Synthesis, Characterization, and Biological Activity of Six Di-p-chlorobenzyltin Complexes Derived from ONO Tridentate Ligands

Six new di-p-chlorobenzyltin complexes {[X-C6H4(O)C=N-N=C(Me)COO](MeOH)(p-Cl-C6H4CH2)2Sn}2 (X= 2-OH- (C1), 4-OH- (C2), 4-NO2- (C3), 4-t-Bu-(C4), 4-MeO-(C5) or 4-Me- (C6)) were synthesized by the reactions of substituted arylhydrazides, sodium pyruvate, and di(p-chlorobenzyl)tin dichloride. All the complexes were characterized by IR, 1H, 13C, 119Sn NMR spectra, HRMS, X-ray single crystal diffraction, and TGA. The complexes (C1∼C6) were screened for their in vitro anticancer activity against MCF-7, HepG2, and NCI-H460 cancer cell lines. In those complexes, complex C2 showed promising anticancer activity. The interaction between C2 and calf thymus DNA was studied by UV absorption and fluorescence spectroscopy. The results showed that the interaction between the complex C2 and DNA was intercalation. Molecular docking was also performed to verify the binding specificity of the complex C2 with DNA.