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解开石 (n = 7,8) 和阴离子钻石之间的结构亲和关系
David Sigwalt1, Marina Šekutor2, Liping Cao1
1Department of Chemistry and Biochemistry, University of Maryland , College Park, Maryland 20742, United States.
Journal of the American Chemical Society
|February 10, 2017
概括
黄瓜 (CB[7]和CB[8]) 与阿达曼坦和钻石客体具有强烈的结合. CB[8]表现出女性结亲和力,表明它有可能成为CB[n]家族中最紧密的结合宿主.
科学领域:
- 超分子化学
- 主机与客户之间的化学反应
- 核磁共振光谱学
背景情况:
- 黄瓜 (CB[n]) 是具有独特腔结构的宏循环宿主.
- 对于设计新型的超分子系统来说, 了解客体结合关系至关重要.
研究的目的:
- 用于测量各种阿达曼坦和钻石衍生物的甲[7]uril (CB[7]) 和甲[8]uril (CB[8]) 的结合常量 (Ka).
- 调查影响结合亲和力的因素,包括客体结构,离子双极相互作用和门户几何.
- 探索增强CB[n]主机-客户复合体稳定的策略.
主要方法:
- 直接和竞争性的1H核磁共振光谱测定结合常数.
- 用X射线结晶学分析客体结合的结构基础.
- 非实证的量子力学计算来估计吉布斯结合的自由能量.
主要成果:
- CB[7]和CB[8]对阿达曼坦和钻石客体具有显著的结合亲和力.
- CB[8]·IsoDiam(NHMe2)2复合体表现出与CB[7]·Diam(NMe3)2相似的女性分子结合亲和力.
- 客体几何和门户互动显著影响结合,CB[8]显示了特定循环策略的更大的亲和力增强.
- 基化没有像预期的那样增加结合亲和力.
- 结构分析显示了特定的几何约束和影响结合模式的密切接触.
结论:
- CB[8]表现出特殊的结合能力,将其定位为CB[n]家族中最紧密的结合主体的有希望的候选者.
- 这项研究通过了解结构和电子因素,为优化主机-客户互动提供了洞察力.
- 基于CB的系统的进一步开发可能会导致分子识别和封装的先进应用.
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