Searching potential antiviral candidates for the treatment of the 2019 novel coronavirus based on DFT calculations and molecular docking.

In the present work, the succinic acid (SA), L-pyroglutamic acid (L-PGA), N-phenyl-thioacetamide (N-NPTA), 2-amino-5-chloropyridine hydrogen succinate (ACPS), epigallocatechine Gallate (EGCG) or KDH and, selenomethionine (SeM) compounds have been proposed as potential antiviral candidates to treatment of COVID-19 based on B3LYP/6-311++G∗∗ calculations and molecular docking. Solvation energies, stabilization energies, topological properties have been evaluated as function of acceptors and donors groups present in their structures. ACPS presents the higher reactivity in solution possibly because has the higher nucleophilicity and elecrophilicity indexes while KDH evidence the higher solvation energy probably due to the higher quantity of donors and acceptors groups. NBO studies show that KDH is the most stable in solution. Mapped MEP surfaces have evidenced stronger nucleophilic and electrophilic sites in ACPS, in agreement with the three C=O and two N-H and O-H groups present in this species while KDH has only a C=O group but a total of 19 acceptors and donors groups. From the above studies for six species we can propose that the better potential antiviral candidate to treatment of COVID-19 is ACPS and then, KDH. For a better prediction of the antiviral and anti-inflammatory properties of the proposed compounds, molecular docking calculations were performed by using four structures of COVID-19. Docking results were discussed basing on binding affinities and the interaction types among ligands and different amino acid residues, indicating the powerful ability of KDH and then ACPS ligands on front of the novel coronavirus disease especially for the first and the fourth species (6LU7, 7BTF).