替代剂对水中的芳香相互作用的影响
Gloria Tobajas-Curiel1, Qingqing Sun2,3, Jeremy K M Sanders1
1Yusuf Hamied Department of Chemistry, University of Cambridge Cambridge CB2 1EW UK herchelsmith.orgchem@ch.cam.ac.uk.
Chemical science
|June 16, 2023
概括
在水中的分子识别是复杂的,但明确的超分子复合体揭示了关键因素. 客分子上的替代物通过溶解的热贡献显著增强结合亲和力.
科学领域:
- 超分子化学 超分子化学
- 物理有机化学 有机化学
- 分子识别分子识别
背景情况:
- 由于复杂的相互作用,如溶解和形状变化,在水中的分子识别具有挑战性.
- 在不同的溶剂中研究明确的超分子复合物有助于剖析这些贡献.
- 卡利克斯[4]醇受体和胺N-氧化物客体形成适合此类研究的稳定综合体.
研究的目的:
- 用[4]pyrrole-pyridine N-oxide复合物剖析控制水中芳香相互作用的替代效应的因素.
- 量化芳香相互作用和替代剂对复合物稳定性的热力学贡献.
- 为了比较水中的替代效应与非极性溶剂 (如) 中的替代效应.
主要方法:
- 在四个calix[4]pyrrole受体和十三个pyridine N-oxide客体之间形成1:1复合体.
- 使用化学双突变周期量化热力学贡献.
- 实验技术包括异热定位热量计和1H NMR竞争实验.
主要成果:
- 受体和客体基之间的芳香相互作用使复合体稳定1000倍.
- 客体基上的替代剂进一步提高了稳定性,高达1000倍,基替代剂产生了370 fM解离常数.
- 在水中增强的替代效应归因于来自疏水表面溶解的有利热贡献.
结论:
- 灵活的受体结构有助于极性替代物的解溶,最大限度地提高与受体的非极性相互作用和与溶剂的极性相互作用.
- 这些优化的相互作用导致在水性介质中具有非常高的结合亲和度.
- 静电相互作用起着重要的作用,特别是在非极性溶剂中,而在水中则占主导地位.
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