(-) -キノカルシンの非対称的全合成

Yan-Chao Wu¹, Mélanie Liron, Jieping Zhu

¹Institut de Chimie des Substances Naturelles, CNRS, 91198 Gif-sur-Yvette Cedex, France.

Journal of the American Chemical Society

|May 6, 2008

まとめ

(-) - キノカルシンの全合成は22段階で行われました. 重要なステップには,ピクテ・スペングラー反応と,銀を触媒とするマニッヒ反応が含まれ,複雑なペンタサイクルの構造を構成した.

科学分野:

有機化学オーガニック・ケミストリー
合成化学合成化学について

背景:

(-) -キノカルシンは複雑なペンタサイクルの天然産物です.
以前の合成経路は限られたか不完全であった.

研究の目的:

(-) -キノカルシンの全合成を達成するために.
複雑な分子構造のための新しい合成方法論を開発する.

主な方法:

3ヒドロキシベンザルデヒドから始まる22段階の線形合成.
テトラヒドロアイソキノリンの形成にピクテ・スペングラー反応を用いた.
ダイアザビサイクロ[3,2,1]-オクタン核を構成するために,銀で触媒化された分子内マニッヒ反応を使用した.

主要な成果:

(-) -キノカルシン.の総収率は16%を達成しました.
ピクテ・スペングラー反応は,望ましい1,3-シス立体同位体のみ (91%) を生み出した.
アミナルからアミノチオエーテルへの新しいHf(OTf) 4-触媒変換を開発しました.

結論:

(-) -キノカルシンの全合成が成功裏に完了しました.
開発された合成戦略は,他の複雑な天然製品にも適用できます.
この研究は,挑戦的なサイクライゼーションのための特定の反応条件の重要性を強調しています.

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