Comprehensive density functional theory studies on Kojic acid derivatives: NBO, basicity, aromaticity and antioxidant investigations

Abstract

The 4-pyrone scaffold inherent in Kojic acid demonstrates substantive biological attributes. This present inquiry delves into the structural and electronic characteristics of twelve Kojic acid derivatives employing the DFT/B3LYP 6–311++G(d, p) methodology, scrutinizing their behavior in the gas phase and water. Aromaticity indices reveal the aromatic nature of the six-membered rings within the conjugated acids of these compounds. Notably, compound 10, housing an imine group, exhibits heightened basicity surpassing that of 1,8-bis(dimethylamino)naphthalene, potentially categorizing it as a superbase. The assessment of antioxidant activity encompasses both hydrogen atom transfer and single electron transfer-proton transfer mechanisms, revealing a discernible impact of X and Y heteroatoms on the antioxidant activity of structures 1–12.