A novel dimeric copper(II) complex derived from a Schiff base ligand: Structural insights and antibacterial potential

• DOI: 10.1016/j.poly.2025.117391
• Publication Date: 2025-01-17T00:00:20Z
• Authors: Hamid Zeighami Nejad; S. Yousef Ebrahim...; S. Jamilaldin Fatemi; Hadi Ebrahimnejad; Jesus Castro

A novel copper(II) complex, [Cu(L)(py)], was synthesized utilizing the Schiff base ligand 3-((2-hydroxyphenyl)amino)-1-phenylbut-2-en-1-one-2-ylidene)phenol (HL). The ligand was prepared through the condensation reaction of benzoylacetone and 2-aminophenol. The subsequent copper(II) complex was obtained by reacting the ligand with copper(II) acetate in the presence of pyridine. The structures of the ligand and complex were elucidated by elemental analysis, FT-IR, ¹H NMR spectroscopy, and single-crystal X-ray diffraction. The complex crystallizes in the triclinic system, space group P-1, with two independent molecules within the asymmetric unit. The copper(II) ion adopts a square pyramidal geometry, coordinated by the azomethine nitrogen, two phenolic oxygen atoms, and a pyridine molecule. The Cu-Cu distance within the dimeric complex is 3.1646(9) Å. The antibacterial activity of the synthesized complex was assessed against four bacterial strains: Staphylococcus aureus, Bacillus cereus, Escherichia coli, and Salmonella Typhimurium. The minimum inhibitory concentration (MIC) values were determined using the broth dilution method. The complex displayed moderate antibacterial activity against all tested strains, with MIC values ranging from 16 to 32 μM.