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Fluradoline (2-fluoro-11-[β-(methylamino)ethylthio]dibenz[b,f]oxepin), a novel analgesic with an unique profile, was found to be extensively metabolized in man as well as in other species. One of the major metabolites of this drug appeared to be a nuclear hydroxylated derivative of the parent compound, and the site of enzymatic hydroxylation was established to be C(7) by using high-field proton nuclear magnetic spectroscopy. This structural assignment was subsequently confirmed by the synthesis of an authentic sample of 2-fluoro-7-hydroxy-11-[β-(methylamino)ethylthio]dibenz[b,f]oxepin ( 2a ).  相似文献   
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The development of catalysts capable of fast, robust C?H bond amination under mild conditions is an unrealized goal despite substantial progress in the field of C?H activation in recent years. A Mn‐based metal–organic framework (CPF‐5) is described that promotes the direct amination of C?H bonds with exceptional activity. CPF‐5 is capable of functionalizing C?H bonds in an intermolecular fashion with unrivaled catalytic stability producing >105 turnovers.  相似文献   
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怀孕期头发中一些元素含量的变化趋势   总被引:5,自引:1,他引:4  
用同步辐射激发X射线荧光分析,对11个产妇怀孕期间头发内一些元素含量的变化趋势进行了测量,在各自对比的基础上,得到了一些结果。  相似文献   
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An elasto-plastic self-consistent (EPSC) polycrystal model is extended to account, in an approximate fashion, for the kinematics of large strains, rigid body rotations, texture evolution and grain shape evolution. In situ neutron diffraction measurements of the flow stress, internal strain, texture and diffraction peak intensity evolutions were performed on polycrystalline copper and stainless steel, up to true tensile strains of ε = 0.3. Suitably adjusted slip system hardening model parameters enable the model to quantitatively describe the flow stress of the polycrystalline aggregate. Quantitative predictions of the texture evolution and the internal strain evolution along the stress axis are good, while predictions of transverse internal strains (perpendicular to the tensile loading direction) are less satisfactory. The latter exhibit a large dispersion from grain to grain around a macroscopic average, and the implications of this finding for the interpretation of in situ neutron diffraction method are explored. Finally, as a demonstration of the applicability of the model to problems involving finite rotation, as well as deformation, simulations of simple shear were conducted which predict a texture evolution in agreement with published experimental data, and other modeling approaches as well.  相似文献   
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Luminescence from complexes of the general formula Ru(N-N-N)22+ (N-N-N = tridentate N-heterocyclic ligand) was investigated in the range of 77-2 K. Inversion of the sign of the polarization ratio occurred below 15 K. Results arr interpreted in terms of a thermally equilibrated multiple-state model for the excited manifold.  相似文献   
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