Synthesis, crystal structures and spectroscopic properties of two new organotin (IV) complexes and their antiproliferative effect against cancerous and non-cancerous cells

Design and In Vitro Biological Evaluation of a Novel Organotin(IV) Complex with 1-(4-Carboxyphenyl)-3-ethyl-3-methylpyrrolidine-2,5-dione

A novel triphenyltin(IV) compound with 1-(4-carboxyphenyl)-3-ethyl-3-methylpyrrolidine-2,5-dione was synthesized and characterized by IR, NMR spectroscopy, mass spectrometry, and elemental analysis. In vitro anticancer activity of ligand precursor and synthesized organotin(IV) compound was determined against tumor cell lines: human adenocarcinoma (HeLa), human myelogenous leukemia (K562), and human breast cancer (MDA-MB-453), using microculture tetrazolium test (MTT) assay. The results indicate that complex exhibited very high antiproliferative activity against all tested cell lines with IC50 values in the range of 0.22 to 0.53 µM. The highest activity organotin(IV) compound expressed against the HeLa cells (IC50 = 0.22 ± 0.04 µM). The ligand precursor did not show anticancer activity (IC50 > 200 µM). Furthermore, fluorescence microscopy analysis of HeLa cells reveal that organotin(IV) complex induced apoptosis as a mode of cell death, which is consistent with the increase of cells in the sub-G1 phase.

Triphenyltin recognition by primary structures of effector proteins and the protein network of Bacillus thuringiensis during the triphenyltin degradation process

Herein, triphenyltin (TPT) biodegradation efficiency and its transformation pathway have been elucidated. To better understand the molecular mechanism of TPT degradation, the interactions between amino acids, primary structures, and quaternary conformations of effector proteins and TPT were studied. The results verified that TPT recognition and binding depended on amino acid sequences but not on secondary, tertiary or quaternary protein structure. During this process, TPT could change the molecular weight and isoelectric point of effector proteins, induce their methylation or demethylation, and alter their conformation. The effector proteins, alkyl hydroperoxide reductase and acetyl-CoA acetyltransferase, recognizing TPT were crucial to TPT degradation. Electron transfer flavoprotein subunit alpha, phosphoenolpyruvate carboxykinase, aconitate hydratase, branched-chain alpha-keto acid dehydrogenase E1 component, biotin carboxylase and superoxide dismutase were related to energy and carbon metabolism, which was consistent with the results in vivo. The current findings develop a new approach for investigating the interactions between proteins and target compounds.

Crystal structure of bis-(benzoato-κO)di-butyl-tin(IV), nBu2Sn(bzo)2

The title compound, [Sn(C4H9)2(C6H5COO)2], was synthesized in order to study the inter-action between di-n-butyl-tin(IV) oxide and some carb-oxy-lic acids. Di-n-butyl-tin(IV) dibenzoate, nBu2Sn(obz)2, exhibits the same structural features as other diorganotin(IV) dibenzoates characterized by an unsymmetrical bidentate bonding mode [Δ(Sn-O) ≃ 0.4 Å] of the two benzoate groups to tin. In a first approximation, the coordination sphere at tin resulting from the two stronger bonded O atoms [2.1227 (17) and 2.1405 (16) Å] and the two α-C atoms of the n-butyl groups [2.125 (3) and 2.129 (2) Å] is compressed to a tetra-gonal disphenoid [〈(C-Sn-C) = 148.2 (1)° and 〈(O-Sn-O) = 82.01 (6)°]. This coordination sphere is expanded by the less strongly bonded two O atoms [2.507 (2) and 2.485 (2) Å] to a substanti-ally distorted octa-hedron and by a weak inter-molecular Sn⋯O inter-action [2.943 (2) Å] to a penta-gonal bipyramid with the formation of centrosymmetric dimers. The unbranched butyl groups adopt two different conformations: anti-gauche [torsion angles: 166.0 (2)-63.9 (4)°] and gauche-gauche [65.0 (3)-56.3 (3)°]. Inter-molecular inter-actions between the dimers are restricted to O⋯H-C contacts (2.64 Å) and van der Waals inter-actions.