共查询到16条相似文献,搜索用时 265 毫秒
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Parisaponin I 和Parisvietnaside A 的NMR数据分析 总被引:1,自引:0,他引:1
从滇重楼中分离得到2个甾体皂苷,利用1H NMR、13C NMR、1H-1H COSY、HSQC、 HMBC、1D和2D TOCSY等多种核磁共振方法鉴定其结构分别为(25R)-26-O-β-D-吡喃葡萄糖基-3β, 22α, 26-三羟基-呋甾-5-烯- 3-O-α-L -吡喃鼠李糖基-(1→2)[α-L-呋喃阿拉伯糖基(1→4)]-β-D-吡喃葡萄糖苷(1, Parisaponin I)和(25R)-3β, 5α, 6β-三羟基-△7-螺甾烯-3-O-β-D-吡喃葡萄糖基-(1→3)[α-L-吡喃鼠李糖基-(1→2)]-β-D-吡喃葡萄糖苷(2, parisvietnaside A). 对化合物1和2的1H NMR和13C NMR信号分别进行了归属和详细分析,并纠正了文献中的核磁数据归属错误. 化合物2为首次从滇重楼中分离得到. 相似文献
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对3′″-羰基-2″-β-L-奎诺糖基淫羊藿次苷Ⅱ(3′″-carbonyl-2″-β-L-quinovosyl icariside Ⅱ),进行了1H和13C MNR检测,参考2″-O-鼠李糖基淫羊藿次苷Ⅱ (2″-O-rhamnosyl icarisid Ⅱ)、淫羊藿次苷Ⅱ(icarisid Ⅱ)和淫羊藿苷(icariin)的1H、13C NMR数据,通过DEPT和1H-1H COSY、HSQC、HMBC等2D NMR技术对该化合物所有的1H和13C NMR信号进行了全归属和详细解析. 相似文献
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Govinda Lakhotiya Namdeo Belsare Abhimanyu Rana Vinay Gupta 《Current Applied Physics》2019,19(4):394-399
Here, we report Cu2S nanocrystals based non-fullerene ternary polymer solar cells by incorporating Cu2S in conjugated polymer (PBDB-T: poly[(2,6-(4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)-benzo[1,2-b:4,5-b′]dithiophene))-alt-(5,5-(1′,3′-di-2-thienyl-5′,7′-bis(2-ethylhexyl) benzo[1′,2′-c:4′,5′-c′]dithiophene-4,8-dione))]) and small molecule non-fullerene compound (ITIC:3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)-indanone))-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3-d:2′,3′-d′]-s-indaceno[1,2-b:5,6-b′]dithiophene). The devices were fabricated in inverted configuration i.e. ITO/ZnO/PBDB-T: Cu2S NCs: ITIC/MoO3/Ag. Effect of concentration of Cu2S nanocrystals on the performance parameters of PBDB-T: ITIC based organic solar cells is studied. An enhancement in the power conversion efficiency from 8.24% to 9.53% is achieved for the optimum concentration of Cu2S nanocrystals in the organic photoactive blend. The cause of improvement in the performance parameters of the device is investigated by means of the light intensity dependent electrochemical impedance spectroscopy and atomic force microscopy. It is found that the devices with Cu2S nanocrystals have less trap-assisted recombination. 相似文献
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应用2D NMR技术研究羌活苷的结构 总被引:7,自引:0,他引:7
从传统中药羌活中分离得到1个香豆素类化合物,应用1D和脉冲梯度场反相2D NMR检测技术 (gCOSY, gNOESY, gHMQC, gHMBC) 研究了其结构,鉴定为6′-O-(反式阿魏酰基)-紫花前胡苷,命名为羌活苷(Forbesoside). 本文对其碳氢NMR信号进行了全归属. 对从伞形花内酯衍生化为7-去甲基软木花椒素、紫花前胡苷元和6′-O-(反式阿魏酰基)-紫花前胡苷的NMR信号变化规律以及糖残基NMR信号归属方法进行了讨论和总结. 相似文献
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维库溴胺合成中的6个中间体均为雄甾类化合物,我们以重要中间体2β,16β-二(1-哌啶基)-5α-雄甾烷-3α, 17β-二醇为例,使用质谱、红外光谱和核磁共振技术确定了它的结构,并结合1H NMR, 13C NMR, DEPT, 1H-1H COSY, HSQC, HMBC多种核磁共振分析方法,详细归属了其所有的1H NMR和13C NMR数据,利用ROESY确定了其相对构型. 根据相同方法,归属了其它5个中间体的13C NMR数据,为它们的结构鉴定提供了重要依据,为维库溴铵合成工艺的中间体质量控制提供了参考数据. 相似文献
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Naokazu Yoshikawa Shinichi Yamabe Nobuko Kanehisa Tsuyoshi Inoue Hiroshi Takashima Keiichi Tsukahara 《Journal of Physical Organic Chemistry》2010,23(5):431-439
A series of new metal‐free blue emission compounds, i.e., diprotonated terpyH2ClPF6 ( 1 ), tterpyH2ClPF6 ( 2 ), ClterpyH2ClPF6 ( 3 ), and BterpyH2(PF6)2 ( 4 ), were prepared and characterized by electrospray ionization mass spectrometry, UV–vis spectroscopy, and cyclic voltammetry (CV). Abbreviations used are terpy = 2,2′:6′,2″‐terpyridine, tterpy = 4′‐(4‐tolyl)‐2,2′:6′,2″‐terpyridine, Clterpy = 4′‐chloro‐2,2′:6′,2″‐terpyridine, and Bterpy = 4,4′,4″‐tert‐butyl‐2,2′:6′,2″‐terpyridine. The X‐ray crystal structures of the three new compounds 1, 2, and 4 were determined. Both protonated pyridine rings of the terpyridine derivatives are hydrogen bonded intermolecularly to the adjacent Cl? ion in compounds 1 , 2, and 3 . The π–π* absorption bands in the UV region for 1, 2, 3, and 4 in acetonitrile were red‐shifted relative to those of the corresponding neutral compounds. All the compounds exhibited stronger emissions (around 400 nm) than their neutral counterparts. All the CVs for the diprotonated species, terpyH, tterpyH, ClterpyH, and BterpyH, showed the first reduction waves around ?0.6 V, which were more positive than those of the neutral ones. Density functional theory was applied to interpret the remarkable differences in the interaction of the Cl? ion. The attachment of two protons to the two terminal Bterpy nitrogens in 4 elicits remarkable characteristics. Both positive charges on the nitrogens are delocalized over the conjugated pyridine systems and the tertiary carbonium ions are stabilized to lead to stronger emission (Φ = 0.35) than the corresponding neutral Bterpy (Φ = 0.045). CCDC 732045–732047 contains the supplementary crystallographic data for this paper. These data can be obtained free of charge from the Cambridge Crystallographic Data Centre via www.ccdc.cam.ac.uk/data_request/cif Copyright © 2010 John Wiley & Sons, Ltd. 相似文献