2.3. Molecular docking
Molecular docking simulates the ligand – receptor interactions. It is the most important procedure which helps to assure all estimations are reliable. The docking was repeated several times to prove results are not affected by random. Auto dock 4.2, MOE 2019 and Molegro virtual docker 2013 were used to do the dock. The optimized structure of SARS – COV – 2 spike protein receptor binding domain unit was selected as receptor and the candidate drug was selected as a ligand and all interactions were considered.[11] The results are discussed in results and discussion section.