六基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基基
Veronica Iuliano1, Carmen Talotta1, Paolo Della Sala1
1Dipartimento di Chimica e Biologia "A. Zambelli", Università di Salerno, Via Giovanni Paolo II 132, I-84084 Salerno, Italy.
Molecules (Basel, Switzerland)
|June 28, 2023
概括
六基酸[6] (2b) 适应其形状,以结合线性或分支的基客. 结合和客人大小决定了复杂的稳定性,有分支的客人喜欢特定的形状.
科学领域:
- 超分子化学 超分子化学
- 主机和客人的化学反应
- 有机化学 有机化学
背景情况:
- 卡利沙伦是宏环化合物,以其形成宿主-客人复合物的能力而闻名.
- 素的形状灵活性使它们能够适应不同的客分子.
- 了解客体诱导的构造变化对于设计选择性分子识别系统至关重要.
研究的目的:
- 为了研究hexahexyloxycalix[6]arene (2b) 在与线性和分支的基客体复合时的构造性行为.
- 阐明结和硬质效应在确定结合亲和性和选择性的作用.
- 分析不同类型的基客体对2b的首选构造.
主要方法:
- 合成六基基[6] (2b) 和各种基客.
- 核磁共振 (NMR) 光谱学用于研究复杂的形成和确定结合常量.
- 非共价相互作用 (NCI) 和自然键轨道 (NBO) 计算来分析分子间相互作用.
主要成果:
- 赫萨赫西洛克西卡利克斯[6]arene (2b) 呈现适应性构造行为,根据客人采用形或1,2,3-替代构造.
- 线性n-pentylammonium诱导了圆形状,而分支的 tert-butylammonium 和 isopropylammonium 则有利于 1,2,3-替代形状.
- 结合 (N-H··O) 被认为是复杂稳定性的主要驱动力,因客体硬质量增加而减弱.
结论:
- 2b的构造选择是由结和与基客体的固体相互作用之间的平衡决定的.
- 1,2,3-替代和形形状提供最佳的结合机会,从而为分支客人带来更高的结合亲和力.
- 这项研究突出了基于卡利沙林的分子识别中形状适应性的重要性.
相关概念视频
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