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941.
[Ru2(dNSAID)4Cl] and novel [Ru2(dNSAID)4(H2O)2]PF6 complexes, where dNSAID = deprotonated carboxylate from the non-steroidal anti-inflammatory drugs (NSAIDs), respectively: ibuprofen, Hibp (1) and aspirin, Hasp (2); naproxen, Hnpx (3) and indomethacin, Hind (4), have been prepared and characterized by optical spectroscopic methods. All of the compounds exhibit mixed valent Ru2(II, III) cores where metal–metal bonds are stabilized by four drug-carboxylate bridging ligands in paddlewheel type structures. The diruthenium complexes and their parent NSAIDs showed no significant effects for Hep2 human larynx or T24/83 human bladder tumor. In contrast, the coordination of Ru2(II, III) core led to synergistic effects that increased significantly the inhibition of C6 rat glioma proliferation in relation to the organic NSAIDs naproxen and ibuprofen. The possibility that the complexes Ru2-ibp and Ru2-npx may exert effects (anti-angiogenic and anti-matrix metalloprotease) that are similar to those exhibited by NAMI-A opens new horizons for in vivo C6 glioma model studies. 相似文献
942.
D. Canziani P.M. Ndiaye Elton Franceschi Marcos L. Corazza J. Vladimir Oliveira 《The Journal of chemical thermodynamics》2009,41(8):966-972
This work reports phase equilibrium experimental results for heavy petroleum fractions in pure propane and n-butane as primary solvents and using methanol as co-solvent. Three kinds of oils were investigated from Marlim petroleum: a relatively light fraction coming from the first distillation of crude petroleum at atmospheric pressure (GOP – heavy gas oil of petroleum), the residue of such distillation (RAT) and the crude petroleum sample. Phase equilibrium measurements were performed in a high-pressure, variable-volume view cell, following the static synthetic method, over the temperature range of 323 K to 393 K, pressures up to 10 MPa and overall compositions of heavy component varying from 1 wt% to 40 wt%. Transition pressures for low methanol and oil concentrations were very close for GOP, RAT, and crude Marlim when using propane as the primary solvent. Close to propane critical temperature, two and three-phase transitions were observed for GOP and Marlim when methanol was increased. When n-butane was used as primary solvent, all transitions observed were of (vapour + liquid) type with transition pressure values smaller than those obtained for propane. 相似文献
943.
Jana Sopkov‐de Oliveira Santos Marc‐Antoine Bazin Jean‐Franois Lohier La?la El Kihel Sylvain Rault 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(7):o311-o313
The stilbene derivative 1,2,3‐trimethoxy‐4‐[(E)‐2‐phenylvinyl]benzene, C17H18O3, (I), and its homocoupling co‐product (E,E)‐1,4‐bis(2,3,4‐trimethoxyphenyl)buta‐1,3‐diene, C22H26O6, (II), both have double bonds in trans conformations in their conjugated linkages. In the structure of stilbene (I), the aromatic rings deviate significantly from coplanarity, in contrast with coproduct (II), the core of which is rigorously planar. The deviation in stilbene (I) seems to be driven by intermolecular electrostatic interactions. Diene (II) sits on a crystallographic inversion centre, which bisects the conjugated linkage. 相似文献
944.
Carlos Kleber Z. Andrade Ricardo Alexandre F. Matos Viviane B. Oliveira Jussara A. Durães Maria J. A. Sales 《Journal of Thermal Analysis and Calorimetry》2010,99(2):539-543
Thermal properties of new ionic liquids (ILs) were investigated by thermogravimetry (TG/DTG) and differential scanning calorimetry (DSC). Chlorides, tetrafluoroborates and hexafluorophosphates of (−)mentholpyrrolidinium and (−)-mentholimidazolium cations revealed good thermal stability at air atmosphere. Morphological characteristics of poly(methyl methacrylate) (PMMA) matrices doped with 10% of these ILs were also investigated by DRX and water absorption test. Into the matrix, they exhibited a very satisfactory pattern concerning the polymer thermal stabilization. DSC results show that some of these ILs also present plasticizer features since they can lower the polymer glass transition temperature (T g) up to 317.15 K. 相似文献
945.
A method for determination of manganese and selenium in serum by simultaneous atomic absorption spectrometry (SIMAAS) is proposed. The samples (30 mul) were diluted (1+3) to 1.0% v/v HNO(3)+0.10% w/v Triton X-100 directly in the autosampler cups. A total of 20 mug Pd+10 mug Mg(NO(3))(2) was used as chemical modifier. The pyrolysis and atomization temperatures for the simultaneous heating program were 1200 and 2300 degrees C, respectively. The addition of an oxidant mixture (15% w/w H(2)O(2)+1.0% v/v HNO(3)) and the inclusion of a low temperature pyrolysis step (400 degrees C) attenuated the build-up of carbonaceous residues onto the integrated platform. An aliquot of 15 mul of the reference or sample solution was introduced into the graphite tube and heated at 80 degrees C; subsequently, 10 mul of oxidant mixture+10 mul of chemical modifier was introduced over that aliquot and the remaining heating program steps were executed. This strategy allowed at least 250 heating cycles for each THGA tube without analytical signal deterioration. The characteristic masses for manganese (6 pg) and selenium (46 pg) were estimated from the analytical curves. The detection limits were 6.5 pg (n=20, 3delta) for manganese and 50 pg (n=20, 3delta) for selenium. The reliability of the entire procedure was checked with the analysis of serum from Seronormtrade mark Trace Elements in Serum (Sero AS) and by addition and recovery tests (97+/-9% for manganese and 96+/-7% for selenium) using five serum samples. 相似文献
946.
Dalmora SL Júnior LB Schmidt CA Vaccari SF Oliveira PR Codevilla CF 《Journal of AOAC International》2004,87(6):1305-1308
Enoxaparin is a low-molecular weight heparin used clinically for the prevention and treatment of venous and arterial thrombosis. An anti-factor Xa assay was used to evaluate the potency of the final drug preparation. Method validation investigated parameters such as the range, linearity (r2 = 0.9971), precision, accuracy, and robustness; the biological assay incorporated a chromogenic endpoint and detection at 405 nm. The method yielded good results with a quantitation limit of 0.037 IU/mL and a detection limit of 0.011 IU/mL. The results demonstrated the validity of the anti-factor Xa assay for the determination of enoxaparin. 相似文献
947.
Trivinho-Strixino F Pereira EC Mello SV Oliveira ON 《Langmuir : the ACS journal of surfaces and colloids》2004,20(9):3740-3745
Nanostructured films from two conducting polymers, poly(o-methoxyaniline) (POMA) and poly(3-thiopheneacetic acid) (PTAA), were fabricated with the layer-by-layer (LBL) technique. The electrochemical response of the LBL films differs from that of a POMA cast film, even in a potential range where PTAA is inactive. This is attributed to differences in the diffusion-controlled charge and mass transport, where distinct ionic species participate in the LBL films, as demonstrated by quartz crystal microbalance measurements. The results show that the transport properties of conducting polymers can be changed by alternation with layers of appropriate materials in LBL films. 相似文献
948.
Manfredo Hrner Julieta Saldanha de Oliveira Jairo Bordinhao Johannes Beck 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(12):m586-m587
In the centrosymmetric title complex, [Ni(C7H7N4O3)2(C5H5N)2], the coordination geometry about the Ni2+ ion is octahedral, with two deprotonated 1‐methyl‐3‐(p‐nitrophenyl)triazenide 1‐oxide ions, viz. [O2NC6H4NNN(O)CH3]?, acting as bidentate ligands (four‐electron donors). Two neutral pyridine (py) molecules complete the coordination sphere in positions trans to each other. The triazenide 1‐oxide ligand is almost planar, the largest interplanar angle of 8.80 (12)° being between the phenyl ring of the p‐nitrophenyl group and the plane defined by the N3O moiety. The Ni—Ntriazenide, Ni—O and Ni—Npy distances are 2.0794 (16), 2.0427 (13) and 2.1652 (18) Å, respectively. 相似文献
949.
Fernando P. Carvalho João M. Oliveira 《Journal of Radioanalytical and Nuclear Chemistry》2009,281(3):591-596
The accuracy of alpha spectrometry in the determination of uranium isotopes at various concentrations levels and with various
isotope ratios was tested in a round robin international intercomparison exercise. Results of isotope activity/mass and isotope
mass ratios obtained by alpha spectrometry were accurate in a wide range of uranium masses and in isotopic ratios typical
of depleted, natural, and low enriched uranium samples. Determinations by alpha spectrometry compared very satisfactorily
in accuracy with those by mass spectrometry. For example, determination of U isotopes in natural uranium by alpha spectrometry
agreed with mass spectrometry determinations at within ±1%. However, the 236U isotope, particularly if present in activities much lower than 235U, might not be determined accurately due to overlap in the alpha particle energies of these two uranium isotopes. 相似文献
950.
Gelson Manzoni de Oliveira Gleison Antônio Casagrande Rozanna Marques Muzzi 《Journal of organometallic chemistry》2009,694(15):2463-2444
(PhSe)2 reacts with Br2, ethylenethiourea and PhTeBr3, further with I2, ethylenethiourea and PhTeI3, to give [PhSe(etu)][PhTeBr4] (1) (Ph = phenyl; etu = ethylenethiourea) and [PhSe(etu)][PhTeI4] (2) in very good yields.The tellurium centers present a distorted octahedral configuration, achieved through dimerization involving secondary, reciprocal Te···X interactions.In both compounds the anionic dimmers are linked through X···X interactions, attaining a one-dimensional, polymeric assembly along the b axis. Cations and anions are linked through short Se···X contacts. In addition to single crystal X-ray data, multinuclear NMR results for 1 and 2 are also presented and discussed. 相似文献