グリコシドの反応性に対するコンフォーム効果:グルコースの高度に反応するコンフォーマーの研究
Ciaran McDonnell1, Oscar López, Paul Murphy
1Department of Chemistry, University College Dublin, Ireland.
Journal of the American Chemical Society
|September 30, 2004
まとめ
グルコースイドの形状は,その反応性に大きく影響する. 特に, (1) C (4) 形状は水解速度を劇的に増加させ,軸性ヒドロキシル群効果に関する理論を裏付けている.
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
- 生物物理化学 生物物理化学
背景:
- 炭水化物の反応性を理解するために,グリコシド構成は極めて重要です.
- (1) C (4) 形状は,反応性を高めるために提案されています.
- 以前の研究では,軸性ヒドロキシル群が電子の取り外しに影響することを示唆している.
研究 の 目的:
- グリコシドの反応性に対するコンフォーメーションの影響を調査する.
- 3,6-アンヒドログルコシドを,反応性 (1) C (((4) のグルコース構成のモデルとして使用する.
- 異なるアンヒドログルコシド誘導体の反応性を比較する.
主な方法:
- メチル3,6-アンヒドログルコシドおよび関連するオリゴサッカリドの合成.
- 制御された条件下での水解速度の研究.
- 研究されたグリコシドの構成分析.
主要な成果:
- メチル3,6-アンヒドロ-ベータ-D-グルコピラノシドは,4C(1) メチルグルコシドより200〜400倍速く水解されます.
- メチル3,6-アンヒドロベータ-D-ガラクトパイラノシドは,メチルベータ-D-ガラクトパイラノシドと比較して反応性が低下した.
- 合成されたオリゴサッカライドは,無水素残留物に対して選択的に反応した.
結論:
- グルコースイドの1C4形状は,それらを非常に反応性のある種にします.
- この反応性の向上は,軸性OH群が赤道性OH群よりも電子の引き出しが少ないという仮説を裏付けている.
- 適合効果は,グリコシド水解速度の重要な決定因子である.
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