Novel amide-based macrocyclic Co(ii) complexes: correlating structural, computational, and biological properties
Subhash1,2, Manish Kumar3, Vandana2
1Department of Chemistry, Smt. Devkiba Mohansinhji Chauhan College of Commerce and Science, UT of DNH & DD Silvassa 396230 India.
RSC Advances
|January 16, 2026
Summary
New cobalt(ii) complexes with macrocyclic ligands show significant antimicrobial and antioxidant properties. These functionalized complexes offer potential therapeutic applications with selective cytotoxicity.
Area of Science:
- Coordination Chemistry
- Materials Science
- Medicinal Chemistry
Background:
- Macrocyclic ligands are crucial in coordination chemistry, influencing metal complex properties.
- Cobalt(ii) complexes are explored for diverse applications, including biological activities.
- Functionalized ligands can tune the characteristics of metal complexes for specific uses.
Purpose of the Study:
- Synthesize and characterize novel cobalt(ii) complexes with amide-based macrocyclic ligands.
- Investigate the structural, thermal, and electronic properties of the synthesized complexes.
- Evaluate the antimicrobial, antioxidant, and cytotoxic potential of the ligands and their cobalt(ii) complexes.
Main Methods:
- Synthesis of three related macrocyclic ligands (N4O4MacL1-N4O4MacL3) and their Co(ii) complexes.
- Characterization using elemental analysis, FTIR, UV-Vis, NMR, magnetic susceptibility, and powder XRD.
- Thermal analysis (TGA) with Coats-Redfern and Flynn-Wall-Ozawa models, DFT calculations, in vitro antimicrobial assays, DPPH radical scavenging assay, and molecular docking.
Main Results:
- Successful synthesis and characterization of octahedral Co(ii) complexes, confirming monoanionic tetradentate coordination.
- Complex [Co(N4O4MacL3)Cl2] exhibited highest antioxidant activity, while [Co(N4O4MacL2)Cl2] showed promising antimicrobial activity with low cytotoxicity.
- DFT calculations corroborated experimental findings on geometry and electronic structure; molecular docking supported biological activity.
Conclusions:
- Amide-containing macrocyclic ligands and their cobalt(ii) complexes possess significant therapeutic potential.
- The synthesized complexes demonstrate promising antimicrobial efficacy, antioxidant capacity, and selective cytotoxic effects.
- These findings suggest potential applications in antimicrobial therapies and as effective antioxidants.
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