| Summary: | A new simple urea-based dipodal molecular cleft (<b>L</b>) has been synthesized and studied for its binding affinity for a variety of anions by <sup>1</sup>H-NMR, UV-Vis and colorimetric techniques in DMSO-<i>d<sub>6</sub></i> and DMSO, respectively. The results from titration studies suggest that the receptor forms a 1:2 complex with each of the anions used via hydrogen bonding interactions and exhibits strong selectivity for fluoride among halides, showing the binding affinity in the order of fluoride > chloride > bromide > iodide; meanwhile, it displays moderate selectivity for acetate among oxoanions, showing the binding affinity in the order of acetate > dihydrogen phosphate > bicarbonate > hydrogen sulfate > nitrate. Colorimetric studies of <b>L</b> for anions in DMSO reveal that the receptor is capable of detecting fluoride, acetate, bicarbonate and dihydrogen phosphate, displaying a visible color change in the presence of the respective anions.
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