Cobalt(II) Complexes of 4′-Bromo-Fenamic Acid: Antioxidant Properties, Antibacterial Activity, and Interaction with DNA and Albumins

Author(s): Georgios Malis, Christina N. Banti, Alexia Tialiou, Michael R. Reithofer, Antonios G. Hatzidimitriou, Sotiris K. Hadjikakou, Konstantina C. Fylaktakidou, George Psomas
Abstract: The reaction of 4′–bromo-fenamic acid, a bromo-derivative of fenamic acid (the scaffold of the fenamate non-steroidal anti-inflammatory drugs), with Co(II) in the absence or presence of various nitrogen-donor ligands yielded nine novel, neutral mononuclear Co(II) complexes. These complexes were characterized by physicochemical and spectroscopic techniques and single-crystal X-ray crystallography. The biological evaluation of the compounds focused on their antioxidant and antimicrobial efficacy, as well as their interaction with calf-thymus DNA, pBR322 plasmid DNA (in the absence or presence of diverse irradiations) and serum albumins. The complexes have shown significant antioxidant activity since they can scavenge 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radicals (up to 96.48 ± 0.07%) and reduce H₂O₂ (up to 96.93 ± 0.53%). Antimicrobial testing revealed that the complexes were more active than free 4′-bromo-fenamic acid with four of them classified as bactericidal agents against selected bacterial strains. The compounds can interact with calf-thymus DNA via intercalation, and the calculated DNA-binding constants are on the 10⁶ M⁻¹ order. The plasmid DNA-cleavage ability of the compounds is strongly enhanced under UVA irradiation (photocleavage > 90%). In addition, the compounds can bind tightly and reversibly to serum albumins with binding constants in the 10⁵ M⁻¹ range.
Organisation(s): Department of Inorganic Chemistry
External organisation(s): Aristotle University of Thessaloniki, University of Ioannina, Vienna Doctoral School in Chemistry (DoSChem)
Journal: International Journal of Molecular Sciences
Volume: 26
ISSN: 1661-6596
DOI: https://doi.org/10.3390/ijms26199787
Publication date: 10-2025
Peer reviewed: Yes
Austrian Fields of Science 2012: 104003 Inorganic chemistry, 106023 Molecular biology, 301303 Medical biochemistry
Keywords
ASJC Scopus subject areas: Catalysis, Molecular Biology, Computer Science Applications, Spectroscopy, Physical and Theoretical Chemistry, Organic Chemistry, Inorganic Chemistry
Portal url: https://ucrisportal.univie.ac.at/en/publications/012096ae-c1dd-4ca9-a6ca-acc0584c88ce