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基于脉冲序列DEPT-(90+45)的二维核磁共振谱编辑技术
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作者 丁克洋 《分析测试学报》 CAS CSCD 2000年第6期48-50,共3页
基于作者提出的脉冲序列DEPT(distortionless enhancement by polarization transfer)-(90+45),拟定了一个二维破-氢相关实验,用于测定所有甲基的碳-氢相关信息... 基于作者提出的脉冲序列DEPT(distortionless enhancement by polarization transfer)-(90+45),拟定了一个二维破-氢相关实验,用于测定所有甲基的碳-氢相关信息。联合应用二维DEPT-135实验,从而实现了二维碳-氢相关谱的编辑,对于简化二维碳-氢相关谱具有实用价值。 展开更多
关键词 二维 编辑技术 DEPT -相关核磁共振
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叠氮二异丁基铝的构造及其缔合-解离平衡研究 被引量:2
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作者 张小航 高占先 《无机化学学报》 SCIE CAS CSCD 北大核心 2001年第6期819-824,共6页
叠氮二异丁基铝DBAA是一个新合成的化合物。通过相对分子质量的测定、氢核磁共振谱和铝核磁共振谱的测定确定了DBAA三聚体的分子构造在溶液中研究了DBAA的三聚体和单量体之间的缔合解离平衡。这个平衡受溶剂性质、温度的影响。借助铝核... 叠氮二异丁基铝DBAA是一个新合成的化合物。通过相对分子质量的测定、氢核磁共振谱和铝核磁共振谱的测定确定了DBAA三聚体的分子构造在溶液中研究了DBAA的三聚体和单量体之间的缔合解离平衡。这个平衡受溶剂性质、温度的影响。借助铝核磁共振谱和相对分子质量的测定计算了DBAA三聚体的解离平衡常数、解离焓和解离熵等热力学数据。 展开更多
关键词 叠氮二异丁基铝 相对分子质量 测定 氢-核磁共振谱 -核磁共振 缔合-解离平衡 叠氮有机铝化合物
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Substituent Effects on 13C NMR and 1H NMR Chemical Shifts of CH=N in Multi-substituted Benzylideneanilines
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作者 曹朝暾 王琳艳 曹晨忠 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2018年第1期45-51,I0001,共8页
Fifty-three samples of multi-substituted benzylideneanilines XArCH=NArYs (abbreviated XBAYs) were synthesized and their NMR spectra were determined. An extensional study of substituent effects on the 1H NMR chemical... Fifty-three samples of multi-substituted benzylideneanilines XArCH=NArYs (abbreviated XBAYs) were synthesized and their NMR spectra were determined. An extensional study of substituent effects on the 1H NMR chemical shifts (δH(CH=N)) and 13C NMR chemical shifts (δc(CH=N)) of the CH=N bridging group from di-substituted to multi-substituted XBAYs was made based on a total of 182 samples of XBAYs, together with the NMR data of other 129 samples of di-substituted XBAYs quoted from literatures. The results show thatthe substituent specific cross-interaction effect parameter (△(∑σ)2) plays an important role in quantifying the δc(CH=N) values of XBAYs, but it is negligible for quantifying the δH (CH=N) values; the other substituent parameters also present different influences on the δc (CH=N) and (δH (CH=N). On the whole, the contributions of X and Y to the δc (CH=N) of XBAYs are balanced, but the δH(CH=N) values of XBAYs mainly rely on the contributions of X. 展开更多
关键词 Multi-substituted benzylideneanilines Substituent effects 1H NMR chemicalshifts 13C NMR chemical shifts Substituent specific cross-interaction effect
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丙烯酸-2,4,6-三硝基苯乙酯的合成及热分解 被引量:2
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作者 刘强强 金波 +3 位作者 彭汝芳 舒远杰 楚士晋 董海山 《含能材料》 EI CAS CSCD 北大核心 2012年第5期579-582,共4页
以TNT、甲醛为原料,在弱碱性条件下反应合成得到2,4,6-三硝基苯乙醇(PicCH2CH2OH);PicCH2CH2OH在浓硫酸催化下和丙烯酸在甲苯中回流反应24h,合成得到丙烯酸-2,4,6-三硝基苯乙酯,产率为62%。采用紫外可见光谱(UV-Vis)、核磁共振氢谱(1HN... 以TNT、甲醛为原料,在弱碱性条件下反应合成得到2,4,6-三硝基苯乙醇(PicCH2CH2OH);PicCH2CH2OH在浓硫酸催化下和丙烯酸在甲苯中回流反应24h,合成得到丙烯酸-2,4,6-三硝基苯乙酯,产率为62%。采用紫外可见光谱(UV-Vis)、核磁共振氢谱(1HNMR)、红外光谱(FTIR)、质谱(MS)以及元素分析等对产物结构进行了表征。利用热重分析(TG)对产物热稳定性进行了研究,采用Kissinger方法和Ozawa方法计算其热分解活化能Ea分别为99.78,102.96kJ·mol-1。 展开更多
关键词 有机化学 2 4 6-三硝基苯乙醇 丙烯酸-2 4 6-三硝基苯乙酯 热稳定性 活化能
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Synthesis and antiviral bioactivities of novel chiral bis-thiourea-type derivatives containing α-aminophosphonate moiety 被引量:5
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作者 YANG Xuan SONG BaoAn +5 位作者 JIN LinHong WEI Xue BHADURY S Pinaki LI XiangYang YANG Song HU DeYu 《Science China Chemistry》 SCIE EI CAS 2011年第1期103-109,共7页
Starting from 1-((1R,2R)-2-aminocyclohexyl)-3-substituted thioureas (3a–c) and substituted isothiocyanates (9a–d),chiral bis-thiourea derivatives containing α-aminophosphonate moiety 10a–l were prepared and comple... Starting from 1-((1R,2R)-2-aminocyclohexyl)-3-substituted thioureas (3a–c) and substituted isothiocyanates (9a–d),chiral bis-thiourea derivatives containing α-aminophosphonate moiety 10a–l were prepared and completely characterized by elemental analysis,physical and spectral (IR,1H NMR,13C NMR,31P NMR) data.The results of bioassay revealed that compounds 10a and 10e possessed appreciable curative bioactivities on cucumber mosaic virus (CMV) at 0.5 mg/mL in vivo (inhibitory rate = 60.3%,64.8% respectively) and tobacco mosaic virus (TMV) at 0.5 mg/mL in vivo (inhibitory rate = 50.3%,50.8% respectively),which were comparable to the values shown by standard reference (58.7%) and commercial product Ningnanmycin (56.3%),respectively.Chiral compound 10e displayed more potent antiviral activity (EC50 = 0.149 mg/mL) than Ningnanmycin (EC50 = 0.201mg/mL) against CMV. 展开更多
关键词 chiral bis-thiourea α-aminophosphonate moiety antiviral activity SYNTHESIS
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Application of a quantitative ^1H NMR method for rapid extraction and determination of the content of paeonol in Cynanchum paniculatum 被引量:3
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作者 Xuejiao Li Jianwei Dong +3 位作者 Xiu Gao Guijun Li Junyou Shi Yanqing Zhang 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2020年第6期422-430,共9页
Cynanchum paniculatum(Bunge) Kitagawa is usually used as an herbal medicine for treating many diseases. Paeonol is the main active component, and its content is the key indicator for quality control of C. paniculatum.... Cynanchum paniculatum(Bunge) Kitagawa is usually used as an herbal medicine for treating many diseases. Paeonol is the main active component, and its content is the key indicator for quality control of C. paniculatum. In the present study, we developed a rapid, accurate and precise method for quantitation of paeonol in C. paniculatum using 1 H NMR spectra. The deuterated solvent of methanol-d4 enabled satisfactory separation of the signals to be integrated in 1 H NMR spectrum. H-6(δ 7.78) of 1 H NMR spectrum of C. paniculatum was selected as the feature signal for quantitation, and trimesic acid(TMA) was selected as an internal standard. Validation of the quantitative method was performed in terms of linearity, specificity, repeatability and stability. This is the first time to report quantitative 1 H NMR(qHNMR) applied to determine the content of paeonol in C. paniculatum and showed a wider linearity range than the reported quantitation of paeonol in others. The simple extraction of paeonol from C. paniculatum was rapid and will prompt the application of the developed method. This work implied that qHNMR represented a feasible alternative to HPLC-based methods for quantitation of paeonol in C. paniculatum, and it was suitable for the quality control of C. paniculatum. 展开更多
关键词 Cynanchum paniculatum Quantitative ^1H NMR PAEONOL Quantitative determination
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