Anion binding and transport properties of cyclic 2,6-bis(1,2,3-triazol-1-yl)pyridines

A series of cyclic 2,6-bis-(1,2,3-triazolyl)-pyridine anion receptors with thiourea functionalities were synthesized by click reaction of 2,6-diazidopyridine with protected propargylamine followed by condensation of a bisthiocyanate derivative with a series of diamines. Their chloride binding affinities as well as their transport properties in POPC bilayers were examined. These receptors were found to function as anion carriers, which can mediate both Cl⁻/NO₃⁻ antiport and H⁺/Cl⁻ symport, and the transport activity of these hosts were dominated by their lipophilicity.