Copper(II) Complexes with Mixed Heterocycle Ligands as Promising Antibacterial and Antitumor Species

• Main Authors: Arpad Mihai Rostas, Mihaela Badea, Lavinia L. Ruta, Ileana C. Farcasanu, Catalin Maxim, Mariana Carmen Chifiriuc, Marcela Popa, Mirela Luca, Natasa Celan Korosin, Romana Cerc Korosec, Mihaela Bacalum, Mina Raileanu, Rodica Olar
• Format: Article
• Language: English
• Published: MDPI AG 2020-08-01
• Series: Molecules
• Subjects: Copper(II) complex; 1,2,4-triazolo[1,5-<i>a</i>]pyrimidine; Cytotoxicity; Biofilm; Metallonuclease activity; DNA intercalation
• Online Access: https://www.mdpi.com/1420-3049/25/17/3777

Complexes with mixed ligands [Cu(N-N)₂(pmtp)](ClO₄)₂ ((<b>1</b>) N-N: 2,2′-bipyridine; (<b>2</b>) L: 1,10-phenanthroline and pmpt: 5-phenyl-7-methyl-1,2,4-triazolo[1,5-<i>a</i>]pyrimidine) were synthesized and structurally and biologically characterized. Compound (<b>1</b>) crystallizes into space group <i>Pa</i> and (<b>2</b>) in <i>P</i>-1. Both complexes display an intermediate stereochemistry between the two five-coordinated ones. The biological tests indicated that the two compounds exhibited superoxide scavenging capacity, intercalative DNA properties, and metallonuclease activity. Tests on various cell systems indicated that the two complexes neither interfere with the proliferation of <i>Saccharomyces cerevisiae</i> or BJ healthy skin cells, nor cause hemolysis in the active concentration range. Nevertheless, the compounds showed antibacterial potential, with complex (<b>2</b>) being significantly more active than complex (<b>1</b>) against all tested bacterial strains, both in planktonic and biofilm growth state. Both complexes exhibited a very good activity against B16 melanoma cells, with a higher specificity being displayed by compound (<b>1</b>). Taken together, the results indicate that complexes (<b>1</b>) and (<b>2</b>) have specific biological relevance, with potential for the development of antitumor or antimicrobial drugs.