Synthesis, crystal structures, and biological activity of aroylhydrazone di-m-chlorobenzyltin complexes

Abstract

Six aroylhydrazone di-m-chlorobenzyltin complexes {[X-C₆H₄(O)C=N-N=C(Me)COO](MeOH)(m-Cl-C₆H₄CH₂)₂Sn}₂ (X = p-Me- (1), p-MeO- (2), p-t-Bu- (3), p-NO₂- (4), p-OH- (5) or o-OH- (6)) were synthesized and characterized by HRMS (high-resolution mass spectrometry), NMR (nuclear magnetic resonance spectroscopy), IR (Fourier transform infrared spectroscopy), and TGA (thermogravimetric analysis) techniques. The molecular structure of complexes 1-6 was confirmed by single-crystal X-ray crystallography. The structure of complexes showed a distorted pentagonal bipyramidal configuration around the tin atom center, and the ligands adopted a tridentate chelating mode. Fascinatingly, either one-dimensional infinite chain structures or two-dimensional network structures were observed in the complexes through hydrogen bonds. Complex 2 has the strongest inhibitory effect on MCF7 and HepG2 cell proliferation, its effect was superior to that of the positive control drug cisplatin. The interaction of ct-DNA (calf-thymus DNA) with complex 2 was explored using UV absorption (ultraviolet absorption) and fluorescence spectroscopy. Complex 2 exhibited a moderate affinity for ct-DNA through intercalation modes. The interaction of complex 2 with ct-DNA has also been supported by molecular docking studies.

Keywords: Arylformylhydrazone; Biological activity; Crystal structure; Organotin; Synthesis.