Theoretical Evaluation of the Properties of Nitrogen-Doped C24 Fullerenes and Their Interactions with Two Adamantane-Derived Antivirals

Abstract

The replacement of carbon with a heteroatom within the structure of a fullerene gives the possibility of obtaining compounds with adjustable properties. The influence of aza-substitution on C24 fullerenes was investigated and a comparison of HF and DFT calculations was performed. Various substitution patterns were proposed and the characterization of C22N2 and C20N4 structures was performed. Global reactivity descriptors like chemical potential, hardness, HOMO–LUMO gap and singlet–triplet gap were computed. Aromaticity descriptors like delocalization indices and NICS(0) index were employed for the characterization of each six-membered ring of the studied fullerenes. The possible use of aza-fullerenes as drug delivery systems for two adamantane-derived antivirals was evaluated through molecular docking studies. The best results were obtained for the fullerenes with a pronounced hydrophobic character, the favored configuration of the antiviral drugs being the one oriented toward the side consisting of carbon atoms of the fullerenes.