Exploring antiviral properties of Favipiravir analogues; A computational approach

The role of repurposed and analogous drug systems has become prominent during the pandemic when the world struggled to synthesize and mobilize novel antiviral medicines in abundance at short notice. There is necessity to develop newer and better antiviral medicines for the future. In this regard, having a digital library of robust small molecules with proven antiviral properties and lesser or minimal toxicity impacts will be highly beneficial. The present study involves two process impurities of Favipiravir, Molecule1 (6-Bromo-3-hydroxy pyrazine-2-carboxamide) and Molecule2 (3-hyroxy pyrazine-2-carboxamide) as possible drug molecules for targeting the MPro of SARS-CoV-2. Studies include geometry optimization, bioavailability and toxicity profiles (ADMET) predictions. The molecules were also subjected to molecular docking against the Main Protease (MPro) of SARS-CoV-2 with binding energy of-3.96 and-4 respectively for molecules Molecule1 and Molecule2. Study on the ligand binding pocket’s surface area, volume and drug score for the protein ligand complex was found to be 842.81 Å2, 702.27 Å3 and 0.77 and 334.84 Å2, 153.86 Å3 and 0.26 respectively. Both the molecules have shown better binding energy and specific binding sites than favipiravir.