Molecular Docking Analysis

The chemical structure of the active compound was obtained from the Zinc [23] database (http://zinc15.docking.org) and then imported into AutoDockTools-1.5.6 software to add polar hydrogen, distribute the charge, and set the rotatable bond. The resulting structure was saved in “pdbqt” format. The 3D structure of the protein was retrieved from the Protein Data Bank (PDB, http://www.rcsb.org/) and then inputted into PyMOL (v2.3.0) to remove water molecules, co-crystallized ligands, and ions. The AutoDockTools-1.5.6 software was used to add polar hydrogen and distribute the charge; the resulting structure was saved in “pdbqt” format. Molecular docking analysis was performed using AutoDock Vinna (v1.1.2) software. Affinity reflects the score for molecular docking; a lower score indicates stronger binding affinity. In this study, an affinity of less than −7 kcal/mol was considered to indicate strong binding activity.