Anion complexation and sensing using modified urea and thiourea-based receptors

This critical review highlights recent advances in the structurally modified (thio) urea-based receptors for anion complexation and sensing. Modifications of the (thio) urea structure are aimed at a better anion binding in terms of higher binding constant, anion selectivity and feasibility. Major (thio) urea receptors are reviewed as N-alkyl, N-aryl and N-amido/N-amino (thio) ureas. Hints for designing (thio) urea-based receptors for anions are discussed (102 references).