Structure–activity relationship studies of a new series of imidazo[2,1-f]purinones as potent and selective A3 adenosine receptor antagonists

We recently described the synthesis of 1-benzyl-3-propyl-1H,8H-imidazo[2,1-f]purine-2,4-diones, new potent and selective A3 adenosine receptor antagonists containing a xanthine core. The present work can be considered an extension of our SAR studies on related structures in which the effect of different kind of substitutions at the 1-, 3- and 8-positions has been evaluated in order to improve both the potency and the hydrophilicity of the originally synthesised molecules. The A3 binding disposition of these compounds was also investigated through docking and 3D-QSAR studies.