Favipiravir: insight into the crystal structure, Hirshfeld surface analysis and computational study

In this work we report structural and computational studies of favipiravir, which is now used as a drug for COVID-19 treatment. The molecule completely flat stabilized by an intramolecular O–H···O hydrogen bond, yielding six-membered pseudo-aromatic ring. aromaticity index ring was found to be 0.748, while the same indix pyrazine in favipiravir 0.954. crystal packing mainly constructed through intermolecular N–H···O, N–H···N C–H···O bonds, 3D supramolecular framework with zst topology defined point symbol (65·8). structure further weak C–F···F–C type II dihalogen interactions, 1D polymeric chain. More than 80% total Hirshfeld surface area occupied H···H/C/N/O/F C···N/O contacts. Energy frameworks have been calculated additionally analyze overall packing. It established that characterized dispersion energy followed less significant electrostatic contribution. Finally, using density functional theory (DFT) calculations quantum atoms molecules, assigned interaction each can helpful develop scoring functions force fields/docking calculations.