Adenosine receptor inhibitor 2 (compound 14b) is a potent AR ( adenosine receptor ) inhibitor. Adenosine receptor inhibitor 2 shows dual affinity toward A 1 /A 2A ARs with higher affinity for the A 1 - than the A 2A AR. Adenosine receptor inhibitor 2 has K i values of 52.2 nM for the A 1 AR and 167 nM for the A 2A AR.