二重C ((sp3) -H活性化により有効な (-) エピコシンGと (-) ロストラチンAの効率的かつ異なる全合成
Pierre Thesmar1, Olivier Baudoin1
1Department of Chemistry , University of Basel , St. Johanns-Ring 19 , CH-4056 Basel , Switzerland.
Journal of the American Chemical Society
|September 27, 2019
まとめ
研究者は, (-) - エピコシンGと (-) - ロストラチンAを含む複雑なディチオジケトピペラジンのためのスケーラブルな合成を開発した. この突破は 生物学的活性のある天然製品への 重要なアクセスを提供し 更に研究を進めています
科学分野:
- 有機化学
- 自然製品合成
- 薬剤化学
背景:
- ディチオジケトピペラジンは,重要な生物学的活動を持つ複合的多循環性天然産物です.
- これらの化合物の総合成は困難で,報告された例は限られている.
- この重要な分子に アクセスできる合成経路は ほとんどありません
研究 の 目的:
- 2つの対称的なペンタサイクルのディチオジケトピペラジン: (-) - エピコシンGと (-) - ロストラチンAのエナンチオセレクティブ,スケーラブル,そして分散した総合成を達成するために.
- 複雑なポリサイクルコアの構築のための効率的なキーステップを開発する.
- 研究不足の天然製品にアクセスするための信頼できる方法を提供すること.
主な方法:
- ステレオ制御のためのエナンチオセレクティブ有機触媒エポキシデーション.
- 二重のC ((sp3) -H活性化で同時にリングを構成する.
- 商業的に利用可能な材料からマルチグラムスケール合成.
- トランスフューズリングシステムに挑戦する反応条件の最適化.
主要な成果:
- マルチグラムスケールで共通の中間物質の合成を成功させた.
- 500 mgのスケールで (-) - ロストラチンAの初合成.
- 目標の天然産物の両方に対して,高い総収穫量 (13~20%) を達成した.
- 合成戦略のスケーラビリティとディバージェンスを示した.
結論:
- 開発された合成経路は, (-) - エピコシンGと (-) - ロストラチンAへの効率的なアクセスを可能にします.
- この研究は,ディチオディケトピペラジンの生物学的活動に関するさらなる調査を容易にする.
- この方法論は,他の関連する天然製品の合成にも適用できます.
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