2-Aryl-8-azaadenosines: structure-activity relationships in the binding with A1 and A2 receptors. A comparison with the corresponding 9-benzyl-8-azaadenines. III.

Several title compounds were assayed to determine their relative affinity towards the adenosine receptors. Selectivity ratios (SR) showed a prevalent A1 affinity. The comparison with the selectivity ratios of the corresponding 9-benzyl-8-azaadenines and the comparison between the affinity constant values (K1) for each receptor of the two series, were performed. The results led us to conclude that A1 receptors are characterized by more different arrangements which regard especially to 9-benzyl-8-azaadenines.