Copper(II) Complexes of Selected Acylhydrazones as Potential Biological Agents

In the current research a series of new copper(II) complexes with novel acylhydrazone ligands were synthesized and their antibacterial and anticancer activities were determined. The complexes were characterized by molecular spectroscopy (FT-IR and UV-Vis) and conductivity measurements. Additionally, their structure was confirmed by single-crystal X-ray analysis. The crystallographic data revealed that all compounds are mononuclear Cu(II) species. The Cu(II) ion is four-coordinated by the ONO donor set from mono-deprotonated hydrazone ligand and one Cl^¯ anion, forming distorted square-planar geometry. The biological studies revealed that the compounds exhibit high antimicrobial activity, especially against Gram-positive bacteria, in some cases greater than the reference substances, and better activity than free ligands. The tested complexes possessed the lowest MIC and MBC values towards <i>Staphylococcus epidermidis</i> ATCC 12228 and <i>Micrococcus luteus</i> ATCC 10240. Furthermore, they showed no toxicity towards normal cell lines.