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

The synthesis and interaction of N, N', N", N'''-tetramethyl- 2,6,9,13-tetraaza[14] paracyclophanes (B323Me(4)) with nucleotides and inorganic phosphates is described. An easy methodology is used to de. ne thermodynamic selectivity. The interaction of B323Me4 and ATP has been monitored by H-1, P-31 NMR and by molecular mechanics, ruling out the possibility of the participation of pi-stacking interactions. Results show that N-methylation is accompanied by a strong increase in the interaction of the resulting macrocycle with ATP.