Favipiravir: Structural Analysis and Activity against COVID-19

Within this work, we have performed an in silico research for structural analysis of Favipiravir and its activity against COVID-19. To this aim, tautomers formations of Favipiravir have been first examined and found that four tautomeric structures could be considered as ligands obtained by density functional theory (DFT) calculations. The related protease and polymerase macromolecules to COVID-19 have been assigned as targets to examine the activity of ligands by Molecular Docking simulations. The results indicated that each of four ligands could interact with each of targets with different properties. F3 is the most stable tautomer and F1 is most active ligand against macromolecules. It has been found that the activity of ligands are more favorable for protease than polymerase target, but the ligand…target interacting complexes are not so much strong regarding low values of binding energies. Qualitative representations of ligand…target interactions also indicated different environments of interaction for complex formations. It is noted that further investigations are still required to examine the dominant activity of Favipiravir against COVID-19.