Exploiting Modeling Studies for Evaluating the Potential Antiviral Activities of some Clinically Approved Drugs and Herbal Materials Against SARS-CoV-2: Towards Hindering the Virus and Blocking the Human Cellular Receptor

Here, we theoretically modeled the binding interaction of the Sars-CoV2 (Spike protein) utilizing molecular docking with some potential repurposed antiviral medications and two botanical products (Curcumin and Quercetin). Molecular docking between the drugs and the Sars-CoV2 proteins reflecting the pure electrostatic forces and H-bond formation is complemented with the DFT results that shed light on the electronic nature of the interactions. Moreover, DFT computations provide invaluable information about the drug reactivity indices calculated from the energies of the frontier orbitals. The DFT results indicate intermolecular electron donor-acceptor interaction besides the H-bond formation. Most of the considered medication molecules act as electron-sink candidates except EIDD-2801, the electron donor. The theoretical results show the high possibility of blocking the human cellular entry against Sare-Cov2 or weakening Sars-Cov2 activity due to the electronic donor-acceptor interactions. The findings are solely computational analysis and need to be corroborated by additional studies.