DESIGN AND SYNTHESIS OF IONOPHORES WITH MULTIPLE RECEPTOR-SITES - SOLUTION NUCLEAR-MAGNETIC-RESONANCE STUDIES OF THEIR INTERACTION WITH CHLORIDE, SODIUM AND POTASSIUM-IONS

Ionophores of the bis(crown ether) type, with polyamine linkers, examples of which are known to bind Simultaneously to a cation and its counter anion, have been prepared. One-pot reductive amination, used to couple a benzo-crown aldehyde with aliphatic (both linear and cyclic) and aromatic polyamines. proved to be the most efficient route. A strong inhibition of one synthetic route (amine benzylation) was observed. The competitive interaction between chloride and other anions for binding with the protonated ionophores was examined using Cl-35 NMR spectroscopy. Sandwich complexing of potassium contrasting with single-face complexation of sodium was demonstrated by C-13 NMR Spectroscopy