Antimony complexes with SNN thiosemicarbazones: Synthesis, structural studies and cytotoxicity against bacterial and cancer cells

•Two antimony complexes with tridentate N2S thiosemicarbazones were prepared.•The complexes, in comparison to the ligands and ampicillin, displayed elevated inhibitions in staphylococcus aureus and escherichia coli strains.•The complexes, comparing with the ligands, exhibited higher cytotoxicity towards MCF-7 cells.•This cytotoxicity towards MCF-7 cells is less comparing with that of doxorubicin, but doxorubicin is much more toxic towards normal BHK cells. Addition of antimony(III) chloride to ligands {HL1 = 4-(4-nitrophenyl)-1-((pyridin-2-yl)methylene)thiosemicarbazide and HL2 = 4-(2-methoxyphenyl)-1-((pyridin-2-yl)methylene)thiosemicarbazide} produced the complexes [Sb(L1)Cl2] (C1) and [Sb(L2)Cl2] (C2), respectively. These complexes were formulated based on elemental, spectroscopic and solution conductivity data. X-ray crystallography elucidated the packing of C2 in the triclinic P-1 space group and the exhibition of pseudo octahedral geometry around the antimony cation. The complexes (20 mg/ml) showed the largest inhibition zones in Staphylococcus aureus (34 mm for C1 and 36 mm for C2) and Escherichia coli (33 mm for C1 and 36 mm for C2) strains. HL1 showed no inhibition in the bacterial strains and HL2 inhibited the strains of Staphylococcus aureus and E. coli at 11 and 10 mm, while ampicillin inhibited these strains at 21 and 25 mm, respectively. The ligands' cytotoxic effects were investigated on four human cancer cells and the greatest effect was on the breast MCF-7 cells. The compounds HL1, HL2, C1, C2 and doxorubicin revealed cytotoxicity with IC50 values of 52.4 ± 0.38, 153.7 ± 1.05, 37.5 ± 0.32, 21.8 ± 0.20 and 9.66±0.25 μM in the MCF-7 cancer cells and of 54.8 ± 0.85, 82.7 ± 0.44, 176.5 ± 0.70, 196.7 ± 1.16 and 36.42±0.08 μM in normal baby hamster kidney (BHK) cells.