4,6-アセタル基が,グリコシド反応性 (トルション性または電子性) に与える抑制効果は,
Henrik Helligsø Jensen1, Lars Ulrik Nordstrøm, Mikael Bols
1Department of Chemistry, University of Aarhus, 8000 Aarhus C, Denmark.
Journal of the American Chemical Society
|July 30, 2004
まとめ
4,6-アセタル保護群である.
科学分野:
- 炭水化物化学 炭水化物の化学
- 有機化学 オーガニック・ケミストリー
- グライコシレーション反応 グライコシレーション反応
背景:
- 4,6-アセタル保護群は,グリコシル移転を無効化することが知られている.
- この無効化の正確なメカニズム (トルション対電子) は議論されている.
- このメカニズムを理解することは,グリコシル化反応の制御に極めて重要です.
研究 の 目的:
- 4,6-アセタル保護群の無効作用がトルション的か電子的かを判断する.
- tg適合性における6-OH固定の役割を調査する.
- 形状的にロックされたおよび柔軟なグリコシドの水解速度を比較する.
主な方法:
- 形状的にロックされたプローブ分子 (18Rと18S) と柔軟なアナログ (21と26) の合成.
- 探査機分子および同類のpH6.5での水解速度の測定.
- 同様のメチルアルファグリコシド (17S,17R,19) の酸性水解速度の比較
主要な成果:
- pH 6.5の水解速度は,次の順番に従った: 21 > 18R > 18S > 26.
- 4,6-メチレングループの無効作用は,トルションおよび電子的要因の組み合わせです.
- (4) C (((1) 形状のロックされたサッカリドは,水解が著しく遅いことを示した.
- ハイドロキシメチルロタマーは,g >> gt > ggの順にグリコシド水解を無効化する.
結論:
- 4,6-アセタル保護グループによる無効化は,トルションと電子の両方である.
- tg形状に6-OHを固定すると,無活性化に寄与する.
- 形状的にロックされたグリコシドは,グリコシル伝達率に影響を与える要因の洞察を提供します.
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