共查询到18条相似文献,搜索用时 170 毫秒
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用^1H,^13C NMR和多种二维磁共振谱表征了本系列化合物的结构,完成了^1H和^13C NMR谱带的归属,测定了氟原子对各质子和碳原子的偶合常数,探讨了影响偶合常数大小的因素。 相似文献
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研究了2-(三甲硅基)乙基硫代乙酸与(取代)苯胺和脂肪胺直接缩合反应或在五氧化二磷存在下的反应,发现前者收率高于后者。由此合成了17种结构新颖的2-(三甲硅基)乙基硫代(N-取代)乙酰胺类化合物。通过NMR(~1H,~(13)C)、IR和MS的研究,确定了这类化合物的结构,并探讨了化合物结构与波谱的关系。经测定,这些化合物的生物活性不甚理想。 相似文献
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用噁二唑硫酮杂环作为培氟沙星(1)的C3羧基电子等排体,得中间体C3噁二唑硫酮4(5),再将其与仲胺或取代苯胺及甲醛通过氨甲基化反应形成系列氟喹诺酮C3噁二唑硫酮曼尼希碱(6a ~6j)目标化合物.用元素分析、1H NMR和MS测试技术确证了目标化合物的组成和结构.采用MTT法评价了目标化合物对体外培养人肝癌Hep-3B细胞生长的抑制活性.结果表明,10种目标化合物活性均显著高于对照化合物1的活性,并且脂肪胺曼尼希碱的活性高于芳香胺曼尼希碱的活性. 相似文献
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13C nuclear magnetic resonance spectroscopy (NMR) was applied to determine the different components of apolar and polar fractions which were isolated by column chromatography from the crude chloroform-soluble waxes of olive fruits (Olea europaea) Dritta cultivar.13C NMR enabled the determination in the wax apolar fraction, of aliphatic aldehydes, and of benzyl, alkyl and glyceryl esters. In particular, the fatty acid composition of alkyl esters, comprising saturated and unsaturated oleic and linoleic acids, was determined. Acyl chain composition and the chain composition of 1,3- and 2-glycerol positions were also determined for triacylglycerols of olive fruit waxes.Oleanolic and maslinic acids were confirmed to be the major components of wax polar fraction. Complete assignments of 13C NMR chemical shifts of oleanolic and maslinic acids as a mixture were achieved by using homonuclear correlation spectroscopy with gradient (g-COSY), attached proton test (APT), inverse-detected heteronuclear single-quantum coherence with gradient (g-HSQC), high-resolution heteronuclear correlation spectroscopy (HETCOR) for C-H directly attached pairs and C-H long-range-coupled experiments. 相似文献
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This paper deals with the separation and characterization of alkyl phenol formaldehyde resins demulsifier by infrared spectrometry and nuclear magnetic resonance spectroscopy after separation of the different surfactants and low molecular additives by adsorption chromatography. Firstly, the types of surfactants are identified by methylene blue chloride-chloroform test method and the elemental analysis such as Ca, K, Mg, Na, P, S and N. Then, the different surfactants and low molecular components are separated by adsorption chromatography after parts of low molecular components are dried in an oven, and the molecular weight distribution is measured by gel permeation chromatography also. Finally, the separated surfactants are determined by Fourier transform infrared (FTIR) spectrometry and nuclear magnetic resonance (NMR) spectroscopy. The distortionless enhancement by polarization transfer (DEPT), H, C correlated spectroscopy (H, C-COSY), H, H correlated spectroscopy (H, H-COSY) and heteronuclear multiple-bond correlation (HMBC) spectroscopy are applied to determine the molecular structures. 相似文献
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报道了盐酸莫西沙星的元素分析、红外光谱(IR)、紫外光谱(UV)、质谱(MS)、氢-氢相关谱(1H-1HCOSY)、碳谱(DEPT-45、DEPT-90、DEPT-135)、多键碳氢相关谱(HMBC)等波谱数据,并对特征数据进行了化合物的结构解析.对所有的1H-NMR、13C-NMR谱的信号进行了归属. 相似文献
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The conformations of the major coat protein of a filamentous bacteriophage can be described by nuclear magnetic resonance spectroscopy of the protein and the virus. The NMR experiments involve detection of the 13C and 1H nuclei of the coat protein. Both the 13C and 1H nuclear magnetic resonance (NMR) spectra show that regions of the polypeptide chain have substantially more motion than a typical globular protein. The fd coat protein was purified by gel chromatography of the SDA solubilized virus. Natural abundance 13C NMR spectra at 38 MHz resolve all of the nonprotonated aromatic carbons from the three phenylalanines, two tyrosines, and one tryptophan of the coat protein. The alpha carbons of the coat protein show at least two different classes of relaxation behavior, indicative of substantial variation in the motion of the backbone carbons in contrast to the rigidity of the alpha carbons of globular proteins. The 1H spectrum at 360 MHz shows all of the aromatic carbons and many of the amide protons. Titration of a 1H spectra gives the pKas for the tyrosines. 相似文献