New organotin(IV) complexes derived from 1-adamantanethiol: synthesis, crystal structure, DFT calculation, and in vitro antifungal activity and cytotoxicity

Five new organotin(IV) complexes, Me₂SnL₂ (1), n–Bu₂SnL₂ (2), t–Bu₂SnL₂ (3), Ph₂SnL₂ (4), and Ph₃SnL (5), have been designed and synthesized by the reactions of the deprotonated 1-adamantanethiol ligand (L = C₁₀H₁₅S) with the corresponding R₂SnCl₂ (R = Me, n–Bu, t–Bu, Ph) and Ph₃SnCl. The complexes were characterized by elemental analysis, FT-IR, NMR spectroscopy, and X-ray crystallography. Meanwhile, optimized geometrical parameters, harmonic vibrational frequencies, and frontier molecular orbitals were calculated. The in vitro cytotoxicities of the complexes were evaluated with HeLa and HepG-2. Furthermore, the antifungal activity of the newly synthesized complexes has been evaluated, and the SEM and TEM images were prepared from Alternaria kikuchiana Tanaka to analyze the macroscopic action of the drug on the fungus. As a result, complex 5 has good antifungal activity and cytotoxicity.