Exploring diorganotin(IV) complexes of hydrazone based ligands as multi-target agents: Synthesis, structural characterization, DFT and in vitro biological evaluation

In the present manuscript, sixteen new diorganotin(IV) complexes of the type R2SnL1-4, (where R = -CH3, -C2H5, -C4H9 and -C6H5; H2L1 = N'-(3,5-dibromo-2-hydroxybenzylidene)-2-(naphthalen-2-yl)acetohydrazide, H2L2 = N'-(3-bromo-5-chloro-2-hydroxybenzylidene)-2-(naphthalen-2-yl)acetohydrazide, H2L3 = N'-(2-hydroxy-3methoxy-5-nitrobenzylidene)-2-(naphthalen-2-yl)acetohydrazide, H2L4 = N'-(3-ethoxy-2-hydroxybenzylidene)2-(naphthalen-2-yl)acetohydrazide) have been synthesized and characterized by elemental analysis, FT-IR, NMR (1H, 13C, 119Sn), and mass spectrometry. Spectroscopic outcomes reveals that hydrazone ligands coordinate to tin atom via the imine nitrogen, phenolic oxygen and enolic oxygen. To gain more insights into the molecular structures, DFT calculations were performed to calculate HOMO-LUMO energy gap and Mulliken charges of selected compounds. The in vitro antimicrobial activity of ligands and their corresponding complexes was performed against four bacterial and two fungal strains. Antimicrobial activity results concluded that complexes 8 and 12 were found most potent against E. coli, A. niger and C. albicans strains. In addition to their antimicrobial efficacy, the prepared compounds were also checked for their anticancer activity against three cancer cell lines, namely A549, MCF7, and HCT-116. The results of the anticancer activity highlighted the potential of complexes 10 and 17 as effective candidates against the tested cell lines.