As the products of the core hopping operation, a total of 500 chemical compounds were prepared with the LigPre module [53] , which consists of the procedures of generating possible states by ionization at target pH 7.062.0, desalting, retaining chiralities from 3D structure and geometry minimization with the OPLS2005 force field [41] . When the above steps were accomplished, all investigated compounds were docked into the receptor pocket through the rigid protein docking model with the Stand-Precision (SP) scoring function [54, 55] to estimate the binding affinities.