段階の全合成が成功しました (1).
- 主要ステレオセンター (C2,C3,C8) の効率的な設置は,ラジカルカップリングとステレオ選択反応を用いて行われます.
- Pd(0) -触媒化されたサイクリングによる中央の8つ構成のBリングの形成.
- テトラサイクルコアとオクセタンDリングの完成
結論:
- 開発された合成戦略は,濃度の高い酸素を持つテルペノイドを製造するための貴重な青写真を提供します.
- 断片設計とラジカルカップリングの方法論は 複雑な天然製品への効率的な経路を提供します
- この合成は,天然製品の総合合成と医薬品化学の分野を進めている.
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