Selective Recognition and Sensing of Biologically Important Phosphates Using Triptycene-Based Anion Receptors

The principal aim of supramolecular chemistry is to design receptors that exhibit a level of selectivity and efficiency comparable to biological receptors and enzymes. Despite recent advances in the field, achieving high selectivity for a specific molecular guest remains a major challenge. Here, we present a systematic study of the anion-binding properties of triptycene-based receptors. Fluorescence titration experiments reveal that receptor 1 exhibits strong selectivity for monophosphate anions derived from nucleotides such as AMP, deoxy-AMP, CMP and UMP with binding constants ranging from 6637 to over 100000 M-1. In contrast, receptor 1 does not bind phosphate anions derived from cyclic AMP or ADP, as evidenced by the absence of any measurable changes in fluorescence spectra.