Allosteric binding properties of a 1, 3-alternate thiacalix[4]arene-based receptor having phenylthiourea and 2-pyridylmethyl moieties on opposite faces. (31st August 2021)

• Record Type: Journal Article
• Authors: Rahman, Shofiur; Tomiyasu, Hirotsugu; Wang, Chuan-Zeng; Georghiou, Paris E.; Alodhayb, Abdullah; Carpenter-Warren, Cameron L.; Elsegood, Mark R. J.; Teat, Simon J.; Redshaw, Carl; Yamato, Takehiko
• Is Part Of: New journal of chemistry. Volume 45:Number 41(2021)
• Page Start: 19235
• Page End: 19243
• Publication Date: 2021-08-31
• Subjects: Chemistry -- Periodicals; Chimie -- Périodiques; 540
• DOI: 10.1039/d1nj02991f
• Languages: English
• ISSNs: 1144-0546

Abstract

Abstract : Thiacalix[4]arene receptors with two thiourea moieties and two 2-pyridyl moieties exhibited a heteroditopic dinuclear receptor with F − and Ag + ions by a positive allosteric effect. Abstract : The synthesis of three new heteroditopic receptors (5a–c ) which are based on thiacalix[4]arenes in the 1, 3-alternate conformation is reported herein. These new receptors each have two thiourea moieties linking phenyl groups, two of which are substituted with electron-withdrawing groups at their para -positions, and at the opposite side of the thiacalix[4]arene cavity, with two 2-pyridylmethyl groups. One example (5a ) was also characterized by X-ray crystallography. A limited 1 H-NMR and UV-vis anion complexation study was conducted. DFT computational determinations indicated that 5c, which has strongly electron-withdrawing NO2 groups, had the most effective recognition ability towards the selected anions. The binding of Ag + at the 2-pyridyl moieties, and the binding of the anions at the two thiourea NH groups of the p -substituted phenylthioureido moieties, respectively, was also investigated. The appearance of a positive allosteric effect with receptor 5b was also found using 1 H-NMR titration experiments.