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排序方式: 共有459条查询结果,搜索用时 0 毫秒
451.
B. Raju M. Ramesh Roshan M. Borkar Raju Padiya Sanjay K. Banerjee R. Srinivas 《Journal of mass spectrometry : JMS》2012,47(7):919-931
In vivo metabolites of ketorolac (KTC) have been identified and characterized by using liquid chromatography positive ion electrospray ionization high resolution tandem mass spectrometry (LC/ESI‐HR‐MS/MS) in combination with online hydrogen/deuterium exchange (HDX) experiments. To identify in vivo metabolites, blood urine and feces samples were collected after oral administration of KTC to Sprague–Dawley rats. The samples were prepared using an optimized sample preparation approach involving protein precipitation and freeze liquid separation followed by solid‐phase extraction and then subjected to LC/HR‐MS/MS analysis. A total of 12 metabolites have been identified in urine samples including hydroxy and glucuronide metabolites, which are also observed in plasma samples. In feces, only O‐sulfate metabolite and unchanged KTC are observed. The structures of metabolites were elucidated using LC‐MS/MS and MSn experiments combined with accurate mass measurements. Online HDX experiments have been used to support the structural characterization of drug metabolites. The main phase I metabolites of KTC are hydroxylated and decarbonylated metabolites, which undergo subsequent phase II glucuronidation pathways. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
452.
Pai Rajesh V. Pillai K. T. Pathak Sachin Mukerjee S. K. Vinogradov V. V. Agafonov A. V. Vinogradov A. V. Aggarwal S. K. 《Journal of Sol-Gel Science and Technology》2012,61(1):192-196
Mesoporous γ-alumina samples were prepared by the sol–gel process from the boehmite sol having different template solutions.
Copper doped material was also prepared from sol containing template solution along with copper nitrate. Studies were performed
to understand the influence of templates on the morphology of the synthesized samples particularly with respect to specific
surface area and porosity. Synthesized samples were used to study sorption of Pu(IV) from nitric acid–oxalic acid solutions.
Distribution ratios (D) for Pu(IV) were determined using the γ-alumina samples with an objective to employ these for the recovery
of Pu. 相似文献
453.
Bosco EE Kumar S Marchioni F Biesiada J Kordos M Szczur K Meller J Seibel W Mizrahi A Pick E Filippi MD Zheng Y 《Chemistry & biology》2012,19(2):228-242
The NADPH oxidase enzyme complex, NOX2, is responsible for reactive oxygen species production in neutrophils and has been recognized as a key mediator of inflammation. Here, we have performed rational design and in?silico screen to identify a small molecule inhibitor, Phox-I1, targeting the interactive site of p67(phox) with Rac GTPase, which is a necessary step of the signaling leading to NOX2 activation. Phox-I1 binds to p67(phox) with a submicromolar affinity and abrogates Rac1 binding and is effective in inhibiting NOX2-mediated superoxide production dose-dependently in human and murine neutrophils without detectable toxicity. Medicinal chemistry characterizations have yielded promising analogs and initial information of the structure-activity relationship of Phox-I1. Our studies suggest the potential utility of Phox-I class inhibitors in NOX2 oxidase inhibition and present an application of rational targeting of a small GTPase-effector interface. 相似文献
454.
The Lie-group formalism is applied to investigate the symmetries of the Benjamin-Bona-Mahony (BBM) equation with variable coefficients. We derive the infinitesimals and the admissible forms of the coefficients that admit the classical symmetry group. The ordinary differential equations deduced from the optimal system of subalgebras are further studied and some exact solutions are obtained. 相似文献
455.
456.
457.
Sachin Handa Prof. LeGrande M. Slaughter 《Angewandte Chemie (International ed. in English)》2012,51(12):3028-3028
458.
A new series of Schiff base calamitic liquid crystal; methyl 4-(4′-n-alkoxybenzylideneamino)benzoate (MABAB), H2n+1C n OC6H4C(H)=NC6H4COOCH3 (n = 6, 8, 10, 12, 14, 16) has been synthesised and characterised by elemental analyses, Fourier transform infrared spectroscopy (FT-IR), 1H and 13C Nuclear Magnetic Resonance (NMR) spectroscopy. The mesomorphic properties of these compounds were studied by differential scanning calorimetry (DSC) and polarising optical microscopy (POM). All members of the series exhibit enantiotropic smectic A (SmA) mesophase. Temperature-dependent micro-Raman study of one of the members, MABAB-10 has been employed to identify phase transitions and the molecular rearrangement therein. Analysis of Raman marker bands; C–H in-plane bending, C–C stretching of phenyl rings and –C(H)=N– linking group of core confirms the transitions clearly as observed through DSC and POM. An in situ Raman measurement of C–H in-plane bending mode has also been performed to visualise the molecular changes more clearly. The Raman study gives an evidence of induced co-planarity of rings at Cr→SmA phase transition. The density functional theoretical (DFT) optimisation of monomer, dimer and rotational conformer of MABAB-10 also support the induced co-planarity at Cr→SmA phase transition. 相似文献
459.
Sachin S. PatilRahul P. Jadhav Sachin V. PatilVivek D. Bobade 《Tetrahedron letters》2011,52(43):5617-5619
A highly efficient and versatile iron catalyzed oxidative alkynylation of azoles with terminal alkynes under ligand and solvent-free conditions is described. 相似文献