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1.
Trimethylsulfonium hydroxide (TMSH) reproducibly converts fatty acids bound in, e.g., biomolecules such as phospholipids and/or glycerides, into the corresponding fatty acid methyl esters (FAMEs). The transesterification can be performed at room temperature in a fast single step reaction. Surprisingly, secondary alcohols and mycolic acid cleavage products (MACPs) are also released from mycobacteria under these conditions. The complex reaction mixtures containing FAMEs, MACPs, and secondary alcohols can easily be separated by high resolution temperature-programmed capillary GC. Different species of mycobacteria give rise to characteristic chromatographic patterns and the amount of lipids from a single colony of mycobacteria is sufficient for reliable identification of the bacteria. The profiles of the chromatograms match well those obtained from other sample preparation techniques. The TMSH method of identification of mycobacteria from the patterns of the gas chromatograms is faster and more sensitive than conventional methods, which also involve transesterification. The identification of mycobacterial species by microbiological culture techniques is difficult to perform and requires several weeks.  相似文献   

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The title salt, catena‐poly[trimethylsulfonium [μ2‐chlorido‐di‐μ2‐thiocyanato‐cadmate(II)]] {(C3H9S)[CdCl(NCS)2]}n, consists of trimethylsulfonium cations sandwiched between layers of a two‐dimensional polyanion. The CdII centre displays a distorted octahedral environment coordinated by two bridging Cl atoms, two thiocyanate N atoms and two thiocyanate S atoms. The thiocyanate groups adopt the μ‐1,3‐coordination mode and bridge the CdII centres into a one‐dimensional zigzag chain extended along the [110] direction. The CdII centres of the zigzag chains are crosslinked by bridging Cl atoms, forming a two‐dimensional polyanion. The two‐dimensional anions are linked to layers of trimethylsulfonium cations by weak intermolecular C—H...Cl hydrogen bonds, forming the three‐dimensional structure.  相似文献   

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In the title complex, [Hg(CH4N2S)4][Mn(NCS)4], the Hg and Mn atoms sit at special positions with symmetry and are tetrahedrally coordinated to four thio­urea (TU) S and four thio­cyanate (SCN) N atoms, respectively. The structure consists of discrete cationic and anionic [Hg(TU)4]2+ and [Mn(SCN)4]2− complexes, and weak NTU—H⃛SSCN hydrogen-bond bridges exist between these complexes.  相似文献   

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Summary Trimethylsulfonium hydroxide (TMSH) can convert fatty acids into the corresponding fatty acid methyl esters (FAMEs) in a single step. These fatty acids may also be bound in biomolecules such as phospholipids and/or glycerides. Complex mixtures of saturated and unsaturated FAMEs which may contain hydroxy and cylopropyl groups are obtained by trans-esterification; they can easily be separated in most cases by capillary GC. When FAMEs are generated from different microorganisms e.g. bacteria the patterns of the chromatograms are characteristic. Examples of characteristic patterns of bacteria with different cell wall structures are shown. The described method of transesterification can also be applied directly to blood serum without sophisticated sample pretreatment. The profiles of the chromatograms match well those described in the literature obtained by other methods of trans-esterification or sample preparation.  相似文献   

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Synthesis of amorphous and crystalline double hydrated cobalt copper and nickel copper ammine diphosphates with a coordination structure is described.__________Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 3, 2005, pp. 369–372.Original Russian Text Copyright © 2005 by Voitenko, Zhilyak, Kopilevich.  相似文献   

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The crystal structure of ethylenediaminecadmium(II) tetracyanocadmate(II)-benzene(1/2),I, has been redetermined based on 1632 reflections collected anew for the crystal coated with epoxy resin, with a final conventionalR=0.038;I crystallizes in space groupP4222, witha=b=8.265(1) andc=15.512(3) Å, andZ=2. Ethylenediaminecadmium(II) tetracyanocadmate(II),II, is concluded to be identical with the residual metal complex host ofI, remaining after the liberation of the guest benzene molecules;II crystallizes from an aqueous solution containing bis- or tris-ethylenediaminecadmium(II) tetracyanocadmate(II) in space groupI41/acd, witha=b=14.366(1) andc=23.771(4) Å, andZ=16; refinement led to a conventionalR=0.043 for 1181 reflections. The bridging ethylenediamine ligand inI turns to a chelating one inII; dissociation and recombination should occur in the coordination sphere of the six-coordinate cadmium atom, whenII is derived fromI by the liberation of the guest molecules. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82018 (30 pages).Dedicated to Professor H. M. Powell.  相似文献   

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Three new compounds, [Cd(μ 3 -Hpdh)(μ2-Cl)] n (1), Mn(Hpdh)2(H2O)2 (2) and Zn(Hpdh)2 (H2O)2 (3) (H2pdh =?pyridine-2,3-dicarbo-2,3-hydrazide), have been synthesized and characterized by elemental analysis, IR spectra, TG and single-crystal X-ray diffraction. Under hydrothermal conditions, H2pdh is generated by an in situ acylation of H2pda (H2pda =?pyridine-2,3-dicarboxylic acid) with hydrazine hydrate. Complex 1 features a 2D layer structure constructed by a dinuclear Cd(II) building block. In complexes 2 and 3, hydrogen bonding interactions connect mononuclear structures into 3D supramolecular frameworks.  相似文献   

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The title compounds, hexa­aqua­cobalt(II) bis­(hypophosphite), [Co(H2O)6](H2­PO2)2, and hexa­aqua­cobalt(II)/nickel(II) bis(hypophosphite), [Co0.5Ni0.5(H2O)6](H2PO2)2, are shown to adopt the same structure as hexa­aqua­magnesium(II) bis­(hypophosphite). The packing of the Co(Ni) and P atoms is the same as in the structure of CaF2. The CoII(NiII) atoms have a pseudo‐face‐centred cubic cell, with a = b~ 10.3 Å, and the P atoms occupy the tetrahedral cavities. The central metal cation has a slightly distorted octahedral coordination sphere. The geometry of the hypophosphite anion in the structure is very close to ideal, with point symmetry mm2. Each O atom of the hypophosphite anion is hydrogen bonded to three water mol­ecules from different cation complexes, and each H atom of the hypophosphite anion is surrounded by three water mol­ecules from further different cation complexes.  相似文献   

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Contact of thin layers of gelatin-immobilized copper(II) hexacyanoferrate(II) matrices with aqueous solutions of Co(II), Ni(II), Zn(II), and Cd(II) chlorides results in partial substitution of these ions for Cu(II) to give (dd)-heterobinuclear hexacyanoferrates(II) of copper(II) and the corresponding double-charged ion.  相似文献   

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Magnetic, spectroscopic and superoxide dismutase activity of imidazolate bridged [(Salala)Cu-Im-Cu(Salala)]Na, [(Salala)Cu-Im-Zn(Salala)]Na and [(Salala)Cu-Im-Ni(Salala)]Na (Salala=Salicyledenealiniate, Im=Imdiazolate) are described. The epr and electronic spectra of related mononuclear complexes, viz., [(Salala)Cu-OH(2)] and [(Salala)Cu-ImH] also described. Appearance of a half-field signal in polycrystalline and decrease in mu(eff) per copper(II) ion indicate super exchange coupling between copper(II) ion in [(Salala)Cu-Im-Cu(Salala)]Na binuclear complex. A pH-dependent epr and UV-vis study of 50% aqueous DMSO solution of binuclear complexes suggest that the complexes are stable in narrow pH range.  相似文献   

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Summary Complexes of the type M(AcLeu)2 · B2 (M = CoII, NiII or ZnII; B = H2O, py, 3-pic, 4-pic; AcLeu =N-acetyl-DL-leucinate ion) and M(AcLeu)2 B (M = CoII or ZnII and B = o-phen) were prepared and investigated by means of magnetic and spectroscopic measurements. The i.r. spectra of all the complexes are consistent with bidentate coordination of the amino acid to the metal ion. The room temperature solid state electronic spectra indicate that the symmetry of this species is closer toD 4h and that MO6 and MO4N2 chromophores are present in the M(AcLeu)2 · 2 H2O and M(AcLeu)2Bn · x H2O (B = py, 3-pic, 4-pic, n=2 and x=0 for M = NiII; B = o-phen, n=1 and x=0 for M = CoII; B = py, 3-pic, 4-pic, n=1 and x=1 for M = CoII) complexes, respectively. By comparing the Dq values of the amino acid and those of other N-substituted amino acids previously studied, a spectrochemical series of the the cobalt(II) and nickel(II) complexes is proposed. The1 H n.m.r. spectra of the zinc(II) complexes confirm the proposed stereochemistry.  相似文献   

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Metallatriazadiphosphorine complexes corresponding to [{N(PPh2NR)2}M(OAc)] and [{N(PPh2NR)2}2M], (R = Ph or SiMe3; M = Zn, Cd or Hg) have been synthesized under strictly anhydrous and inert conditions by the reaction of the acyclic bis-silylated phosphazene ligand, [HN(PPh2NSiMe3)2], or the bis-phenylated phosphazene ligand, [HN(PPh2NPh)2], with Zn, Cd and Hg acetate in 1:1 and 2:1 molar ratios. These complexes are highly soluble in common organic solvents, but unstable hydrolytically as well as thermally, even under reduced pressure. Molecular weight determinations in benzene indicated the monomeric nature of these complexes. Further, they have been characterized on the basis of elemental analysis and spectral studies: i.r. and n.m.r. (1H, 13C and 31P) that plausibly reveal a trigonal planar and tetrahedral geometry around the metal atom in the complexes.  相似文献   

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The synthesis of five homoleptic transition metal complexes of bis-(phenyl)-diisoindol-aza-methene is described together with the optical, electrochemical and thermal properties of these compounds. Additionally, crystal structures for the Co and the Zn complex are reported.  相似文献   

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