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Updated: Jun 24, 2026

Collecting Variable-concentration Isothermal Titration Calorimetry Datasets in Order to Determine Binding Mechanisms
Published on: April 7, 2011
Tunability of anion binding strength based on acyl-thiourea receptors containing isatin group
Shuzhen Hu1, Yong Guo, Jian Xu
1Key Laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, PR China.
Abstract:
Some acyl-thiourea derivatives containing isatin group were synthesized and their interactions with anions were investigated using UV-vis spectroscopy and (1)H NMR titrations in DMSO and DMSO-d(6), respectively. These compounds have a same molecular framework, functionalising with different groups lead to different anion binding strength of these receptors. Receptor 1 showed a higher binding affinity for AcO(-) than for F(-), due to the cooperative multiple hydrogen bond interactions of AcO(-) with the acyl-thiourea group and N-H group in the indole unit of receptor 1. Displacing the N-H proton in the indole unit with -CH(3) group, receptor 2 showed no obviously discriminative responses for F(-), AcO(-) and H(2)PO(4)(-) due to lack of such additional binding. In the case of receptor 3, which was functionalised with strong electron-withdrawing group, it showed selectively chromogenic response for F(-) based on double deprotonation of the receptor in DMSO, whereas AcO(-) and H(2)PO(4)(-) induced single deprotonation only.
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