TaBOX: A water-soluble tetraanionic rectangular molecular container for conjugated molecules and taste masking for berberine and palmatine

A water-soluble macrocycle that bears four carboxylate anions has been designed and prepared, which forms a rectangular cavity that can efficiently encapsulate discrete electron-deficient aromatic compounds, including berberine and palmatine. This macrocycle is revealed to be highly biocompatible and able to inhibit the bitter taste of the two drugs.