Conformational sampling. The eABF method combined with Metadynamics sampling with a single collective variable; the radius of gyration (RDGYR) as implemented in the Colvars module is used to drive the exploration of the conformational landscape of the molecules in vacuum. All ligand atoms are included in the RDGYR collective variable. The calculation is divided into 12 windows (0.5 Å width), spanning from 3 to 9 Å. A M-eABF simulation is run for 2 ns, and 2500 frames equally spaced in time are stored per window, yielding a total of 24 ns of simulation and a maximum of 30000 structures for further analysis. Harmonic walls with a force constant of 10 kcal/mol are used to softly restrain the exploration of the molecule within each window. Both the bin width and the standard deviation between the collective variable and the extended degree of freedom (extendedFluctuation parameter), are set to 0.05 Å, and at least 250 samples must be reached in a bin prior to fully applying the bias (FullSamples parameter) in the ABF calculation. The Gaussian hill´s weight is set to 3.0 kcal/mol and the Gaussian hill width is set to 3.0 Å, while a new Gaussian hill is added every 50 steps to the metadynamics potential. Note that these settings have not been tuned for accurate energy estimation, but to force extensive exploration of the conformational space of the studied molecules in a short simulation time. The integration time for each step of the simulation is 1 femtosecond. Template files for minimization and sampling are available at GitHub: (refer to the Data and Software Availability section).