Bleomycin‐dependent DNA damage, erythrocyte hemolysis, antitumor MTT assay, and antimicrobial activity studies for Cd (II), Mn (II), Zn (II), Cr (III), and Fe (III) complexes of a multidentate carbohydrazone ligand

Cd (II), Mn (II), Zn (II), Cr (III), and Fe (III) complexes of a carbohydrazone ligand H4EBC, prepared by the reaction of ethyl acetate and carbohydrazide, have been prepared and fully characterized. The ligand H4EBC acted as a bidentate carbohydrazone with Cd (II) and coordinated through the nitrogen of both (‐NH) and (C=N)azomethine groups, while with Mn (II) and Zn (II), it acted as a neutral NN bidentate ligand. In complexes with Fe (III) and Cr (III), H4EBC acts a bi‐negative tetra‐dentate, coordinating through the oxygen atoms of both enolized (C=O)ester groups and the nitrogen of both (C=N)azomethine groups. To illustrate the proposed geometries and chemical reactivity of the compounds, we employed DFT calculations. Additionally, thermal studies provided insights into the stability of the isolated compounds. Interestingly, the prepared complexes demonstrated emission broad bands at various wavelengths, indicating ligand to metal charge transfer. Based on the inhibition of DNA destruction, the complexes can be ranked in the following order: [Cd(H4EBC)Cl2].2H2O] (1) > H4EBC > [Mn(H4EBC)Cl2)].(H2O)2] (2) > [Zn(H4EBC)Cl2].2H2O] (3) > [Fe(H2EBC)Cl(H2O)].H2O (5) > [Cr(H2EBC)Cl (H2O)].H2O (4). Regarding erythrocyte hemolysis, the order of effectiveness can be arranged as follows: (2) > (1) > H4EBC > (5) > (3) > (4). We further investigated the compounds for their potential in antitumor activity against two cell lines and antimicrobial behavior. Cd(II), Mn(II), Zn(II), Cr(III), and Fe(III) complexes of a carbohydrazone, prepared by the reaction of ethyl acetate and carbohydrazide, have been prepared and fully characterized. We investigated these compounds for their potential in bleomycin‐dependent DNA damage, antioxidant activity using erythrocyte hemolysis, antitumor activity against two cell lines, and antimicrobial behavior.