Synthesis of asymmetrical tridendate Schiff bases and metal complexes and investigation of anticarcinogen effects on human colon and cervical cancers

ABSTRACT

The metal complexes of Zn(II), Ni(II), Cu(II) and Pb(II) with asymmetrical Schiff bases were synthesized. The asymmetrical Schiff base was obtained through the condensation of 1,2-phenylenediamine, 4-methyl-1,2-phenylenediamine, 2-hydroxy-1-napthaldehyde and biphenyl-4-carbaldehyde. The new Schiff base ligands (L₁' and L₂') and their metal complexes were characterized by TG/DTG, FT-IR, ¹H-NMR, UV–Vis, ESR, powder XRD, elemental analysis, magnetic moment and fluorescence studies. The powder XRD studies indicate that Co(II) and Cu(II) complexes are amorphous, while Ni(II) and Zn(II) complexes are crystalline. The anticarcinogenic effects of L₁' and L₂' were also investigated against colon (SW-620) and cervical cancer (HeLa) cell lines and compound L₂' was found to possess the highest anticarcinogenic potential, with 16.7 µM and 27.5 µM of IC₅₀ values for HeLa and SW620 cells, respectively.

KEYWORDS:

• Anticancer activity;
• ESR
• metal complexes;
• Schiff base
• XRD

Acknowledgments

The authors are grateful to Dr. Ulku Sayin (Selcuk University, Physics Department) for her efforts in the ESR analyses.

Funding

This study was supported by Selcuk University Research Foundation with project number: 14201023.