Studies on the interaction of phosphate anions with N-functionalised polyaza[n]paracyclophanes: the role of N-methylation

Abstract

The synthesis and interaction of N,N′,N″,N‴-tetramethyl-2,6,9,13-tetraaza[14]paracyclophanes (B323Me₄) with nucleotides and inorganic phosphates is described. An easy methodology is used to define thermodynamic selectivity. The interaction of B323Me4 and ATP has been monitored by ¹H, ³¹P NMR and by molecular mechanics, ruling out the possibility of the participation of π-stacking interactions. Results show that N-methylation is accompanied by a strong increase in the interaction of the resulting macrocycle with ATP.