Designed Synthesis of Amino-Azo-Quinoline and Their Nickel(II) Complexes: Molecular Structure, Electrochemistry and an Insight Into Their In Vitro Anti-Cancer Activities

Chem Biodivers. 2025 Jun;22(6):e202402436. doi: 10.1002/cbdv.202402436. Epub 2025 Jan 30.

Abstract

Amino-quinolines are potential candidates that may provide some insight into the current chemotherapeutic research due to their demonstrated anti-cancer activity. This led us to synthesize and explore a new amino-azo-quinoline ligand H2L 1 and its square planar nickel(II) complexes [Ni(HL) (OAc)], 2 and [Ni(HL)Cl], 3 and the structures were determined by Single Crystal X-Ray Diffraction. Theoretical investigation of redox orbitals of the complexes discloses that the reduction process is due to ligand reduction whereas both metal and ligand are contributing towards oxidation. The anti-cancer properties of the ligand and one of the nickel(II) complexes have been assessed by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay, cell migration along with the generation of reactive oxygen species using human epithelial cancer cell line cells. The ligand 1 and complex 3 have been found to show effective anti-cancer activity and for the latter, it is more promising. This may be ascribed to the rigid and robust nature of square planar complex 3, which supports stronger binding with DNA than that of free ligands, possibly due to the flexible nature of the latter. This result has also been validated by molecular docking using nine conformers of the ligand and complex 3 via interaction with B-DNA (PDB ID: 1BNA) where the binding affinity with the complex has been found to be stronger.

Keywords: DFT study; Molecular Docking study; X‐ray crystallography; anti‐cancer activity; coordination chemistry.

MeSH terms

  • Antineoplastic Agents* / chemical synthesis
  • Antineoplastic Agents* / chemistry
  • Antineoplastic Agents* / pharmacology
  • Cell Line, Tumor
  • Cell Movement / drug effects
  • Cell Proliferation / drug effects
  • Coordination Complexes* / chemical synthesis
  • Coordination Complexes* / chemistry
  • Coordination Complexes* / pharmacology
  • Crystallography, X-Ray
  • Dose-Response Relationship, Drug
  • Drug Design*
  • Drug Screening Assays, Antitumor
  • Humans
  • Ligands
  • Models, Molecular
  • Molecular Structure
  • Nickel* / chemistry
  • Nickel* / pharmacology
  • Quinolines* / chemical synthesis
  • Quinolines* / chemistry
  • Quinolines* / pharmacology
  • Reactive Oxygen Species / metabolism
  • Structure-Activity Relationship

Substances

  • Nickel
  • Antineoplastic Agents
  • Coordination Complexes
  • Quinolines
  • Reactive Oxygen Species
  • Ligands