The analysis of volatile trace compounds in landfill gases,compost heaps and forest air

Landfill gas, cryotrapped on a loop fashioned from a length of a capillary gas chromatography (GC) column, was examined for volatile organometallic compounds (VOMCs) and for volatile organic compounds (VOCs) by using GC–mass spectrometry (MS). A large number of organic components were present and many were identified, but the only VOMCs present in high enough concentrations to be detected were trimethylstibine and tetramethyltin. The use of inductively coupled plasma (ICP)‐MS as an element‐specific detector allowed the identification of a number of other organometallic species in the landfill gas, including trimethylarsine and trimethylbismuth, and, for the first time, butyltrimethyltin and dibutyldimethyltin. The presence of molybdenum hexacarbonyl was confirmed. Gas from a large‐scale compost heap and from compost incubated in the laboratory contained iodomethane but no common VOMCs (GC–ICP‐MS). Only VOCs were present in forest air (GC–MS). Copyright © 2003 John Wiley & Sons, Ltd.     

Effects of tributyltin(IV) chloride on the gametes and fertilization of Ascidia malaca (Ascidiacea: Tunicata)

Ascidia malaca gametes before fertilization incubated in 10^?5 or 10^?7 M solutions of tributyltin(IV) chloride, TBTCl, for 3 h appear highly damaged under transmission electron microscopy observation. Also, the fertilization process is affected by the compound: the damaged spermatozoa are present in the vitelline coat and the egg does not cleave. An increase of microbodies, structurally similar to peroxisomes, have been detected in the egg peripheral cytoplasm, probably in relation to their role in alleviating damage to some cellular components. The results have shown that the reproduction of ascidians under unfavourable environmental conditions is prevented. Copyright © 2003 John Wiley & Sons, Ltd.     

Organometallic complexes with biological molecues,part 3. in vivo cytotoxicity of diorganotin (IV) chloro and triorganotin (IV) chloro derivatives of penicillin g on chromosomes of aphanius fasciatus (pisces,cyprinodontiformes)

In order to obtain a continuous source of mitotic metaphases, gill tissue of Aphaius fasciatus (Pisces, Cyprinodontiformes) has been successfully employed. Results gathered after exposure of fish to R₂SnClpenG, R₃SnClpenGNa, to the parents R₂SnCl₂, R₃SnCl and to penGNa (penGNa = penicillinGNa; R = methyl, butyl and phenyl) suggest that both the parent organotin (IV) chloride and organotin (IV) chloropenG derivatives are toxic while penGNa exerts no significant toxic activity. Essentially, all of the chromosome abnormalities are classifiable as irregularly staining of chromosomes, breakages, side-arm bridges or pseudochiasmata.     

Breakage of λ-DNA by inorganic tin and organotin compounds as environmental pollutants

In proportion to the environmental pollution problems caused by organotin compounds, the genotoxicities of tin compounds in the environments have become of interest so as to estimate their safety in recent years. In this work, isolated λ-DNA (double-strand DNA) was incubated with inorganic tin(II) and tin(IV) and five organotin compounds [n-butyltin trichloride, di(n-butyltin) dichloride, methyltin trichloride, dimethyltin dichloride and trimethyltin chloride] in reaction systems both with and without hydrogen peroxide (H₂O₂) content. The tin compounds tested in this study did not induce DNA breakage in the absence of hydrogen peroxide. Divalent inorganic tin (SnCl₂) and tetravalent inorganic tin (SnCl₄) caused DNA breakage in the presence of hydrogen peroxide (10 mM), and the DNA damage activity of inorganic tin was much more potent in divalent inorganic tin (SnCl₂) than in tetravalent inorganic tin (SnCl₄). Divalent inorganic tin (SnCl₂) induced DNA breakage in a concentration-dependent fashion at concentrations greater than 0.1 mM of SnCl₂ in the presence of hydrogen peroxide (10 mM). DNA breakage was not caused by n-butyltin compounds and methyltin compounds either in the presence or in the absence of hydrogen peroxide.     

Influence of humic substances on sorption and methylation processes of inorganic- and organo-tin species

The influence of humic substances on sorption and methylation processes for inorganic- and organotin species is presented. Four sediment samples from different locations of the Rivers Elbe, Mulde and Spittelwasser, Germany, with different organotin and humic contents were selected to extract the humic and fulvic acids. The various fractions—the original sediment, the humic acid, the fulvic acid and the residual sediment—were analysed for their organotin content. The individual buyltin species show quite different distribution patterns. Monobutyltin is found mostly associated with humic acids. Dibutyltin shows a nonunique behaviour. At low total organotin content, dibutyltin is found bonded to humic and fulvic acids, whereas at high organotin content dibutyltin is distributed more with the residual sediment. Most of the tributyltin remains in the sediment unextracted; only small quantities of it are in the fulvic acid fraction. Tetrabutyltin is only in the humic acid fraction when it binds to humic matter; it mostly remains in the sediment. General observations indicate that ionic butyltin species bind to fulvic acids whereas the non-polar tetrabutyltin is not found in the fulvic acid fractions in any of the samples. The appearance of monomethyl- and dimethyl-tin species in the humic and fulvic acid fractions after the alkaline extraction was surprising. There is a correlation between the humic content of the sample and the formation of methyltin species. Evidence is provided by experiments that humic substances act as methylation agents.     

Antimicorbial effects of newly synthesized organotin(IV) and organolead(IV) derivatives

Triorganotin(IV) and triorganolead(IV) derivatives of the types Me₃Sn(SCZ) and Ph₃Pb(SCZ) (where SCZ^? is the anion of a semicarbanzone ligand) have been synthesized by substitution reactions of trimethyltin chloride and triphenyl-lead chloride with semicarbazones derived from heterocyclic ketones. The resulting complexes have been characterized by elemental analyses, molecualr weight determinations and conductivity measurements. The mode of bonding has been established on the basis of infrared and ¹H, ¹³C and ¹¹⁹Sn NMR spectroscopic studies. Some respresentative complexes have also been evaluated for their antimicrobial effects on different species of pathogenic fungi and bacteria; the results of these investigations have been reported in the present paper.     

Synthesis,spectroscopic studies,and x-ray crystallographic analysis of the organotin carbohydrate: 1,2∶3,4-di-O-isopropylidene-6-O-triphenylstannylmethyl-α-D-galactopyranose

The title organotin carbohydrate, C₃₁H₃₆O₆Sn, has been synthesized and its molecular structure has been determined in solution and in the solid state. NMR, infrared, mass and X-ray crystallographic techniques were used. The chiral molecules crystallize in the monoclinic space group P2₁ withZ=2. The triphenyltin and carbohydrate moieties are linked by a trans methylene-oxygen-methylene arrangement. The pyranosyl ring adopts a twist-boat conformation and the isopropylidene rings adopt different (half-chair and envelope) forms. Solution and solid-state conformations are similar as only three ¹³C shift values are greater than 2ppm; the ¹¹⁹Sn value is 12 ppm.     

Adsorption of anions to zirconium(IV) and titanium(IV) chemically immobilized on gel-phase

Adsorption behaviors of 25 anions to zirconium(IV) and titanium(IV) chemically immobilized on a gel-phase were studied by ion chromatography and by batch adsorption experiments. The affinities of Zr(IV) to iminodiacetate as an anchoring group and to anions as a sample are much stronger than those of Ti(IV). On a Zr(IV) column, fourteen anions showed no retention, four anions showed pH-dependent retention in a low pH region, and seven anions were irreversibly adsorbed at pH <7. In the last group, fluoride was adsorbed both by the ligand exchange mechanism and the addition mechanism, while phosphate, arsenate and selenite were only by the ligand exchange mechanism. The structures of the adsorbed species are discussed.     

有机锡试剂在有机合成中的某些新应用

本文阐述有机锡试剂在有机台成巾的一些新应用。在钯催化下,有机锡试剂与亲电试剂进行偶联,条件温和,收率高。有机锡试剂促进醇醛缩合,可用于不对称合成中。