在水溶液中的糖的酸盐复合物
Joseph B Lambert1, Gang Lu, Stephanie R Singer
1Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA. jlambert@northwestern.edu
Journal of the American Chemical Society
|August 5, 2004
概括
某些糖类与酸形成可溶性酸复合物,但只有特定的花粉素形式反应. 这种选择性反应涉及无分子基组,对前生物化学有影响.
科学领域:
- 碳水化合物化学 碳水化合物化学
- 酸盐化学 酸盐化学
- 益生菌化学 益生菌化学
背景情况:
- 糖可以与酸反应,形成可溶性酸复合物.
- 糖的结构及其配置对于复杂的形成至关重要.
研究的目的:
- 调查糖-酸复合体形成的结构要求.
- 了解这种反应的选择性及其潜在影响.
主要方法:
- 核磁共振 (NMR) 谱学,特别是 (29) Si 和 (13) C NMR,用于分析产品.
- 研究了各种单糖和分糖与基本酸的反应.
主要成果:
- 只有糖的 furanose 形式与酸反应,形成 2/1 (糖/酸) 酸盐.
- 反应需要异构基组与相邻的基组相结合.
- 特定的糖类如核糖,糖和果糖形成复合物,而葡萄糖和银河糖则没有.
结论:
- 糖酸盐复合物的形成高度选择性,取决于糖的结构和基组的配置.
- 反应机制涉及通过五个成员的二氧化环进行化.
- 这种选择性可能在 prebiotic 化学过程中发挥作用.
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