The synthesis of different diazonium salts derived from homo-and heterocyclic aromatic amines bearing anionic residues is described. The chemical stabilities of these compounds were established at different pH's, and the compounds were tested accordingly in binding experiments for the rat brain y-aminobutyric acid (GABA) receptor, for which they could ultimately be used as irreversible affinity or photoaffinity probes. The aromatic heterocyclic ...