Search

A novel strategy was proposed and developed for eliminating spectral interference in the analysis of soft magnetic ferrite powders by inductively coupled plasma tandem mass spectrometry (ICP-MS/MS) in the MS/MS mode using mixed reaction gases. The samples were digested in a microwave-based digestion system using a mixture of nitric acid and hydrochloric acid. The contents of harmful elements (Na and Mg) and doping elements (Al, K, Ti and Co) in the digestion solution were determined by ICP-MS/MS. For spectral interferences in the complex matrix composition of different soft magnetic ferrite powders, in the MS/MS mode, the interferences were eliminated using mixed reaction gases of NH3/He/H2 through mass shift and on-mass methods. The limits of detection for Na, Mg, Al, K, Ti and Co were 16.6, 3.08, 5.40, 11.3, 0.64 and 0.53 ng L–1, respectively. The developed method was evaluated by sector field ICP-MS (SF-ICP-MS), and no significant difference was observed between the two analytical methods at a 95% confidence level, indicating that the developed method was accurate and reliable. This method was demonstrated as simple and quick and could be used for interference-free determination of Na, Mg, Al, K, Ti and Co in soft magnetic ferrite powders, providing a new technical means for the quality control of harmful and doping elements in soft magnetic ferrite powders.

A new organic-inorganic hybrid compound [H2biim]5.5[La0.35 ⊂ P6MoV4MoVI14O73]·10H2O (1) (biim = biimidazole) has been synthesized and characterized by IR, UV–Vis, XRD, XPS, elemental analysis, X-ray diffraction analysis and fluorescent spectrum analysis. Compound 1 exhibits a 3D supramolecular channel structure based on {La0.35Mo18P6O73} clusters through O┄O supramolecular interactions with biim molecules and water molecules locating in the channels through N H⋯O and O H⋯O hydrogen bonds. The photocatalytic activities of compound 1 for decompositions of rhodamine B (RhB) and methylene blue (MB) under the UV irradiation has also been investigated.

Three new compounds {[Ni(biim)(dipic)(H2O)][PSb2IIIMo6VMo6VIO40]·(Hbiim)}·1.5H2O (1); [(HTEA)(TEA)0.75]2 [PSb2IIIMo5V Mo7VIO40](2), (TEA)]2[HPSb2IIIMo4VMo8VIO40](3) (dipic = 2, 6- pyridine carboxylic acid, biim = 2, 2-biimidazole, TEA = triethylamine) have been synthesized under mild hydrothermal condition and structurally characterized by physico-chemical and spectroscopic methods. Single crystal X-ray diffraction analysis reveals that compound 1 represents new example formed by {PSb2Mo12O40} and transition metal mixed-organic-ligand complexes (TMMCs). The compounds 1–3 all exhibit novel 3D supermolecular channel structures through complex hydrogen bonds and strong O┄O supermolecular interactions. The photocatalytic activities of compounds 1–3 for decomposition of rhodamine B (RhB) and methylene blue (MB) under UV irradiation have also been investigated.

Three new supramolecular compounds [Cu0.5(H3O)2](H2prz)1.5[Mo5P2O23]·H2O (1); [4,4′-bpy]2[4,4′-H2bpy][H4Mo5P2O23]·4H2O (2); [4,4′-Hbpy][4,4′-bpy][H3Mo5P2O23]·2H3O (3); (pyz = pyrazine, bpy = 4,4′-bpyridine) have been hydrothermally synthesized and characterized by IR, UV-Vis spectroscopy, X-ray photoelectron spectroscopy (XPS), powder XRD analyses, TG analyses, cyclic voltammogram analyses, elemental analyses and single crystal X-ray diffraction analyses. Single crystal X-ray diffraction analysis reveals that there are multipoint hydrogen-bonding interactions in compounds 1–3. The structural features of the three compounds are that distinct one-dimensional (1D) chains are firstly formed, then the chains extend to form novel two-dimensional (2D) networks, finally unprecedented three-dimensional (3D) supramolecular host-guest structures were generated by Strandberg-type polyoxometaltes (POMs) and transition metal coordination complexes (TMCs) or organic ligands, and small organic guest molecules are exactly entrapped in void spaces via H-bonding interactions. The formations of the three distinct 3D supramolecular hybrid materials demonstrate the important role of H-bonds (non-covalent bond) in the construction of high dimensional architectures. Compounds 2–3 also show outstanding photocatalysis properties.

An analytical method for the determination of 26 impurity elements (such as Li, Be, Na, Mg, Al, Si, P, S, K, Ca, Sc, Ti, V, Cr, Co, Ni, Ga, Ge, Y, Nb, Mo, Ag, Cd, Sb, W and Pb) in MnZn ferrite powder by direct current glow discharge mass spectrometry (GD-MS) was established. MnZn ferrite powder was mixed with copper powder, used as a conductor, and pressed. The effects of MnZn ferrite powder preparation conditions and glow discharge parameters for the sensitivity and stability of signal analysis were investigated. By determining the choice of isotope and the application of the mass resolutions of 4000 (MR, medium resolution) and 10000 (HR, high resolution), mass spectral interference was eliminated. The contents of impurity elements in MnZn ferrite powder was calculated by subtraction after normalizing the total signal of Mn, Zn, Fe, O and Cu. The results showed that the detection limit of 26 kinds of impurity elements was between 0.002 and 0.57 μg/g, and the relative standard deviation (RSD) was between 3.33% and 32.35%. The accuracy of this method was verified by the ICP-MS. The method was simple and practical, which is applied to the determination of impurity elements in MnZn ferrite powder.

Two compounds [Cu(biim)]2(TEA)2[HPW12O40]·H2O (1); [Cu(im)2](im)[H2PMo12O40] (2), (biim = 2,2′-biimidazole, im = imidazole, TEA = triethylamine) have been hydrothermally synthesized and characterized by IR, XPS, XRD, UV-Vis, fluorescent spectra analysis, elemental analysis, X-ray diffraction analysis, cyclic voltammetric measurement and single crystal X-ray diffraction analysis. Single crystal X-ray diffraction analysis reveals that compounds 1–2 represent new examples formed by polyoxoanions, transition metal coordination complexes (TMCs) and organic amines. Compound 1 exhibits a 3-D supermolecular structure of which layers A and C are stacked alternatively, while compound 2 first shows a 1-D chain structure with an –A↑–A↓–A↑–A↓ linking mode, then along a, b and c axis, respectively exhibits different beautiful 2-D supramolecular networks via hydrogen bond interactions.The photodegradation properties of compounds 1–2 have been investigated.

Two new organic–inorganic hybrid compounds, [Cu(phen)(prz)]2[PMoV1MoVI7VIV2VV4O42]·4H2O (1) and [Ag2(phen)4]2[PMoV1MoVI7VIV2VV4O42] (2) (phen = 1,10-phenanthroline, prz = pyrazine), have been synthesized and characterized by IR, XPS, XRD, UV–vis, fluorescent spectra analyses, elemental analyses, X-ray diffraction analyses, TG analyses, and cyclic voltammetric measurements. Both compounds are formed by Keggin POM cores and transition metal fragments. Compound 1 exhibits an unprecedented 1-D chain structure constructed from [PMoV1MoVI7VIV2VV4O42]4− and [Cu(phen)(prz)]2+ in the –A–B↑–C–B↓– linking mode. Compound 2 shows a supramolecular structure formed by [PMoV1MoVI7VIV2VV4O42]4− and [Ag2(phen)4]2+.

Two new hybrid compounds, [Cu(1)(phen)(H2O)][Cu(2)(phen)(H2O)]([Cu(3)]0.25(H2O)][P2Mo5O23]·3.75H2O (1) and [Cu(en)2]1.5[P2Mo5O23]2·(enH2)3·2H2O (2) (phen = 1,10-phenanthroline, en = ethylenediamine), have been hydrothermally synthesized and characterized by IR, UV–Vis spectroscopy, X-ray photoelectron spectroscopy (XPS), powder XRD analyses, TG analyses, cyclic voltammogram analyses, elemental analyses, and single crystal X-ray diffraction analyses. Single crystal X-ray diffraction analyses reveal that the two compounds have a 1-D chain structure formed by Strandberg-type POMs and TMCs with –A–B–C–B–A–B–C–B– linking mode, then further extend into a 2-D layer structure through π⋯π or hydrogen bond interactions.

Using novel dual cathode/electro/Fe2+/S2O82-system to treat pickle sauerkraut wastewater, the paper investigates the influencing factors (S2O82-dosage, Fe2 +dosage, current density, Wastewater pH, electrode plate distance) of the organic matters removal and the treatment effect. Test results show that the degree of various factors influence on COD removal of sauerkraut wastewater is different. The COD removal is little effected by pH, while largely effected by current density, dosage of Fe2 +and S2O82-dosage. Under the optimum experiment conditions, current density for 30mA/cm-2, dosage of Fe2 +for 8mmol/L, S2O82-dosage for 12 mmol/L, electrode plate distance for 2 cm and pH=6, sixty minutes electrolysis, wastewater removal rate reach up to 92.6%. These results suggest that this electrochemical oxidation process by dual cathode/electro-Fe2+-S2O82-system might provide an alternative for the degradation of pickle sauerkraut wastewater.

In order to understand the transport mechanism and evaluate the biological safety of titanate nanotubes, the interactions of titanate nanotubes (TNTs) with bovine serum albumin (BSA) were investigated by applying spectroscopic methods under simulated physiological conditions. After taking into account the inner filter effect, the fluorescence intensity of BSA was found to be significantly enhanced by the presence of TNTs, indicating that the microenvironment of tryptophan and tyrosine residues in BSA became more hydrophobic. In addition, the absorption spectra of BSA showed a hyperchromic effect around 280 nm as the concentration of TNTs increased, suggesting that TNTs changed the microenvironment of the tryptophan and tyrosine residues. This is consistent with the results from fl uorescence spectroscopy studies. However, circular dichroism spectroscopy revealed that no signifi cant conformational change in BSA occurred during the interaction. We believe that Trp-213 was buried more compactly in the internal hydrophobic region, and hydrophobicity increased around Trp-134 with increasing TNTs concentration. From a spectroscopic point of view, this work elucidates the interaction mechanism of titanate nanotubes with BSA, and the methods used in this paper can also be applied to explore the molecular mechanism underlying toxicity of other nanomaterials.

A simple, rapid, and sensitive high-performance liquid chromatography (HPLC) method has been developed to simultaneously identify and determine five major active components from Dysosma difformis root, using a Diamonsil octadecyl bonded silica (ODS) C18 column (250 mm × 4.6 mm) and Photo-diode array (PDA) detector at 254 nm. Satisfactory separation was achieved by an isocratic elution with 0.1% aqueous phosphoric acid/methanol (40:60, v/v, pH = 3.2) at a flow rate of 1.0 mL/min. Four flavonoids (quercetin, kaempferol, rutin, and quercitrin) and a lignan (podophyllotoxin) in D. difformis root were well separated on the chromatogram within 24 min. Validation of the reverse phase HPLC (RP-HPLC) method showed good linearity (r2 > 0.9989) of the five compounds, which could be analyzed in relatively wide concentration ranges. The relative standard deviation values for intra-day and inter-day precision were less than 5.1%. The contents of these five active components in D. difformis root of different growth loca...

Two new compounds, namely [Cu 4 (4,4′-bpy) 4 ][SiW 12 O 40 ]·6H 2 O ( 1 ) and [Cu 2 (4,4′-bpy) 2 ][SiMo 12 O 40 ]·(H 2 4,4′-bpy) ( 2 ) (bpy = bipyridine), have been hydrothermally synthesized and characterized by IR, UV–Vis, X-ray photoelectron spectroscopy (XPS), powder XRD, elemental analyses and single crystal X-ray diffraction. The two compounds represent new examples of compounds constructed from Keggin polyanions, metal ions and organic ligands. Compounds 1 and 2 both contains Cu(4,4′-bpy) n n+ infinite chains and [SiM 12 O 40 ] 4− anions (M = W for 1 and M = Mo for 2 ). However, the structures of compounds 1 and 2 are thoroughly different. The Cu(4,4′-bpy) n n+ infinite chains and [SiW 12 O 40 ] 4− anions in compound 1 are connected into a 2-D layered framework structure, and the Cu(4,4′-bpy) n n+ infinite chains and [SiMo 12 O 40 ] 4− anions in compound 2 are linked into a 1-D ladder-like structure.

Two new compounds [Cu(enMe) 2 ][Cu(enMe) 2 (H 2 O)][SiMo V 6 Mo VI 6 Sb 2 O 40 ] ( 1 ) and [Ni(en) 2 ] 2 [SiMo V 6 Mo VI 6 Sb 2 O 40 ] ( 2 ) (enMe = 1,2-diaminopropane, en = 1,2-ethylenediamine) have been hydrothermally synthesized and characterized by IR, UV–Vis spectroscopy, X-ray photoelectron spectroscopy (XPS), powder XRD analyses, elemental analyses and single crystal X-ray diffraction. The two compounds represent the first examples of hybrids based on bi-antimony capped Keggin polyanions {SiMo 12 Sb 2 O 40 } and different transition metal coordination complexes.

Photodynamic therapy (PDT) is an effective, noninvasive and nontoxic therapeutics for cancer and some other diseases. It is becoming a alternative of traditional therapeutics for cancers. But the efficacy of PDT was restricted by insufficient selectivity and low solubility. In this study, novel multifunctional silica-based magnetic nanoparticles were prepared as targeting drug delivery system to achieve higher specificity and better solubility. Haematoporphyrin derivative (photosan) was used as photosensitizer. Magnetite nanoparticles (Fe3O4) and photosan were incorporated in silica nanoparticles by microemulsion and sol-gel methods. The prepared nanoparticles were characterized by X-ray diffraction, and transmission electron microscopy. The nanoparticles possessed good biocompatibility and could cause remarkable photodynamic anti-tumor effects. These suggested that photosan-Fe3O4 nanoparticles had great potential as effective drug delivery system in targeting photodynamic therapy.

Four new organic–inorganic hybrid compounds based on bicapped Keggin polyoxometalate {PMo12Sb2O40}: [H24,4′-bpy][PMo12Sb2O40]·6H2O (1), [Him]2[PMo12Sb2O40]·H2O (2), [H3(DABCO)2][PMo12Sb2O40]·2H2O (3) and [Mn(phen)3][PMo12Sb2O40] (4) (bpy = bipyridine, im = imidazole, DABCO = 1,4-diazabicyclo[2,2,2]octane, phen = phenanthroline) have been prepared hydrothermally and characterized by IR, UV–Vis spectroscopy, X-ray photoelectron spectroscopy (XPS), powder XRD analyses, elemental analyses, fluorescence analysis and single crystal X-ray diffraction analyses. The four compounds are new examples of hybrid compounds based on bicapped Keggin polyoxometalate {PMo12Sb2O40}. Compound 1, 2 and 3 are constructed from {PMo12Sb2O40} anions and different organic moieties, respectively. Compound 4 is formed by combining {PMo12Sb2O40} anions and manganese coordination complexes.

A new compound [Mo8V7O42][Cu(2,2′-bpy)2]2[Cu(2,2′-bpy)]·2H3O (1) has been synthesized under hydrothermal conditions and characterized by IR, UV–vis spectrum, elemental analysis, XRD, ESR, XPS, X-ray diffraction analysis and magnetic property study. Single-crystal X-ray structure analysis indicates that the compound 1 is a novel Keggin polyoxoanion tri-supported mixed-valent transition metal coordination complex.

An online rapid screening method, the high-performance liquid chromatography (HPLC)-diode array detector (DAD)-radical scavenging detection (RSD)-electrospray ionization (ESI)-mass spectroscopy (MS)/MS system, was developed for the screening and identification of radical scavengers from Neo-Taraxacum siphonanthum, a new species found in China in 1989. For further characterization, the target compounds were isolated by silica column chromatography, preparative high-performance liquid chromatography (HPLC), HSCCC, and Sephadex LH-20 column chromatography and elucidated on the basis of ultraviolet (UV), ESI-MS/MS, and nuclear magnetic resonance (NMR) spectroscopy, as well as the chemical analysis. Eighteen antioxidative polyphenols (5 caffeic acid derivatives and 13 flavonoid derivatives) were characterized from Neo-T. siphonanthum. The distribution of all compounds was discussed in a chemosystematic context, which suggested that the genera Neo-Taraxacum and Taraxacum might relate chemosystematically.

A polyoxometalate [Co(phen)3][Co(en)3][Co(en)2(H2O)2][Co(en)2]0.5[ O40(VIVO)2] · 6H2O (1) (en = ethylenediamine, phen = 1,10-phenanthroline) has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction, IR, electron paramagnetic resonance, X-ray photoelectron spectroscopy, elemental analyses, and thermogravimetry. The structure is an interesting 3-D supramolecular network containing bi-capped Keggin-type molybdenum–vanadium clusters with transition metal complexes generated in situ under mild hydrothermal conditions. Compound 1 contains four different counteractions being coordinated complexes of cobalt. The magnetic properties of 1 have also been studied in the temperature range of 4–300 K, and its magnetic susceptibility obeys the Curie–Weiss law, showing ferromagnetic coupling.

Two compounds based on polyoxometalates, (4,4′-H2bpy)7(4,4′-Hbpy)[ ]2[ ] ·10H2O (1) and (4,4′-H2bpy)6(4,4′-bpy)[ ]2 · 18H2O (2), have been prepared under hydrothermal conditions and characterized by IR, XPS spectra, TG analyses, and single crystal X-ray diffraction. Both compounds consist of 4,4′-bipyridine units and polyoxometalates: [ ]5− for 1 and [ ]6− for 2. In addition, 1 contains both Keggin-type and disordered Keggin-type anions, while 2 contains a (H2O)10 water cluster.

A novel modified POM [ H 4 PMo 7 V Mo 5 VI O 40 Sb 2 III ] (im)2·2H2O (im = imidazole) (1) has been hydrothermally synthesized from the system Sb2O3–H3PMo12O40–H2C2O4–im and characterized by elemental analysis, IR, UV–Vis, XPS, TGA and single crystal X-ray diffraction. The highly reduced polyoxoanion [ PMo 7 V Mo 5 VI O 40 Sb 2 III ] 4 - represents the first example of bi-antimony capped α-Keggin phosphomolybdate, in which the Sb atoms exhibit novel Ψ-rhombic pyramidal {SbO4E} hemidirected coordination geometry with coordination number 4.

Three novel heteropolyanions [PMo(12)Sb(2)O(40)][Cu(enMe)(2)].4H(2)O (), [PMo(12)Sb(2)O(40)][Ni(enMe)(2)].4H(2)O (2) and [PMo(12)Sb(2)O(40)][Cu(en)(2)].H(3)O.H(2)O (3) (enMe = 1,2-diaminopropane, en = ethylene diamine) have been synthesized and characterized by IR spectroscopy, X-ray photoelectron spectroscopy (XPS), thermogravimetric analyses and elemental analyses. Single-crystal X-ray diffraction analyses reveal that these three compounds represent the first examples of compounds based on the novel polyoxoanion {PMo(12)Sb(2)O(40)} and different transition metal coordination complexes. 1 and 2 are isostructural and both exhibit novel 1-D structures. In contrast to 1 and 2, 3 exhibits a substantially distinct novel 1-D structure. In addition, 3 is the first example of an extended structure constructed from polyoxoanions and Cu(+) transition metal coordination complexes.

Two new polyoxometalates [HN(C2H5)3]3[PMo12O40] (1) and [NH2(C2H4NH3)2]2[Mo5P2O23] (2) have been hydrothermally synthesized and characterized by IR, UV-Vis, XPS spectra, TG analyses, and single crystal X-ray diffraction. Crystal data for 1: monoclinic, space group C2/c, a = 24.651(5) A, b = 10.822(2) A, c = 22.413(5) A, β = 120.37(3)°, and V = 5158.7(18) A3; for 2: triclinic, space group P-1, a = 9.821(2) A, b = 9.948(2) A, c = 14.687(3) A, α = 95.490(3)°, β = 98.870(3)°, γ = 95.710(3)°, and V = 1401.7(5) A3. The crystal structure analyses reveal complex hydrogen bonds in both 1 and 2 in 3-D supramolecular arrays constructed from different polyoxoanions and organic ligands.

A novel compound PMo 10 VI V 4 IV O 42 Co(Phen) 2 ( H 2 O ) 2 PMo 10 VI V 4 IV O 42 Co(Phen) 2 2 · 2 OH - · 4 , 4 -bpy 1 which represents the missing link between the discrete POMs and the POMs as building blocks in extended structure has already been hydrothermally synthesized and characterized by elemental analysis, IR, UV–Vis, XPS spectrum, TG analysis and single-crystal X-ray diffraction analysis. The study of the magnetic susceptibility of the compound 1 demonstrates the presence of ferromagnetic interactions.

Two supramolecular compounds [Fe(2,2′-bipy)3]2[ (Cl)] · 4.67H2O (1) and [Ni(enMe)3]2[ (Cl)] · 2H2O (2) have been prepared under hydrothermal conditions and characterized by elemental analyses, IR, TGA, ESR, magnetic properties, and single crystal X-ray diffraction analyses. Crystal data for 1: tetragonal, I-42d, a = 13.6043(19), b = 13.6043(19), c = 50.544(10) A, V = 9354(3) A3; for 2: hexagonal, P6(3)/m, a = 12.6046(12), b = 12.6046(12), c = 22.563(5) A, V = 3104.4(7) A3. Compound 1 is constructed from cations [Fe(2,2′-bipy)3]3+, polyoxovanadates [ (Cl)]6−, and water molecules. Compound 2 is composed of cations [Ni(enMe)3]2+, clusters [ (Cl)]8−, and water molecules. There are hydrogen-bonding interactions between polyoxovanadates, organic moieties, and/or water molecules in 1 and 2, forming different 2-D layered networks.

It is challenging to screen and identify bioactive compounds from complex mixtures. We review a recently developed technique that couples high-performance liquid chromatography (HPLC) to on-line, post-column (bio)chemical assays and parallel chemical analysis to screen and identify bioactive compounds from complex mixtures without the need for cumbersome purification and subsequent screening. In this system, HPLC separates complex mixtures and a post-column (bio)chemical assay determines the activity of the individual compounds present in the mixtures. Parallel chemical-detection methods (e.g., diode-array detection, mass spectrometry and nuclear magnetic resonance) identify and quantify the active compounds simultaneously. We focus on relatively widely used on-line, post-column assays for antioxidant screening and less widely used hyphenated systems involving assays based on enzymes and receptors. These strategies have proved to be very useful for rapid profiling and identification of individual active components in mixtures to provide a powerful method for natural product-based drug discovery.

A novel polyoxometalate { P 2 V W 18 VI Ni 4 ( H 2 O ) 2 O 68 [ Ni ( en ) 2 ( H 2 O ) ] 2 } [ Ni ( en ) 3 ] 2 [ Ni ( en ) 2 ( H 2 O ) 2 ] · 14 H 2 O (1) has been hydrothermally synthesized and characterized by elemental analysis, IR spectrum, ESR spectrum and single crystal X-ray diffraction analysis. It is a novel Weakley-type POM supported transition metal coordination complex, also it contains a novel (H2O)14 water cluster in the structure. The study of the magnetic susceptibility of 1 demonstrates the presence of ferromagnetic interactions.

After an initial clean-up step on silica gel, a preparative high-speed counter-current chromatography coupled with on-line high-performance liquid chromatography-diode array detection method (HSCCC-HPLC-DAD) was successfully developed for the isolation and determination two polymethoxylated flavones, 3',4',7-trimethoxyquercetin and artemetin, from the aerial part of Taraxacum mongolicum. The HSCCC separation was performed with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (6:5:6:5, v/v/v/v) at a flow rate of 1.5 mL/min and at 800 rpm. The on-line purity monitoring of a representative aliquot from each HSCCC fraction was operated automatically. Using this method, fractions with high purity were collected. The HSCCC purification step was done in 5 h, and afforded 84.2 mg of 3',4',7-trimethoxyquercetin and 52.3 mg of artemetin, with purity over 98% from 200 mg of the enriched extracts of T. mongolicum. The structures were identified by electorspray ionization mass spectrometry and 1H NMR experiments. To our best knowledge, 3',4',7-trimethoxyquercetin was obtained from the plant of genus Taraxacum for the first time by our group. This hyphenated method could be used for the preparation of bioactive compounds with higher purity from natural products.

Two new polyoxometalates [ Ni ( phen ) 3 ] [ Ni ( en ) 3 ] [ Ni ( en ) 2 ( H 2 O ) 2 ] [ Ni ( en ) 2 ] 0.5 [ PW VI 7 W V 2 V IV 3 O 40 ( V IV O ) 2 ] · 6 H 2 O (1) and [ Ni ( phen ) 3 ] 2 [ Ni ( en ) 2 ] Na [ PW VI 7 W V 2 V IV 3 O 40 ( V IV O ) 2 ] · 8 H 2 O (2) (en=ethylenediamine, phen=1,10-phenanthroline) have been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction, IR, EPR, XPS, elemental analysis and thermogravimetry. Their structures exhibit interesting 3D supramolecular networks, and contain new bicapped (pseudo-) Keggin-type tungsten–vanadium cluster and the template transition-metal complexes (TMCs) being generated in situ under mild hydrothermal conditions. Interestingly, compound 1 contains four different kinds of nickel complex countercations.

Three new compounds, including one chloro-furoeremophilanoid (1), one eremophiladiolide (2), a rare dimer of nor-furoeremophilanoid, ligulatrovine A (3), and a known furoeremophilanolide (4), were isolated from Ligularia atroviolacea. The structures of compounds 1-4 were elucidated by spectroscopic methods including 1D and 2D NMR experiments as well as Xray diffraction study. (C) 2008 Shu Yun Shi. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

Following an initial cleanup step on the C18 open column chromatography, a preparative high speed countercurrent chromatography (HSCCC) method for isolation and purification of 8β‐H‐eremophil‐3,7(11)‐dien‐12,8α; 15,6α‐diolide, and furanoeremophil‐3‐en‐15,6α‐olide from the Chinese medicinal plant Ligularia atroviolacea was successfully established by a one‐step separation, using n‐hexane‐ethyl acetate‐ethanol‐water (4∶1∶4∶1, v/v/v/v) as the two phase solvent system. The upper phase was used as the mobile phase in the head to tail elution mode. HPLC analysis of the fractions collected on the preparative HSCCC of 600 mg of crude extracts showed that the purity of 8β‐H‐eremophil‐3,7(11)‐dien‐12,8α; 15,6α‐diolide (54.7 mg) was 98.1% and that of furanoeremophil‐3‐en‐15,6α‐olide (41.8 mg) was 98.4%. The chemical structures of the two eremophilane‐type sesquiterpenes were identified by ESI‐MS, 1H‐NMR, and 13C‐NMR analysis. To the best of our knowledge, 8β‐H‐eremophil‐3,7(11)‐dien‐12,8α; 15,6α‐diolide was...

Three new diarylheptanoids and one new monoterpenoid were isolated from the rhizomes of Zingiber officinale together with four known diarylheptanoids, 5-8. Their structures were elucidated mainly by spectroscopic methods, and they were deduced as 5-[4-hydroxy-6-(4-hydroxyphenethyl)tetrahydro-2 H-pyran-2-yl]-3-methoxybenzene-1,2-diol (1), sodium (E)-7-hydroxy-1,7-bis(4-hydroxyphenyl)hept-5-ene-3 S-sulfonate (2), sodium (E)-7-hydroxy-1,7-bis(4-hydroxyphenyl)hept-5-ene-3 R-sulfonate (3), and hydroxycineole-10-O-beta-D-glucopyranoside (4), respectively. Among the isolated compounds, compounds 1, 5, and 8 exhibited strong superoxide anion radical scavenging activities in a phenazine methosulfate-NADH system. In a more biological system, these compounds were demonstrated to exhibit potent protection against lipid peroxidation in mouse liver microsomes exposed to oxidative conditions. These compounds were subsequently tested on primary cultures of rat hepatocytes exposed to oxidative damage, and definitive cytoprotective actions were found.

Two new flavone glycosides, isoetin-7-O-beta-D-glucopyranosyl-2'-O-alpha-L-arabinopyranoside (1) and isoetin-7-O-beta-D-glucopyranosyl-2'-O-alpha-D-glucopyranoside (2), a new lignan, mongolicumin A (3), and a new guaianolide, mongolicumin B (4) were isolated from the aerial part of Taraxacum mongolicum. Their structures were elucidated mainly by spectral analyses. (c) 2007 Yu Zhao. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

Soil eco-toxicology provides a theoretical basis for ecological risk assessment of contaminated soils and soil pollution control. Research on eco-toxicological effects and molecular mechanisms of toxic substances in soil environment is the central content of the soil eco-toxicology. Eco-toxicological diagnosis not only gathers all the information of soil pollution, but also provides the overall toxic effects of soil. Therefore, research on the eco-toxicological diagnosis of soil pollution has important theoretical and practical significance. Based on the research of eco-toxicological diagnosis of soil pollution, this paper introduced some common toxicological methods and indicators, with the advantages and disadvantages of various methods discussed. However, conventional biomarkers can only indicate the class of stress, but fail to explain the molecular mechanism of damage or response happened. Biomarkers and molecular diagnostic techniques, which are used to evaluate toxicity of contaminated soil, can explore deeply detoxification mechanisms of organisms under exogenous stress. In this paper, these biomarkers and techniques were introduced systematically, and the future research trends were prospected.

Paclitaxel in southern yew tree was quantitatively determined by high performance liquid chromatography (HPLC) with ODS-C18 column. A mixture of CH3OH-H2O-CH3COOH(volume ratio: 55 : 44 : 1) is used as mobile phase and UV detection is carried out at 227 nm, and the column temperature is 20°C. The results show that there is a good linear relationship between the area of paclitaxel and the concentration of the sample in the range 50–500 mg/L for paclitaxel. The corresponding regression equation is Y=13021.7+1.01×106X, r=0.9990. The average recovery is 95.3% and the relative standard deviation is 2.08%.

The chemical constituents were isolated and purified by various chromatographic techniques indluding silica gel, reverse phase silica gel, sephadex LH-20 and pre-HPLC and identified by their physicochemical properties and spectral data. Sixteen phenolic compounds had been isolated and n-butanol extracts which were fractionated from the ethanol extract of Oplopanax horridus roots bark. Their structures were identified as below, including 7 phenylpropanoid compounds, ferulic acid (1), 3-acetylcaffeic acid (2), caffeic acid (3), homovanillyl alcohol 4-O-beta-D-glucopyranoside (4), 3-hydroxyphenethyl alcohol 4-O-beta-D-glucopyranoside (5), 3, 5-dimethoxycinnamyl alcohol 4-O-beta-D-glucopyranoside (6), and 3-dimethoxycinnamyl alcohol 4-O-beta-D-glucopyranoside (7). Three coumarins, scopoletin (8), esculetin (9) and 3'-angeloyl-4'-acetyl-cis-knellactone (10). And 6 lignan compounds, (+)-isolaricires-inol-9'-O-beta-D-glucopyranoside (11), 3, 3'-dimethoxy-4, 9, 9'-trihydroxy-4', 7-epoxy-5', 8-lignan-4, 9-bis-O-beta-D-glucopyranoside (12), (+)-5, 5'-dimethoxylariciresinol 4'-O-beta-D-glucopyranoside (13), (-)-5,5'-dimethoxylariciresinol 4'-O-beta-D-glucopyranoside (14), (-)-pinoresinol 4'-O-beta-D-glucopyranoside (15), and (+)-5, 5'-dimethoxylariciresinol 9'-O-beta-D-glucopyranoside (16). All compounds were isolated and identified for the first time from this plant All the constituents except compounds 4, 6, 12 and 13 were obtained for the first time from the genus Oplopanax.

A new compound [(BW 12 O 40 )Cd(2,2′-bpy) 2 (H 2 O)][Cd(2,2′-bpy) 3 ] 1.5 ·0.5H 2 O ( 1 ) has been hydrothermally synthesized and characterized by IR, UV–Vis, XPS spectrum, TG, XRD, elemental analysis and single crystal X-ray diffraction analysis. Crystal structure analysis reveals that 1 is the first Keggin polyoxoanion supported cadmium coordination complex.

A novel polyoxometalate [PW11O39Ni(4,4′-Hbpy)]·(4,4′-H2bpy)2·3H2O (1) has been hydrothermally synthesized and characterized by IR, XPS, TG, elemental analysis and single-crystal X-ray diffraction analysis. Crystal structure analysis reveals that 1 is a novel metal coordination fragment derivative of the classic Keggin polyanion.

A novel compound [P2W18M3O68][Cu(en)(2)](4)center dot 7H(2)O center dot 2OH(-) (M = 0.5W + 0.5Cu) 1 which contains the first example of extended structure constructed from Knoth-type sandwich polyoxoanions and transition metal coordination complexes has been hydrothermally synthesized and characterized by elemental analysis, IR spectrum, UV-Vis spectrum and single-crystal X-ray diffraction analysis. Crystal data for 1: triclinic, space group, P-1, a = 13.2718(7) angstrom, b = 13.6432(8) angstrom, c = 25.7307(15) angstrom, alpha = 104.7340(10)degrees, beta = 96.7630(10)degrees, gamma = 90.0330(10)degrees, V = 4472.2(4) angstrom(3), Z = 2. Structure solution and refinement based on 1090 parameters gave R1 (wR2) = 0.0409 (0.0993). (C) 2009 Elsevier B.V. All rights reserved.

A new cyclic diarylheptanoid, 1,5-epoxy-3-hyclroxy-1-(3-methoxy-4, 5-dihydroxyphenyl)-7-(4-hydroxyphenyl)-heptane (1), as well as a new monoterpene, 10-O-β-D-glucopyranosyl-hydroxy cineole (2) were isolated from the rhizomes of Zingiber officinale. The structures of compounds 1 and 2 were established based on their spectral data. In addition, the antioxidant activities of these compounds were also measured.

From Ligularia atroviolacea, four new eremophilendiolides, 8 beta-hydroxy-eremophil-3,7 (11)-dien-12,8 alpha(14,6 alpha)-diolide (1), 8 beta-methoxy-eremophil-3,7(11)-dien-12,8 alpha(14,6 alpha)-diolide (2), 8 alpha-hydroxy-eremophil-3,7(11)-dien-12,8 beta(14,6 alpha)-diolide (3) and eremophil-3,7(11),8-trien-12,8 (14,6 alpha)-diolide (4), as well as a known diolide (5) were isolated. Their structures were elucidated on the basis of 1D and 2D NMR as well as ESI-MS spectral data. (c) 2006 Yu Zhao. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

Two new polyoxometalates [ Ni ( phen ) 3 ] [ Ni ( en ) 3 ] [ Ni ( en ) 2 ( H 2 O ) 2 ] [ Ni ( en ) 2 ] 0.5 [ PW VI 7 W V 2 V IV 3 O 40 ( V IV O ) 2 ] · 6 H 2 O (1) and [ Ni ( phen ) 3 ] 2 [ Ni ( en ) 2 ] Na [ PW VI 7 W V 2 V IV 3 O 40 ( V IV O ) 2 ] · 8 H 2 O (2) (en=ethylenediamine, phen=1,10-phenanthroline) have been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction, IR, EPR, XPS, elemental analysis and thermogravimetry. Their structures exhibit interesting 3D supramolecular networks, and contain new bicapped (pseudo-) Keggin-type tungsten–vanadium cluster and the template transition-metal complexes (TMCs) being generated in situ under mild hydrothermal conditions. Interestingly, compound 1 contains four different kinds of nickel complex countercations.

To investigate the chemical constituents of the herbs of Taraxacum mongolicum.The chemical constituents were isolated by various column chromatographic methods and their structures elucidated mainly by NMR and MS evidences.Forty-four components were obtained and identified were as artemetin (1), quercetin (2), quercetin-3', 4', 7-trime-thyl ether (3), luteolin (4), luteolin-7-O-beta-D-glucopyranoside (5), luteolin-7-O-beta-D-galactopyranoside (6), genkwanin (7), isoetin (8), hesperetin (9), genkwanin-4'-O-beta-D-lutinoside (10), hesperidin (11), quercetin-7-O-[beta-D-glucopyranosyl (1--6) -beta-D-glucopyranoside (12), quercetin-3, 7-O-beta-D-diglucopyranoside (13), isoetin-7-O-beta-D-glucopyranosyl- 2'-O-alpha-L-arabinopyranoside (14), isoetin-7-O-beta-D-glucopyranosyl-2'-O-alpha-D-glucopyranoside (15), isoetin-7- O-beta-D-glucopyranosyl-2'-O-beta-D-xyloypyranoside (16), caffeic acid (17), furulic acid (18), 3-O-caffeoylquinic acid (19), 3, 5-di-O-caffeoylquinic acid (20), 3, 4-di-O-caffeoylquinic acid (21), 4, 5-di-O-caffeoylquinic acid (22), 1-hydroxymethyl-5-hydroxy-phenyl-2-O-beta-D-glucopyranoside (23), p-hydroxybenzoic acid (24), p-coumaric acid (25), 3, 5-dihydroxylbenzoic acid (26), gallic acid (27), gallicin (28), syringic acid (29), 3, 4-dihydroxybenzoic acid (30), caffeic acid ethyl ester (31), esculetin (32), rufescidride (33), mongolicumin A [6, 9, 10-trihydroxy-benzoxanthene-1, 2-dicarboxylic acid] (34), mongolicumin B [1 l-hydroxy-2-oxo-guaia-1 (10), 3, 5-trien-8, 12-lactone] (35), isodonsesquitin A (36), taraxacin (37), sesquiterpene ketolactone (38), taraxasteryl acetate (39), phi-taraxasteryl acetate (40) and lupenol acetate (41), palmitic acid (42), beta-sitosterol (43), and stigmasterol (44).Four compounds (14, 15, 34 and 35) were new compounds, compounds 1, 3, 6-13, 20-22, 30 and 31 were isolated from this genus for the first time, while compounds 18, 23-29, 32 and 37-42 were obtained from this species for the first time.

Two new compounds based on AsIII–VIV polyoxometalates, [HAs6V15O42(H2O)][Cu(enMe)2]2.5·2H2O (1), [H2enMe]2[As8V14O42(H2O)]·3H2O (2), have been hydrothermally synthesized and characterized by IR, UV-vis, ESR, XPS spectra, elemental analyses, magnetic susceptibility studies and single-crystal X-ray diffraction analyses, respectively. X-Ray crystallographic studies reveal that 1 represents the first example of 2D structure constructed from [HAs6V15O42(H2O)]5− anions and transition metal coordination complexes, in addition, it exhibits the first brick-wall-like 2D layer structure constructed from polyoxometalates and transition metal coordination complexes. 2 exhibits a very interesting stacking mode. The study of magnetic susceptibilities demonstrates the presence of antiferromagnetic interactions in both 1 and 2.

Two novel compounds have been hydrothermally synthesized and characterized by IR spectra and single crystal X-ray diffraction analyses. Crystal structure analyses reveal that 1 and 2 exhibit novel 2-D framework structures constructed from tungsten polyoxoanions, metal ions and 4,4-byp units, respectively.

Five novel heteropolyanions have been synthesized and characterized by IR, UV-vis, XPS spectroscopy, XRD, and elemental analyses. Single-crystal X-ray diffraction analyses reveal that these five compounds represent novel examples of compounds based on the combination of polyoxometalates, transition metal coordination complexes and organic amines. Of which 1, 2 and 3 exhibit 0D structures of polyoxometalate supported transition metal coordination complexes, while 4 and 5 exhibit novel 1D structures constructed from polyoxometalates and transition metal coordination complexes.

A novel POM compound containing the first Sb bicapped Keggin anion {SiMo(12)O(40)Sb(2)} and two different layers constructed from these anions stacked alternately has already been hydrothermally synthesized.