New organotin(IV) complexes with a bis-acyl-hydrazone ligand: Synthesis, crystal structure and immobilization on magnetic mesoporous silica nanoparticles as a strategy in cancer therapy

Abstract

The new binuclear organotin(IV) complexes, (Me2Sn)2L (1) and (Ph2Sn)2L (2), have been synthesized from reaction of R2SnCl2 (R = Me or Ph) with bis(2-hydroxy-1-naphthaldehyde) Succinic dihydrazone (H4L). The synthesized compounds have been characterized by elemental analysis and IR, 1H NMR, and 119Sn NMR spectroscopy. The structures of 1 have been also determined by X-ray crystallography. Both complexes are binuclear with bis-hydrazone coordinated via enolic and phenolic oxygens and imine nitrogen in two tridentate ONO domains. Dihydrazone ligand and its diphenyltin(IV) complex were also chemically immobalized on functionalized magnetic mesoporous silica nanoparticles. The new organic-inorganic hybrid nanocomposites were characterized by FT‐IR, PXRD, BET, TGA, VSM, FE‐SEM, HRTEM and EDX techniques. Then, the in vitro cytotoxicity of the synthesized compounds against A549 cancer cell lines was evaluated. Diphenyltin(IV)-loaded magnetic mesoporous silica nanoparticles, Fe3O4@mSiO2-SnPh2, displayed the highest cytotoxic activity compared to other nanoparticles and also was able to reduce the cell viability in a more efficient manner in comparison with the free (Ph2Sn)2L. The inverted microscopy morphology and acridine orange staining indicate that A549 cells progress to cell death after being treated with Fe3O4@mSiO2-SnPh2 nanoparticles.