离子-碳化合物和/或离子-离子相互作用:合成宿主中的直接和反向霍夫迈斯特效应
Jacobs H Jordan1, Corinne L D Gibb1, Anthony Wishard1
1Department of Chemistry , Tulane University , New Orleans , Louisiana 70118 , United States.
Journal of the American Chemical Society
|March 14, 2018
概括
在具有明显结合点的宿主分子中,可极化离子触发霍夫迈斯特效应并逆转霍夫迈斯特效应. 离子结合导致电荷减弱,聚合和沉,显示出复杂的溶液行为.
科学领域:
- 超分子化学
- 物理化学
- 解决方案化学
背景情况:
- 霍夫迈斯特效应描述了蛋白质溶解性和行为的离子特异性扰动.
- 了解宿主与客人的相互作用对于设计功能分子系统至关重要.
- 合成受体中的离子结合可以调节溶液特性.
研究的目的:
- 研究极化离子对宿主-客体复合的影响.
- 在合成宿主中阐明霍夫梅斯特背后的机制和逆转霍夫梅斯特效应.
- 描述阴离子与宿主不同部位的结合亲和性和选择性.
主要方法:
- 质子核磁共振 (H NMR) 光谱检测结合相互作用.
- 动态光散射 (DLS) 来评估粒子大小和聚合.
- 测量度以监测降水情况.
主要成果:
- 阳离子对"软"非极性口袋和"硬"阳离子位表现出相似的亲和力.
- 在低度 (∼2 mM) 的离子结合会诱导宿主-客结合的霍夫迈斯特效应.
- 阳离子结合导致电荷减弱,聚合和沉 (反向霍夫迈斯特效应).
- 阻断非极端口袋减弱了反面的霍夫迈斯特效应.
结论:
- 在研究的主体中,可极化离子会诱导和逆转霍夫迈斯特效应.
- 主体的独特结合点在调解这些效应方面发挥着关键作用.
- 阴离子诱导的沉与电荷减弱和聚合有关,由特定的结合点相互作用调节.
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