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Updated: Jul 16, 2026

Determining the Serum Stability of Human Adenosine Deaminase 1 Enzyme
Published on: September 27, 2024
N6-methoxy-2-alkynyladenosine derivatives as highly potent and selective ligands at the human A3 adenosine receptor
Rosaria Volpini1, Diego Dal Ben, Catia Lambertucci
1Dipartimento di Scienze Chimiche, Università di Camerino, Via S. Agostino, 1, 62032 Camerino, Italy.
Abstract:
A new series of N6-methoxy-2-(ar)alkynyladenosine derivatives has been synthesized and tested at the human recombinant adenosine receptors. Binding studies demonstrated that the new compounds possess high affinity and selectivity for the A3 subtype. Among them, compounds bearing an N-methylcarboxamido substituent in the 4'-position showed the highest A3 affinity and selectivity. In particular, the N6-methoxy-2-p-acetylphenylethynylMECA (40; Ki A3 = 2.5 nM, A3 selectivity versus A1 = 21 500 and A2A = 4200) results in one of the most potent and selective agonists at the human A3 adenosine receptor reported so far. Furthermore, functional assay, performed with selected new compounds, revealed that the presence of an alkylcarboxamido group in the 4'-position seems to be essential to obtain full agonists at the A3 subtype. Finally, results of molecular docking analysis were in agreement with binding and functional data and could explain the high affinity and potency of the new compounds.
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