936252-88-9Relevant articles and documents
Structure-activity relationships of 2,N6,5′-substituted adenosine derivatives with potent activity at the A2B adenosine receptor
Adachi, Hayamitsu,Palaniappan, Krishnan K.,Ivanov, Andrei A.,Bergman, Nathaniel,Gao, Zhan-Guo,Jacobson, Kenneth A.
, p. 1810 - 1827 (2007)
2, N6, and 5′-substituted adenosine derivatives were synthesized via alkylation of 2-oxypurine nucleosides leading to 2-arylalkylether derivatives. 2-(3-(Indolyl)ethyloxy)adenosine 17 was examined in both binding and cAMP assays and found to be a potent agonist of the human A2BAR. Simplification, altered connectivity, and mimicking of the indole ring of 17 failed to maintain A2BAR potency. Introduction of N6-ethyl or N6-guanidino substitution, shown to favor A2BAR potency, failed to enhance potency in the 2-(3-(indolyl)- ethyloxy)adenosine series. Indole 5″- or 6″-halo substitution was favored at the A2BAR, but a 5′-N-ethylcarboxyamide did not further enhance potency. 2-(3″-(6″-Bromoindolyl)ethyloxy)adenosine 28 displayed an A2BAR EC50 value of 128 nM, that is, more potent than the parent 17 (299 nM) and similar to 5′-N- ethylcarboxamidoadenosine (140 nM). Compound 28 was a full agonist at A 2B and A2AARs and a low efficacy partial agonist at A 1 and A3ARs. Thus, we have identified and optimized 2-(2-arylethyl)oxo moieties in AR agonists that enhance A2BAR potency and selectivity.