Ferrocene amines and ferrocene amides with aliphatic and aromatic moieties as potential antioxidants: DFT calculations and predictions versus natural antioxidants

Abstract

The present comparative study employs the DFT ωb97xD/6–311 + G(d,p) method to assess the antioxidant properties of a wide range of synthetic ferrocene amines and ferrocene amides with aliphatic and aromatic moieties, as well as natural antioxidants (46 compounds in total). Ferrocenes form a large class of organometallics that are readily and reversibly oxidized to stable cation radicals at physiological pH values, making them excellent free-radical scavengers. Density functional theory calculations were performed to define (or predict) the antioxidant potential of these compounds in comparison to natural antioxidants, including vitamins A, E, ascorbic acid, glutathione, etс. A DFT analysis of more than two dozen ferrocene-based compounds has revealed that the most active are ferrocene-based hydrazides and corresponding ferrocene amines, which can potentially exhibit antioxidant potential comparable to that of the natural antioxidants mentioned above. This DFT-based approach permits the prediction of the active compounds` structures, which can then be synthesized for subsequent biological research and investigation. Furthermore, this theoretical investigation has been conducted with the aim of acquiring a more profound comprehension of the fundamental principles underlying antioxidant activity. In the Introduction section a short excurse on antioxidants ferrocene area is presented.