原子のない保護基を用いた全D,全L,およびD-/L-オリゴサッカリドのDe novo非対称合成
Ravula Satheesh Babu1, Qian Chen, Sang-Woo Kang
1Department of Chemistry and Chemical Biology, Northeastern University, Boston, Massachusetts 02115, USA.
Journal of the American Chemical Society
|July 12, 2012
まとめ
この研究は,複雑なオリゴサッカライドを合成するための効率的な新しい方法を提示し,ステップを削減し,グループを保護します. このアプローチにより,生物学的および医学的研究のための多種多様なオリゴサッカライド構造が可能になります.
科学分野:
- 炭水化物化学 炭水化物の化学
- オーガニック・シンセシス オーガニック・シンセシス
- カタリシス カタリシス カタリシス
背景:
- オリゴサッカライドの合成は複雑で,複数のステップと選択的な保護/脱保護戦略が必要です.
- 既存の方法はしばしば非効率で,大量の廃棄物を生み出します.
- 多様なオリゴサッカライド構造への合理化され,原子経済的な経路が必要である.
研究 の 目的:
- 様々なオリゴサッカリドモチーフを合成するための非常に効率的な新しい経路を開発する.
- 生物学的および医薬品の構造-活性研究のためのオリゴサッカリドの生産を可能にします.
- オリゴサッカリド合成における非対称な触媒と緑化学の原理の応用を紹介する.
主な方法:
- 非対称な触媒を用いて,特にPd(0) 触媒によるグリコシライゼーションとグリコシライゼーション後の反応.
- 化学選択的なC-CとC-Oのπ結合機能を原子のない保護グループとして採用しています.
- ステレオ制御のために,Pd-π-アルリル中間体を通したアノメリック・ディレクティング・グループを活用する.
主要な成果:
- 自然と非自然な形態を含む多様なオリゴサッカライドの非常に効率的で原子経済的な合成を達成しました.
- d-/l-ダイアステロエーマーとデオキシ糖の合成を実証した.
- アキラルの前体からわずか12のステップで35のステレオセンターを持つ高度に枝分かれしたヘプタサッカリドを成功裏に構築しました.
結論:
- 開発された経路は,オリゴサッカリド合成の効率を大幅に高めます.
- この方法は,従来のアプローチよりも,よりグリーンで,より原子経済的な代替案を提供します.
- この戦略は,さらなる研究のために,幅広いオリゴサッカリド構造へのアクセスを提供します.
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