Synthesis of hypermodified adenosine derivatives as selective adenosine A3 receptor ligands (original) (raw)

We investigated the A 3 AR affinity and selectivity of a series of 2-substituted 3 0 -azido and 3 0 -amino adenosine derivatives as well as some 5 0 -uronamide derivatives thereof. All compounds showed high A 3 AR selectivity. While the 3 0 -azides appeared to be A 3 AR antagonists with moderate A 3 AR affinity, their 3 0 -amino congeners exhibit significantly improved A 3 AR affinity and behave as partial agonists. For both the 3 0 -azides and the 3 0 -amines, the 5 0 -methylcarbamoyl modification improved the overall affinity. Introduction of a 2-phenylethynyl substituent provided high affinity for the A 3 AR.