In silico screening of some naturally occurring bioactive compounds predicts potential inhibitors against SARS-COV-2 (COVID-19) protease

Abstract

The reports pertaining to the mitigation and treatment of the COVID-19 pandemic are still lacking. Compatibility of the natural products and availability of the modern computational techniques motivated us to carry out In Silico investigations on some bioactive natural compounds reportedly found in the fruits and leaves of Anthocephalus Cadamba commonly known as Kadam or Kadamb Tree, aiming to predict the potential inhibitors against the aforesaid virus. Having modeled the ground state ligand structure of the nine natural compounds applying density functional theory at B3LYP/631+G (d, p) level, we have performed their molecular docking with SARS-COV-2 protease to calculate the binding affinity as well as to screen the binding at S-protein site during ligand-protein interactions. Out of these nine studied naturally occurring compounds; Oleanic Acid has been appeared to be a potential inhibitor for COVID-19 followed by Ursolic Acid, Iso-Vallesiachotamine, Vallesiachotamine, Cadambine, Vincosamide-N-Oxide, Isodihydroamino-cadambine, Pentyle Ester of Chlorogenic Acid and D-Myo-Inositol. Hence, these bioactive natural compounds or their structural analogs may be explored as an anti-COVID-19 drug agents. The solubility and solvent-effect related to the phytochemicals may be the point of concern. In vivo investigations on these proposed natural compounds or their structural analogs are invited for designing and developing the potential medicine/vaccine for the treatment of COVID-19 pandemic.