N(6) or N(9) substituted 2-phenyl-8-azaadenines: affinity for A1 adenosine receptors. VII

The A1 activities shown respectively by N(6) or N(9) substituted 8-azaadenines were compared. At least in some cases, the biological results indicated the ability of the receptor to accept the exogenous molecule in various arrangements, and an attempt to rationalizing these arrangements was made by means of a model with two different molecular orientations.