High ligand efficiency quinazoline compounds as novel A_2A adenosine receptor antagonists

The past fifty years have been marked by the surge of neurodegenerative diseases. Unfortunately, current treatments are only symptomatic. Hence, the search for new and innovative therapeutic targets for curative treatments becomes a major challenge. Among these targets, the adenosine A_2A receptor (A_2AAR) has been the subject of much research in recent years. In this paper, we report the design, synthesis and pharmacological analysis of quinazoline derivatives as A_2AAR antagonists with high ligand efficiency. This class of molecules has been discovered by a virtual screening and bears no structural semblance with reference antagonist ZM-241385. More precisely, we identified a series of 2-aminoquinazoline as promising A_2AAR antagonists. Among them, one compound showed a high affinity towards A_2AAR (21a, K_i = 20 nM). We crystallized this ligand in complex with A_2AAR, confirming one of our predicted docking poses and opening up possibilities for further optimization to derive selective ligands for specific adenosine receptor subtypes.