Bis-substituted diphenylamine arylidene hydrazones for the synthesis of new binuclear organotin(IV) complexes: Crystal structure, DNA cleavage and molecular docking

Abstract

Five dinuclear organotin(IV) complexes, R4Sn2La (R = Me, Ph) and R4Sn2Lb (R = Me, Ph and Bu) have been synthesized from reaction of R2SnCl2 with 2,4′- and 2,2′-bis-substituted diphenylamine arylidene hydrazones, H4La and H4Lb, respectively. The synthesized compounds have been investigated by elemental analysis and IR, 1H NMR, and 119Sn NMR spectroscopy. The structures of Me4Sn2Lb and Ph4Sn2Lb have been also confirmed by X-ray crystallography. The results show that the fully deprotonated bis-hydrazone ligand provides two contiguous ONO tridentate domains that coordinate to the two SnR2 moieties in the enolate form. Each tin atom in the complexes adopts a five-coordinate environment. Ligands and complexes showed no antibacterial activity against Gram-positive (Bacillus subtilis and Staphylococcus aureus) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria. However, both ligands and their methyl complexes were found to degrade DNA, an observation that adapt with the mode of interaction suggested by molecular docking.