ティオニウムイオンの誘発による中型環形成:アステリスクノリドDの全合成
Barry M Trost1, Aaron C Burns, Mark J Bartlett
1Department of Chemistry, Stanford University, Stanford, California 94305-5080, USA. bmtrost@stanford.edu
Journal of the American Chemical Society
|January 13, 2012
まとめ
研究者らは,自然産物であるアステリスクノリドDを初めて合成した. この9段階のプロセスは,ストレングマクロサイクルを効率的に作り,最も生物学的に活性な形態を生成しました.
科学分野:
- 有機化学 オーガニック・ケミストリー
- 自然製品合成 自然製品合成
- 薬用化学 薬用化学について
背景:
- ヒュミュレンの天然製品は,重要な生物学的活性を示しています.
- アステリスクノリドDは,11個の環状構造を持つ複雑な分子です.
- 以前の合成経路では,アステリスクノリドDの最も生物学的活性な形態にアクセスできませんでした.
研究 の 目的:
- アステリスクノリドDの最初の完全合成を達成するために.
- 保護グループのない合成戦略を開発する.
- アステリスクノリドDの最も生物学的に活性な同位体にアクセスするために.
主な方法:
- ダイアステレオセレクティブのチオニウムイオンがサイクリングを開始して11個の環を形成した.
- 選択的なE-オレフィン形成のためのステレオ固有のチオエーテル活性化-除去.
- Zn-ProPhenolで触媒化されたエナチオセレクティブ添加とRu-触媒化されたアルケン-アルキン結合により,立体化学的制御とブテノリド形成が行われます.
主要な成果:
- 保護基なしでアステリスクノリドDの9段階合成に成功.
- 新しいサイクライゼーション戦略を用いて,ストレインされた11基のマクロサイクルの形成.
- ステレオセレクティブ合成により,最も生物学的活性のあるアステリスクノリドD同位体へのアクセスを提供します.
結論:
- 開発された合成経路は効率的で,集団の保護を回避します.
- この合成は,生物学的に活性なアステリスクノリドD.へのアクセスに信頼できる方法を提供します.
- この研究は,複雑な天然製品の合成を進めて,さらなる生物学的研究を促進します.
関連する概念動画
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Halogenation is another class of electrophilic addition reactions where a halogen molecule gets added across a π bond. In alkynes, the presence of two π bonds allows for the addition of two equivalents of halogens (bromine or chlorine). The addition of the first halogen molecule forms a trans-dihaloalkene as the major product and the cis isomer as the minor product. Subsequent addition of the second equivalent yields the tetrahalide.
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