Ye Yanan, Ma Peihua, Ma Yue, Yang Naqin, Chen Xiaoqian, Yang Xinan, Shen Lingyi, Xiao Xin
Key Laboratory of Macrocyclic and Supramolecular Chemistry of Guizhou Province, Institute of Applied Chemistry, Guizhou University Guiyang 550025 China
Guiyang College of Humanities and Science Guiyang 550025 China.
RSC Adv. 2024 Jan 16;14(4):2652-2658. doi: 10.1039/d3ra07810h. eCollection 2024 Jan 10.
Cucurbit[]urils (Q[]s) are a class of supramolecular host compounds with hydrophilic carbonyl ports and hydrophobic cavities, which can selectively form host-guest inclusion complexes with guest molecules to change the properties of guest molecules. In this paper, tetramethyl cucurbit[6]uril (TMeQ[6]) was used as the host and three 2-heterocyclic substituted benzimidazole derivatives as the guests, and their modes of interaction were investigated using X-ray crystallography, H NMR spectrometry, and other analytical techniques. The results showed that TMeQ[6] formed a 1 : 1 host-guest inclusion complex with three guest molecules, and the binding process between them was mainly enthalpy-driven. The X-ray diffraction analysis indicated that the main driving forces for the formation of these three inclusion complexes included hydrogen bonding interactions and ion dipole interactions. There are two modes of interaction between G3 and TMeQ[6] in the liquid phase, indicating that the benzimidazole ring and heterocyclic substituents on the guest molecule compete with the cavity of TMeQ[6]. Besides, the addition of TMeQ[6] significantly enhanced the fluorescence of these guests and slightly improved their solubility.
葫芦脲（Q[n]s）是一类具有亲水性羰基端口和疏水性空腔的超分子主体化合物，其能够与客体分子选择性地形成主客体包合物，从而改变客体分子的性质。本文以四甲基葫芦[6]脲（TMeQ[6]）作为主体，三种2-杂环取代苯并咪唑衍生物作为客体，采用X射线晶体学、核磁共振氢谱等分析技术研究了它们的相互作用模式。结果表明，TMeQ[6]与三种客体分子形成了1:1的主客体包合物，且它们之间的结合过程主要由焓驱动。X射线衍射分析表明，这三种包合物形成的主要驱动力包括氢键相互作用和离子偶极相互作用。在液相中，G3与TMeQ[6]之间存在两种相互作用模式，这表明客体分子上的苯并咪唑环和杂环取代基与TMeQ[6]的空腔存在竞争。此外，加入TMeQ[6]显著增强了这些客体的荧光，并略微提高了它们的溶解度。
