Native Quercetin as a Chloride Receptor in an Organic Solvent

The binding properties of quercetin toward chloride anions were investigated by means of 1H-NMR, 13C-NMR, and electrospray ionization mass spectrometry (ESI-MS) measurements, as well as computational calculations. The results indicate that quercetin behaves primarily as a ditopic receptor with the binding site of the B ring that exhibits stronger chloride affinity compared to the A ring. However, these sites are stronger receptors than those of catechol and resorcinol because of their conjugation with the carbonyl group located on the C ring. The 1:1 and 1:2 complexation of this flavonoid with Cl− was also supported by ESI mass spectrometry.

Cooperative binding and extraction of sodium nitrite by a ditopic receptor incorporated into a polymeric resin

The modular design of ion pair receptors facilitated the preparation of a functionally analogous polymeric material able to extract sodium nitrite from acetonitrile solution.

Ion pair complexes and anion binding in the solution of a ditopic receptor

A comprehensive solid-state and solution study of a ditopic benzo-15-crown-5 bis-urea receptor L toward alkali halides has been presented.

An unprecedented porphyrin-pillar[5]arene hybrid ditopic receptor

A porphyrin-pillar[5]arene hybrid host compound with a ditopic receptor nature was synthesized for the first time, which combines a neutral 1,4-bis(imidazol-1-yl)butane guest by means of its two active centers to form a stable supramolecular complex.

Phosphate binding by a novel Zn(ii) complex featuring a trans-1,2-diaminocyclohexane ligand. Effective anion recognition in water

Excellent affinities and selectivities toward triphosphates are achieved through an adaptive ditopic receptor featuring a metal ion and a macrocyclic polyammonium cation binding sites, concertedly bridging phosphate anions.