Synthesis, characterization, semi-empirical study, and biological activities of organotin(IV) and transition metal complexes with o-methyl carbonodithioate

Abstract

Three transition metal and six organotin(IV) complexes have been synthesized by treating potassium o-methyl carbonodithioate with ZnCl₂/CdCl₂/HgCl₂ and R₂SnCl₂/R₃SnCl under stirring. The complexes were characterized by IR, ¹H, and ¹³C NMR spectroscopies. IR results show that the ligand is bidentate in 1–3 while monodentate in 4–9, which is also confirmed by semi-empirical study. NMR data reveal four-coordinate geometry in solution. HOMO–LUMO study shows that 7 and 9 are thermodynamically unstable. The enzyme inhibition study shows that 1 is a potent inhibitor of ALP, EC 3.1.3.1, resulting in very slow rate of formation and breakdown of enzyme–substrate complex. UV/visible spectroscopy was used to assess the mode of interaction and binding of the complexes with DNA which shows that 9 exhibits higher binding constant when compared to 6. In protein kinase inhibition assay, 1 was active, while antifungal activity shows that organotin(IV) complexes are more active than transition metal complexes.

Graphical Abstract

Keywords:

• o-Methyl carbonodithioate
• Transition metal complexes
• Organotin(IV)
• IR
• NMR
• Semi-empirical study
• HOMO–LUMO calculations
• Enzyme inhibition study
• DNA interaction
• Antifungal activity

Acknowledgements

QAU is acknowledged for the financial support as URF. SKS and KQ thank the Head, Applied Science and Dean FET, MITS for encouragement and support.