化离子复合的阴离子依赖性 通过在甲溶液中的开链受体分子
Robert Pajewski1, Riccardo Ferdani, Jolanta Pajewska
1Department of Chemistry, Washington University, 1 Brookings Drive, St. Louis, Missouri 63130, USA.
Journal of the American Chemical Society
|December 22, 2005
概括
简单的序列通过胺NH接触有效地结合化物离子. 结构变化和溶剂相互作用影响结合,链条长度和proline位置显著影响复合强度.
科学领域:
- 超分子化学 超分子化学
- 类化学 类化学
- 分析化学 分析化学
背景情况:
- 类是多功能分子,在阳离子识别中具有潜在的应用.
- 了解宿主-客人相互作用对于设计选择性结合剂至关重要.
- 开放链提供了独特的结构灵活性来复杂化.
研究的目的:
- 为了研究短,开链的阴离子复合能力.
- 阐明和离子之间的结合机制.
- 确定影响 - 阴离子相互作用强度和选择性的因素.
主要方法:
- 合成和研究十七种基于GGGGGGGG的,具有多种不同的终结.
- 核磁共振 (NMR) 光谱检测分子相互作用.
- 循环二元化 (CD) 光谱法用于分析形状变化.
- 在不同的溶剂条件下进行约束常数测量.
主要成果:
- ,主要是GGGPGGG变体,表现出有效的离子复合.
- 核磁共振表明通过化物与胺NH接触的初级相互作用.
- CD光谱显示了离子结合时的构造变化.
- 结合常数对溶剂效应和链长度/proline位置敏感.
结论:
- 开链,特别是GGGPGGG衍生物,是有效的离子复合剂.
- 阳离子结合涉及特定的胺NH相互作用,并诱导构造变化.
- 溶剂相互作用在预先组织的结合中发挥作用.
- 序列的修改,包括长度和proline放置,显著调节复合效率.
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