Syntheses, crystal structures, antitumor and antioxidant activities of two hydrazide–hydrazone-based transition metal complexes

Abstract

Two isostructural hydrazide–hydrazone-based complexes, namely [Zn(L)(HL)(ClO4)]·H2O and [Ni(L)(HL)(ClO4)]·H2O (HL = 2-acetylpyridine isonicotinohydrazone), have been obtained and characterized by physicochemical and spectroscopic methods. In each complex, the first ligand is in the neutral keto form, while the second is in the deprotonated monoanionic enolate form. Both complexes have excellent antitumor activity toward A549 human lung cancer, and BGC823 and SGC7901 human gastric cancer cell lines. Furthermore, both complexes are active scavengers for O 2 −· and OH·, exerting superior activities compared to the free ligand.