Novel 1,3-dipropyl-8-(1-heteroarylmethyl-1H-pyrazol-4-yl)-xanthine derivatives as high affinity and selective A2B adenosine receptor antagonists

A series of new 1,3-dipropyl-8-(1-heteroarylmethyl-1H-pyrazol-4-yl)-xanthine derivatives as A2B-AdoR antagonists have been synthesized and evaluated for their binding affinities for the A2B, A1, A2A, and A3-AdoRs. 8-(1-((3-phenyl-1,2,4-oxadiazol-5-yl)methyl)-1H-pyrazol-4-yl)-1,3-dipropyl-1H-purine-2,6(3H,7H)-dione (4) displayed high affinity (Ki = 1 nM) and selectivity for the A2B-AdoR versus A1, A2A, and A3-AdoRs (A1/A2B, A2A/A2B, and A3/A2B selectivity ratios of 370, 1100, and 480, respectively). The synthesis and SAR of this novel class of compounds are presented herein.

Graphical abstractWe describe the synthesis and biological activities of novel adenosine A2B receptor antagonists.Figure optionsDownload full-size imageDownload as PowerPoint slide