Novel mixed-ligand metal complexes containing anisic acid/nicotinamide ligands. Their synthesis, structural characterization and biological applications

In this study, five different p-methoxybenzoate (anisate)-nicotinamide complex compounds, whose central atoms are transition metal cations (Mn²⁺, Co²⁺, Ni²⁺, Cu²⁺ and Zn²⁺), were synthesized and their structural characterizations were investigated. In addition, the antibacterial and antifungal properties of the compounds against various biological derivatives were investigated by disk diffusion method. Elemental analysis, magnetic susceptibility, FTIR spectra, thermoanalytical TG-DTG/DTA analysis and single crystal X-ray diffraction methods were used to determine the structural characterizations of the compounds. It was determined that the complexes containing Co²⁺ and Ni²⁺ cations, whose single crystal structures were solved, were isostructured. It was suggested that the coordination properties of the other three coordination compounds centered on Mn²⁺, Cu²⁺ and Zn²⁺ were like the solved structures because of the similarity of thermal and spectroscopic analysis results. Due to the nature of the metal cation, it was predicted that only the Cu²⁺ complex was in fivefold coordination and the coordination was completed with two anisate anions, two neutral nicotinamide ligands and one crystal water. It was determined that the other four complex structures were in sixfold coordination and that they completed their coordination with one more crystal water, unlike the Cu²⁺ complex. It was also seen that the complex with the Co²⁺ central atom contained two hydrate waters, unlike the other complexes. The presence of water molecules in the coordination compounds and the thermal decomposition steps of the structures were determined by TG/DTA curves.