反応剤制御型ステレオセレクティブ合成α-グルカン
Liming Wang1, Herman S Overkleeft1, Gijsbert A van der Marel1
1Leiden Institute of Chemistry , Leiden University , Einsteinweg 55 , 2333 CC Leiden , The Netherlands.
Journal of the American Chemical Society
|March 20, 2018
まとめ
研究者はシス-グルコシド結合の構築のためのステレオ選択的グリコシレーション方法を開発した. この戦略は,特定のドナー-受容体の反応剤の活性化を制御し, Mycobacterium tuberculosis のノンサッカリドのような複雑な炭水化物の効率的な合成を可能にします.
科学分野:
- 炭水化物の化学
- 有機合成
- グライコバイオロジー
背景:
- ドナー-受容体の性質の変動により,グリコシド結合のステレオ選択的合成は困難である.
- グライコシレーションの結果を制御するには,反応剤と保護基の正確な調整が必要です.
研究 の 目的:
- シス-グルコシド結合のステレオ選択的合成のための一般的な方法を開発する.
- 異なるアルコールの核愛性 (プライマリーとセカンダリー) に適応可能な戦略を実証する.
主な方法:
- 単一のタイプのグリコシルドナー (per-benzylated glucosyl imidate) を使用した.
- ベンジルエーテルのみを使用する保護グループ戦略を採用しました.
- 特定の反応剤の組み合わせでドナーを活性化した (二次アルコールのTMSOTf/DMF,一次アルコールのTMSI/Ph3PO).
主要な成果:
- シス-グルコシド結合の完全ステレオ選択的設置を達成した.
- 受容器の反応性と反応剤の選択に基づいて,差異的な活性化が実証されている.
- Mycobacterium tuberculosisのノンサッカリドのモジュール合成に成功しました.
結論:
- 開発された戦略は,グリコシレーションにおけるステレオ選択性に対する正確な制御を提供します.
- この方法は,複雑なオリゴサッカライドを合成するための多用途なアプローチを提供します.
- この発見は,炭水化物の合成と糖生物学の研究を進める上で重要なものです.
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