New organotin(IV) complexes derived from 1-adamantanethiol: Synthesis, structure, DFT calculation and in vitro bioactivities

Abstract Five new organotin(IV) complexes, Me 2 SnL 2 ( 1 ), n -Bu 2 SnL 2 ( 2 ), t -Bu 2 SnL 2 ( 3 ), Ph 2 SnL 2 ( 4 ), and Ph 3 SnL ( 5 ), have been designed and synthesized by the reactions of the deprotonated 1-adamantanethiol ligand (L = C 10 H 15 S) with the corresponding R 2 SnCl 2 (R = Me, n -Bu, t -Bu, Ph) and Ph 3 SnCl. The newly synthesized complexes have been characterized by elemental analysis, FT-IR, NMR ( 1 H, 13 C and 119 Sn) spectroscopy and X-ray crystallography. Structural analyses of the complexes reveal that the tin atoms of five complexes show tetrahedral structure. Meanwhile, optimized geometrical parameters, harmonic vibrational frequencies, frontier molecular orbitals were obtained with B3LYP method on complexes 1–5 for the further certificate of the measured experimental data to give theoretical support. Furthermore, the in vitro biological activities of complexes 1–5 were assessed with the HeLa (human cervical cancer cell line) and HepG-2 (human liver cancer cell line). For the result, complex 5 exhibited a high in vitro cytostatic activity. Also, the antifungal effects were evaluated, SEM and TEM images were prepared from Alternaria kikuchiana Tanaka to analyze the macroscopic action site of the drug on the fungus.