(8R)-8-ETHYL-1,4,7,8-TETRAHYDRO-4-5H-IMIDAZO[2,1-I]PURIN-5-ONE

PSB 11 Hydrochloride is a potent and selective antagonist of Adenosine receptor A3-R.

Potent and selective antagonist for the human adenosine A 3 receptor, with low affinity for the rat A 3 receptor (K i values are 2.3 and > 10000 nM respectively). Displays > 1000-fold selectivity over human A 1 and A 2A receptors (K i values are 4.1 and 3.3 μ M respectively) and > 180-fold selectivity over rat A 1 , rat A 2A and mouse A 2B receptors. Acts as an inverse agonist in the [ 35 S]GTP γ S binding assay in hA 3 -CHO cells (IC 50 = 36 nM).