Potential bioactive Vanillin–Schiff base di- and tri-organotin(IV) complexes of 4-((3,5-dimethylphenylimino)methyl)-2- methoxyphenol: synthesis, characterization and biological screenings

摘要

Eight different di- and triorganotin(IV) complexes of vanillin-Schiff base of the type R_2SnClL and R_3SnL [R = Me (1,6), n-Bu (2,7), Ph (3,8), tert-Bu (4), Cy (5) and L = 4-((3,5-dimethylphenylimino)methyl)-2- methoxyphenol] were synthesized. The products were characterized by elemental analysis, FT-IR, ~1H, ~(13)C and ~(119)Sn NMR spectroscopy. The ligand 4-((3,5-dimethylphenylimino) methyl)-2-methoxyphenol is also characterized by single crystal X-ray analysis. In the ~1H NMR spectra of 1 and 6, the ~2J(~(119/117)Sn-~1H) in the Sn-CH_3 moiety has 57 and 54 Hz values, respectively, that confirm the formation of four-coordinated Sn species. Moreover, the ~(13)C NMR value for ipso carbon of SnPh is 139 ppm which also confirms the formation of four-coordinated Sn species. The title ligand and its complexes were also screened for their biological activities such as interaction with DNA, enzymatic, antimicrobial, cytotoxic and antioxidant activities. The antimicrobial and cytotoxic activities of triorganotin(IV) derivatives are relatively higher than their corresponding diorganotin(IV) analogues due to their greater lipophilicity and permeability through cell membrane.