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101.
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Kazuo Furihata Haruo Seto Muneki Ohuchi Noboru Otake 《Magnetic resonance in chemistry : MRC》1983,21(10):624-627
A new method based on the combination of selective proton decoupling and INEPT is explained in detail. This technique, named selective INEPT (SEL-INEPT), is a useful and sensitive method for the 13C NMR assignment of methylene carbons with non-equivalent protons. The 13C NMR spectrum of monensin has been analysed by the application of this technique. 相似文献
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The plasminogen system is important in the proteolytic cascade that facilitates angiogenesis, a process that is essential for tumor growth and metastasis. The serine protease plasmin has a central role in the plasminogen system. This protease acts by degrading several components of the basement membrane and by activating other proteases. Therefore, inhibition of plasmin may be an effective method for blocking angiogenesis and, as a result, inhibiting the growth of primary tumors and secondary metastases. Three pairs of plasmin inhibitors were synthesized to compare the relative potency of inhibitors that are based upon a cyclohexanone or a tetrahydro-4H-thiopyran-4-one 1,1-dioxide nucleus. Compounds 1, 3, and 5 were cyclohexanone-based inhibitors, whereas compounds 2, 4, and 6 were tetrahydro-4H-thiopyran-4-one 1,1-dioxide-based inhibitors. Compounds 5 and 6 are reasonable inhibitors with IC50 values of 25 and 5.5 microM, respectively. Comparisons of the IC50 values of the three pairs show that the electron-withdrawing sulfone functional group is a beneficial element for the design of plasmin inhibitors. The presence of the sulfone increases inhibitor potency by a factor of 3-5 when compared to inhibitors that are based upon a simple cyclohexanone core. 相似文献
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Phenol derivatives, which are one of the most important classes of aromatic compounds in organic chemistry, were synthesized by ruthenium-catalyzed ring-closing olefin metathesis (RCM) of 1,4,7-trien-3-ones with versatile substitution patterns. The RCM reaction for producing phenol derivatives was also successful with 1,5,7-trien-3-one as another precursor. Most of the phenols prepared here could not be obtained easily by conventional methods. 相似文献
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We investigate a possible dynamical mechanism for spontaneous supersymmetrybreaking in N = 1 supergravity theories in 1 + 1 space-time dimensions. It will be shown that supersymmetry is never broken at the tree level, but it can be broken for a certain class of models by quantum effects due to trace anomalies of the energy-momentum tensor and the supercurrent. 相似文献
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We consider the explicit connection between linear representations of supersymmetry and the non-linear realizations associated with the generic effective lagrangians of the Volkov-Akulov type. We specify and illustrate a systematic approach for deriving the appropriate phenomenological lagrangian by transforming a pedagogical linear model, in which supersymmetry is broken at the tree level, into its corresponding non-linear lagrangian, in close analogy to the linear σ model of pion dynamics. We discuss the significance and some properties of such phenomenological lagrangians. 相似文献