Tin-containing Compounds Research Articles

Abstract 2807: Cytotoxic activity of novel organotin compounds against different cancer cell lines

Abstract Cisplatin has been a successful drug in oncology for decades. Its use is however limited by toxicity and development of resistance. Efforts for improvement by screening a large number of different platinum compounds have only yielded to new drugs to the clinic, oxaloplatin and carboplatin. An alternative approach is therefore to explore the potential of other metal-containing compounds. The toxic properties of organic tin compounds have been exploited in industry for a long time. More recently such compounds have been studied for potential therapeutic cytotoxic effects yielding promising results. Here we describe the first screening of two novel organotin compounds, based on the same basic structure, containing bromide (SNO7) or chloride (SNO8). The compounds are being screened against the following cancer cell lines: T47-D (breast), A549 (lung), OVCAR-3 (ovarian), Aspc-1 (pancreatic). IC50 was determined from survival analysis by Crystal violet, and induction of apoptosis by Annexin V staining, monitored by IncuCyte. Cisplatin was used as reference. IC50 values (µg/ml) for T47-D and Aspc-1 were, respectively: 44.5 and 13.8 (SNO7), 13.4 and 26.3 (SNO8) and 34.9 and 34.5 (Cisplatin). SNO7 induced apoptosis starting after 24 hours in OVCAR-3 and A549 at 10 µg/ml and also T47-D at 25 µg/ml; SNO8 in T47-D at 25 µg/ml (OVCAR-3 and A549 not tested) and Cisplatin in OVCAR-3 at 10 µg/ml (A549 not tested). These early results indicate differences in sensitivities between compounds and cell lines implying some specificity in mode of action and suggest that tin-containing compounds could be active against cancer cells that are resistant to cisplatin. Citation Format: Paulina Cherek, Michaela Balogova, Krishna Damodaran, Helga M. Ögmundsdottir. Cytotoxic activity of novel organotin compounds against different cancer cell lines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2807.

Synthesis of PtRu5(CO)14(PBut3)(μ-H)2(μ6-C) and Its Reactions with Pt(PBut3)2, HGePh3, and HSnPh3

Reaction of PtRu5(CO)15(PBut3)(C), 3, with hydrogen at 97 degrees C yielded the new dihydride-containing cluster compound PtRu5(CO)14(PBut3)(mu-H)2(mu6-C), 5. Compound 5 was characterized crystallographically and was shown to contain an octahedral cluster consisting of one platinum and five ruthenium atoms with a carbido ligand in the center. Two hydrido ligands bridge two oppositely positioned PtRu bonds. Compound 5 reacts with Pt(PBut3)2 to yield Pt2Ru5(CO)14(PBut3)2(mu-H)2(mu6-C), 6, a Pt(PBut3) adduct of 5, by adding a Pt(PBut3) group as a bridge across one of the Ru-Ru bonds in the square base of the Ru5 portion of the cluster. Compound 6 is dynamically active on the NMR time scale by a mechanism that appears to involve a shifting of the Pt(PBut3) group from one Ru-Ru bond to another. Two new complexes, PtRu5(CO)13(PBut3)(mu-H)3(GePh3)(mu5-C), 7, and PtRu5(CO)13(PBut3)(mu-H)2(mu-GePh2)(mu6-C), 8, were obtained from the reaction of 5 with HGePh3. The cluster of 7 has an open structure in which the Pt(PBut3) group bridges an edge of the square base of the square pyramidal Ru5 cluster. Compound 7 also has three bridging hydrido ligands and one terminal GePh3 ligand. When heated to 97 degrees C, 7 is slowly converted to 8 by cleavage of a phenyl group from the GePh3 ligand and elimination of benzene by its combination with one of the hydrido ligands. The PtRu5 metal cluster of 8 has a closed octahedral shape with a GePh2 ligand bridging one of the Ru-Ru bonds. Two tin-containing compounds, PtRu5(CO)13(PBut3)(mu-H)3(SnPh3)(mu5-C), 9, and PtRu5(CO)13(PBut3)(mu-H)2(mu-SnPh2)(mu6-C), 10, which are analogous to 7 and 8 were obtained from the reaction of 5 with HSnPh3.

Inhibition of premixed methane flames by manganese and tin compounds

The first experimental measurements of the influence of manganese- and tin-containing compounds (MMT, TMT) on the burning velocity of methane/air flames are presented. Comparisons with Fe(CO) 5 and CF 3Br demonstrate that manganese and tin-containing compounds are effective inhibitors. The inhibition efficiency of MMT is about a factor of two less than that of iron pentacarbonyl, and that of TMT is about 26 times less effective, although TMT is still about twice as effective as CF 3Br. There exist conditions for which both MMT and TMT show a loss of effectiveness beyond that expected because of radical depletion, and the cause is believed to be particle formation. Kinetic models describing the inhibition mechanisms of manganese- and tin-containing compounds are suggested. Simulations of MMT- and TMT-inhibited flames show reasonable agreement with experimental data. The decomposition of the parent molecule for the tin and manganese species is found to have a small effect on the inhibition properties for the concentrations in this work. The inhibition effect of TMT is determined mostly by the rate of the association reaction H + SnO + M ↔ SnOH + M, and the catalytic recombination cycle is completed by the reactions SnOH + H ↔ SnO + H 2 and SnOH + OH ↔ SnO + H 2O. The inhibition mechanism by manganese-containing compounds includes the reactions: MnO + H 2O ↔ Mn(OH) 2; Mn(OH) 2 + H ↔ MnOH + H 2O, and MnOH + OH (or H) ↔ MnO + H 2O (or H 2), and the burning velocity is most sensitive to the rate of the reaction Mn(OH) 2 + H ↔ MnOH + H 2O.

Synthesis of New Network Phosphates with NZP Structure

New NZP-type phosphates of the formula PbM3+M4+P3O12 (M3+=Cr, Fe, and In; M4+=Ti, Zr, Hf, and Sn) were synthesized. The evolution of lattice parameters with radii of M3+ and M4+ cations indicates the anomalous behavior of tin-containing compounds. The room temperature structure of PbFeZrP3O12 has been refined using powder neutron diffraction data. The compounds were characterized by infrared and electronic spectroscopic methods. Pb0.5Mo2P3O12 with molybdenum present in the reduced state (+4) was synthesized. It is found that Pb0.5Mo2P3O12 is structurally related to TlMo2P3O12 and crystallizes in an orthorhombic system with parameters a= 8.621Å; b=9.492 Å; c=12.486 Å.

Plasma surface modification of propylene‐based polymers by silicon and tin‐containing compounds

AbstractPlasma surface modifications of homo‐, co‐, and terpolymers of propylene films in the presence of selected organosilicon and organotin compounds were investigated. For this, organosilan(stannan)e type compounds (such as vinyltriethoxysilane, 3‐aminopropyltriethoxysilane, and tetraethylstannane) as well as organosiloxan (stannoxan)e type compounds (such as hexamethyldisiloxane and hexabutyldistannoxane) were exployed in plasma. Plasma surface modification of polyolefin films with organosilicon plasma has led to increase of the hydrophobicity, while the presence of organotin compounds in plasma produced less hydrophobic surfaces. Reaction of plasma‐activated polyolefin films further with vinyltriethoxysilane‐maleic anhydride oligomer also led to an increase in the hydrophobicity of polypropylene surfaces. It is observed that the degrees of swelling of (virgin, plasma‐treated, and plasma‐modified) polypropylene films in cyclohexanone strongly depend on the nature of the organoelement compounds used, organosilicon plasma causing lower degrees of swelling. The changes of surface properties observed are explained by different surface structures produced in plasma: in the case of organosilicon compounds, it is believed that poly(organosiloxane) and for organotin compounds poly(organotincarboxylate) fragments are formed primarily. © 1995 John Wiley & Sons, Inc.

RPA MNDO analysis of the dihedral angle dependence of vicinal J(SnSn) and J(SnC) NMR coupling constants

Vicinal J(SnCCSn) and J(SnCCC) spin-spin coupling constants are calculated within the RPA MNDO method for different dihedral angles, θ, determined by the intervening bonds, in model compounds. For both types of couplings, calculated values closely follow Karplus-like dependences. Results are discussed in terms of experimental values, and the effects of substituents attached to the coupled atoms are briefly analyzed for the θ = 0 ° and θ = 180 ° conformations. These last values were also calculated using the RPA AM1 method. Results indicate that the RPA MNDO and RPA AM1 approaches show interesting potential for studying the structural dependences of 3 J(SnSn) and 3 J(SnC) couplings in tin-containing compounds.

Thermooxidative decomposition and combustion of halogen?Tin-containing synthetic fibres

The possibility of decreasing the combustibility of PCA and PETP fibres by treatment with acetone solutions of PVC containing tin oxides or salts was investigated. It was found that the PVC—ZnSn(OH)6 system is the most efficient fire-retardant system for PETP. The oxygen index of PETP after treatment with this system was 27.1%. It was shown that in contrast to other types of halogen—metal-containing fire retardants whose effect is basically manifested in the gas phase, the synergistic system containing PVC and tin-containing compounds changes the direction of the reactions in the condensed phase of combustion. The capacity of the polymer (PCA, PETP) for carbonization increases in the presence of PVC and tin-containing compounds as a result of the formation of thermostable structures characterized by a high concentration of halogen, and the temperature of the onset of oxidation decreases.

Quantitative bioassay using laser-monitored bacteria to assess toxicology and metabolism of bioactive Group IV compounds

A new approach has been developed for assessing the toxicity and the metabolism of Group IV compounds and for other toxic substances that may interact with them at the molecular level. The approach is based upon the selective responses of sensitive biodetectors whose molecular interactions with a wide variety of toxic substances have been previously described and reported. Detection and quantitation of carbon, silicon, and tin-containing compounds has been accomplished using a laser-monitored bacterial bioassay. This system uses isogenic Bacillus subtilis strains that are genetically engineered to respond differentially to specific toxicants. The response of these biodetectors is monitored by differential light scattering of a laser that is integrated with a computerized system which collects and analyzes this data. The assay can routinely generate fully analyzed data for fixed time intervals, i.e. 60 or 90 min, or kinetic data so that the mechanisms of interactions can be elucidated.

Magnetic field dependence of 1H CIDNP in the reaction of trimethyltin hydride with dibenzyl ketone

The magnetic field dependence of 1H CIDNP in the photochemical reaction of trimethyltin hydride enriched by the stable isotope 117Sn in the presence of dibenzyl ketone as initiator has been analysed. Comparing the experimental and simulated 1H CIDNP spectra of benzyltrimethyltin shows that the radical pair mechanism can account for the observed CIDNP effects. The absence of a magnetic isotope effect in reactions of tin-containing compounds is discussed with reference to the obtained 1H CIDNP data.

Photochemical etching during ultraviolet photolytic deposition of metal films on semiconductor surfaces

UV photochemical deposition of Sn films on GaAs (001) surfaces from a variety of tin-containing compounds (tetramethyltin, tetrabutyltin, dibutyltin dibromide, stannic chloride, hexamethylditin, dibutyltin sulfide, and iodotrimethyltin) was studied. X-ray photoelectron spectroscopy showed that during the initial stages of deposition from the halogenated compounds, the GaAs surface was photochemically etched, most likely by a halogen radical species. The photochemical etching resulted in an arsenic deficient surface which was particularly dramatic for the case of SnCl4. These results have important implications for the choice of sources for photochemical deposition when the metal-semiconductor interface is important and for photochemical etching if stoichiometric surfaces are required.

Magnetic double resonance studies of trimethylstannylphosphines and their complexes

The reduced coupling constant 1K(PSn) has substantial negative values in the compounds (Me3Sn)3–nPhnP (n= 0–2) and increases algebraically to values close to zero in transition metal carbonyl complexes (Me3Sn)3–nPhnPM(CO)5(M = Cr, MO, or W). This behaviour parallels that of 1K(PC) in analogous compounds but there is a substantial negative contribution in the tin-containing compounds which is attributed to a larger energy gap between the phosphorus and tin valence atomic orbitals. In contrast with the behaviour of triorganophosphines the phosphorus chemical shifts do not vary linearly with n, and the changes in phosphorus shielding which accompany complex formation are discussed.