New triorganotin(iv) compounds with aromatic carboxylate ligands: synthesis and evaluation of the pro-apoptotic mechanism

Three new organotin(iv) carboxylate compounds were synthesized and structurally characterized by elemental analysis and FT-IR and multinuclear NMR (1H, 13C, 119Sn) spectroscopy. Single X-ray crystallography reveals that compound C2 has a monoclinic crystal system with space group P21/c having distorted bipyramidal geometry defined by C3SnO2. The synthesized compounds were screened for drug-DNA interactions via UV-Vis spectroscopy and cyclic voltammetry showing good activity with high binding constants. Theoretical investigations also support the reactivity of the compounds as depicted from natural bond orbital (NBO) analysis using Gaussian 09. Synthesized compounds were initially evaluated on two cancer (HeLa and MCF-7) cell lines and cytotoxicity to normal cells was evaluated using a non-cancerous (BHK-21) cell line. All the compounds were found to be active, with IC50 values less than that of the standard drug i.e. cisplatin. The cytotoxic effect of the most potent compound C2 was confirmed by LDH cytotoxicity assay and fluorescence imaging after PI staining. Apoptotic features in compound C2 treated cancer cells were visualized after DAPI staining while regulation of apoptosis was observed by reactive oxygen species generation, binding of C2 with DNA, a change in mitochondrial membrane potential and expression of activated caspase-9 and caspase-3 in cancer cells. Results are indicative of activation of the intrinsic pathway of apoptosis in C2 treated cancer cells.

Novel triorganotin complexes based on phosphonic acid ligands: Syntheses, structures and in vitro cytostatic activity

Six novel organotin phosphonate complexes, [(Me₃Sn)₄(HL¹)₄]_n1, [(Me₃Sn)₂(HL²)₂]_n2, [(Me₃Sn)₂L³(H₂O)]_n3, [(Ph₃Sn)(HL¹)]₆4, [(Ph₃Sn)₂L²]_n5 and [(Ph₃Sn)₂L³]₆6, derived from phosphonic acid ligands [NaHL¹ = 1-C₁₀H₇OPO₂(OH)Na, H₂L² = 1-C₁₀H₇PO(OH)₂, H₂L³ = 2-C₁₀H₇PO(OH)₂], have been synthesized and characterized by elemental analysis, FT-IR, NMR (¹H, ¹³C, ³¹P and ¹¹⁹Sn) spectroscopy and X-ray crystallography. The structural analysis reveals that complexes 1 and 5 display 1D infinite zig-zag chain structures, and complex 2 shows 1D right-handed helical chain structure, while complex 3 displays 1D left-handed helical chain structure. Complexes 4 and 6 are 24-membered macrocyclic rings interconnected by P, O and Sn atoms. Additionally, the molecules of complexes 1 and 3 are further linked through intermolecular π···π and O-H···O interaction into supramolecular structures, respectively. Furthermore, we preliminarily estimated in vitro cytostatic activity of complexes 1-6 against the human cervix tumor cells (HeLa), human hepatocellular carcinoma cells (HepG-2) and human normal breast cells (HBL-100). Importantly, the anti-proliferative properties and possible pathway of complex 6 are investigated, and the results demonstrate that complex 6 could induce apoptotic cell death via an overload of intracellular reactive oxygen species (ROS) levels and the dysfunctional depolarization of mitochondrial membranes.

Syntheses, characterization, DNA/BSA binding, and in vitro cytostatic activity of fluorobenzenetelluronic triorganotin(iv) esters

A new series of fluorobenzenetelluronic triorganotin(iv) esters (1–6) have been synthesized by the reaction of deprotonated fluorobenzenetelluronic acid ligands and the corresponding R₃SnCl (R = Me, Ph).

Syntheses, structures and anti-tumor activity of four organotin(iv) dicarboxylates based on (1,3,4-thiadiazole-2,5-diyldithio)diacetic acid

Four novel organotin complexes, derived from flexible (1,3,4-thiadiazole-2,5-diyldithio)diacetic acid (H₂tzda), have been synthesized and characterized by elemental analysis, FT-IR, NMR and X-ray crystallography.

A novel octa-nuclear 32-membered zirconocene macrocycle based on the aromatic selenite

A novel macrocyclic zirconocene(iv) aromatic selenite [(CpZr)₈L₁₆]·2(Cp₄Zr₂(μ-O)Cl₂) (complex 1) (Cp = cyclopentadienyl anion; L = 4-fluorobenzeneseleninic acid) was prepared by the reaction of bis(cyclopentadienyl)zirconium dichloride with 4-fluorobenzeneseleninic acid and characterized by elemental analysis, infrared spectroscopy, ¹H, ¹³C NMR spectroscopy, ESI-MS, XRD and X-ray diffraction.

Novel organotin(iv) complexes derived from 4-fluorophenyl-selenoacetic acid: synthesis, characterization and in vitro cytostatic activity evaluation

A cluster of novel organotin(iv) complexes were designed, synthesized, and characterized by elemental analysis, FT-IR, and NMR (¹H, ¹³C, and ¹¹⁹Sn) spectroscopy as well as single-crystal X-ray diffraction.