Areias, FilipeCorreia, CarlaRocha, AshlyTeixeira, SofiaCastro Pérez, MariánBrea Floriani, José ManuelHu, HuabinCarlsson, JensLoza García, María IsabelProença, M. FernandaCarvalho, M. Alice2026-01-292026-01-292024-05-28Areias, F., Correia, C., Rocha, A., Teixeira, S., Castro, M., Brea, J., Hu, H., Carlsson, J., Loza, M. I., Proença, M. F., & Carvalho, M. A. (2024). 2-Aryladenine Derivatives as a Potent Scaffold for Adenosine Receptor Antagonists: The 6-Morpholino Derivatives. Molecules, 29(11), 2543. https://doi.org/10.3390/molecules29112543https://hdl.handle.net/10347/45595A set of 2-aryl-9-H or methyl-6-morpholinopurine derivatives were synthesized and assayed through radioligand binding tests at human A1, A2A, A2B, and A3 adenosine receptor subtypes. Eleven purines showed potent antagonism at A1, A3, dual A1/A2A, A1/A2B, or A1/A3 adenosine receptors. Additionally, three compounds showed high affinity without selectivity for any specific adenosine receptor. The structure-activity relationships were made for this group of new compounds. The 9-methylpurine derivatives were generally less potent but more selective, and the 9H-purine derivatives were more potent but less selective. These compounds can be an important source of new biochemical tools and/or pharmacological drugseng© 2024 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/)Attribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/G protein-coupled receptorsAdenine derivativesAdenosine receptor antagonists2-arylpurine derivativesStructure-activity relationshipjournal article10.3390/molecules291125431420-3049open access