RT Journal Article T1 X‐Ray Crystallography and Free Energy Calculations Reveal the Binding Mechanism of A2A Adenosine Receptor Antagonists A1 Jespers, Willem A1 Verdon, Grégory A1 Azuaje Guerrero, Jhonny Alberto A1 Majellaro, María A1 Keränen, Henrik A1 García Mera, Xerardo A1 Congreve, Miles A1 Deflorian, Francesca A1 De Graaf, Chris A1 Zhukov, Andrei A1 Doré, Andrew S. A1 Mason, Jonathan S. A1 Åqvist, Johan A1 Cooke, Robert M. A1 Sotelo Pérez, Eddy A1 Gutiérrez de Terán, Hugo K1 Adenosine receptors K1 Biophysical mapping (BPM) K1 Free energy perturbation (FEP) K1 G protein-coupled receptor (GPCR) AB We present a robust protocol based on iterations of free energy perturbation (FEP) calculations, chemical synthesis, biophysical mapping and X‐ray crystallography to reveal the binding mode of an antagonist series to the A2A adenosine receptor (AR). Eight A2AAR binding site mutations from biophysical mapping experiments were initially analyzed with sidechain FEP simulations, performed on alternate binding modes. The results distinctively supported one binding mode, which was subsequently used to design new chromone derivatives. Their affinities for the A2AAR were experimentally determined and investigated through a cycle of ligand‐FEP calculations, validating the binding orientation of the different chemical substituents proposed. Subsequent X‐ray crystallography of the A2AAR with a low and a high affinity chromone derivative confirmed the predicted binding orientation. The new molecules and structures here reported were driven by free energy calculations, and provide new insights on antagonist binding to the A2AAR, an emerging target in immuno‐oncology PB Wiley SN 1433-7851 YR 2020 FD 2020 LK http://hdl.handle.net/10347/24309 UL http://hdl.handle.net/10347/24309 LA eng NO W. Jespers, G. Verdon, J. Azuaje, M. Majellaro, H. Keränen, X. García-Mera, M. Congreve, F. Deflorian, C. de Graaf, A. Zhukov, A. S. Doré, J. S. Mason, J. Åqvist, R. M. Cooke, E. Sotelo, H. Gutiérrez-de-Terán, Angew. Chem. Int. Ed. 2020, 59, 16536 NO This work was financially supported by the Swedish Research Council (Grant 521‐2014‐2118); Consellería de Cultura, Educación e Ordenación Universitaria of the Galician Government (Grant ED431B2017/70); Centro Singular de Investigación de Galicia accreditation 2016–2019 (Grant ED431G/09), and the European Regional Development Fund (ERDF). Additional support from the Swedish strategic research program eSSENCE is acknowledged. The computations were performed on resources provided by the Swedish National Infrastructure for Computing (SNIC). This research program has been developed in the frame of the European COST action ERNEST (Grant CA 18133) and GLISTEN (Grant CA 1207) DS Minerva RD 30 abr 2026