From Structure to Function: COX-Selective Anti-Inflammatory Activity of Cu(II) and Zn(II) Hydrazone Complexes.
Ram Nayan Gautam1, Riya Kumari1, Diptee Mitra2
1Department of Chemistry, Banaras Hindu University, Varanasi, India.
Chembiochem : a European Journal of Chemical Biology
|May 10, 2026
Summary
Metal complexes of hydrazone ligands show enhanced anti-inflammatory activity. Copper(II) and Zinc(II) complexes demonstrated significant cyclooxygenase inhibition, with one complex showing potent dual COX-1/COX-2 inhibition and high selectivity.
Area of Science:
- Medicinal Chemistry
- Inorganic Chemistry
- Pharmacology
Background:
- Hydrazone ligands are versatile pharmacophores with tunable properties.
- Metal complexation can modulate ligand characteristics for therapeutic development.
- Metal-based therapeutics offer unique mechanisms for disease treatment.
Purpose of the Study:
- To design, synthesize, and characterize novel hydrazone ligands and their Cu(II) and Zn(II) complexes.
- To evaluate the anti-inflammatory potential of these metal complexes.
- To investigate the structure-activity relationship and mechanism of action.
Main Methods:
- Synthesis and structural characterization (spectroscopic, crystallographic) of ligands and metal complexes.
- In vitro cyclooxygenase (COX) inhibition assays.
- Molecular docking studies to predict binding interactions.
Main Results:
- Tridentate coordination confirmed, forming distorted octahedral metal complexes.
- Metal coordination significantly boosted anti-inflammatory activity compared to free ligands.
- Specific Cu(II) and Zn(II) complexes displayed notable COX-2 selectivity; complex 6 was a potent dual COX-1/COX-2 inhibitor.
Conclusions:
- Metal coordination enhances the enzyme binding affinity and anti-inflammatory efficacy of hydrazone ligands.
- The synthesized Zn(II) complex shows promise as a broad-spectrum anti-inflammatory agent.
- These findings highlight the potential of metal-based compounds in developing novel anti-inflammatory drugs.
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