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Nuclear magnetic resonance based structure of the protoberberine alkaloid coralyne and its self-association by spectroscopy techniques

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Journal of Pharmaceutical Analysis 2019年第6期9卷 437-448页

作者： Kumar Padmapriya Ritu Barthwal Department of Biotechnology Indian Institute of Technology Roorkee

Coralyne is an important alkaloid due to its anti-cancer and other medicinal *** targets DNA in cells and acts as human topoisomerase-I poison,telomerase inhibitor and nucleic acid *** has high tendency to undergo self-association,which is a matter of concern for therapeutic *** understanding of its interaction with DNA requires precise knowledge of chemical shifts in Nuclear Magnetic Resonance(nmr)spectra besides *** present study is the first report of a complete assignment of all 1H/13C resonances in nmr spectra of coralyne in DMSO-d6 using one dimensional 1H/13C and two dimensional nmr *** chemical shift of all proton and several 13C resonances have also been obtained in D2O and *** same has been calculated using Density Functional Theory(DFT).nmr spectra of coralyne show upfield shift of 0.6e1.2 ppm in aromatic ring protons suggesting stacking *** from 11 intra molecular NOE cross peaks in 2D 1H e1H ROESY spectra,3 short distance NOE correlations,H6e10OCH3,H5e10OCH3 and H12e16CH3,give direct independent evidence of the formation of a stacked *** absorbance,fluorescence,circular dichroism and fluorescence lifetime experiments conducted in the present investigations corroborate results obtained by nmr.

关键词： Coralyne alkaloid nmr spectra Chemical shift calculations Restrained molecular dynamics

Synthesis and characterization of novel heteronuclear complexes of Ln(Ⅲ)-Cu(Ⅱ) with non-cyclic polyether Schiff base

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Chinese Journal of Chemistry 1998年第5期16卷 430-435页

作者：姚克敏吴静徐青沈联芳袁汉珍 Department of Chemistry Zhejiang UniversityHangzhouZhejiang 310027 China Department of Chemistry Hangzhou Teacher's CollegeHangzhouZhejiang 310012 China Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of PhysicsChinese Academy of Sciences WuhanHubei 430071 China

Nine novel heteronuclear complexes of Ln(Ⅲ)-Cu(Ⅱ) with salicylidene tetraethvlcne glycol diamine (SALTTA) have been synthesized and *** have the general formulae [LnCu2(SALTTA)2(NO3)3](NO3)4 3H2O (Ln=La,***,Srn) and [LnCu3(SALTTA)3(NO3)5]-(NO3)4-4H2O (Ln=Gd,Tb,Er,Yb,Y).The IR spectra show that vc=N in the Ln(Ⅲ)-Cu(Ⅱ) het-eronuclear complexes are splitted up into two peaks with a far *** has been confirmed that oxygen atoms in oxyethylene of the ligand are not all coordinated to the central metal ions by both IR and nmr methods.

关键词： Lanthanide non-cyclic Schiff base heteronuclear complex nmr spectra

Synthesis and magnetic resonance of new heteropolynuclear Ln(III)-Cu(II) complexes with noncyclic polyether Schiff base

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Science China Chemistry 1998年第4期41卷 371-376页

作者：姚克敏吴静沈联芳袁汉珍 Department of Chemistry Zhejiang University Hangzhou China Department of Chemistry Hangzhou Teachers’ College Hangzhou China Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics & Mathematics Chinese Academy of Sciences Wuhan China

A series of novel heteropolynuclear complexes of Ln (II1)-Cu (I1) and Cu(11) complex with noncyclic polyether Schiff base, salicylidene diethylene glycol diarnine (SALDA), have been synthesized for the first time. The isolated complexes are formulated as [LnCu2(SALDAI3(NO3)5](N03)2.4H20 (Ln = La, Pr, Nd, Sm, Gd, Tb, Er, Yb, Y) and [Cu(SALDA)(NO3)](NO3). H20. Synthesis methods are reported herein. The differences in their compositions, structures and coordination have been investigated by UV, IR, magnetic susceptibility, especially by1H and13c nmr spectra. It has been found that v (C=N) in the Ln(II1)-Cu(II) complexes are split up into two peaks with a far distance and it may be used as a probe for distinguishing them from others. In addition, it is suggested that the ethereal oxygen donors are not all coordinated. The good catalysis effect for the polymerization of methyl methacrylate (MMA) are reported for the first time. The results show that the catalytic activity of Nd-Cu-SALDA complex is better than that of the others and its syndiotactic sequence is ～ 72 % as well, the conversion íncreases to 88%.

关键词： lanthanide noncyclic polyether Sehiff base heteropolynuclear complex nmr spectra

Synthesis and Structure of Tetrahydro-4,7- ethanoisobenzofuran-1,3-dione Derivative

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中国化学:英文版 2015年第5期33卷 573-577页

作者： Mingfeng Fang Chunmeng Pan Song Lu Zhongxiang Lin Guo-Yuan Lu College of Chemical Engineering Nanjing Forestry UniversityNanjingJiangsu 210037China Department of Chemistry Nanjing UniversityNanjingJiangsu 210093China

(1R,2R,3S,4R,7R)-7-Isopropyl-6-methylbicyclo[2.2.2]oct-5-ene-2,3-dicarboxylic acid anhydride(tetrahydro-4,7-ethanoisobenzofuran-1,3-dione derivative)adduct 2 was prepared via the isomerization ofα-pinene andβ-pinene in turpentine followed by the Diels-Alder cycloaddition with maleic anhydride in the presence of phosphoric acid/iodine *** molecular structure of adduct 2 was characterized by IR,1H nmr,13C nmr,1H-1H COSY,DEPT,HSQC,HMBC,2D NOESY and MS *** single crystal X-ray crystallographic analysis of adduct 2 was performed,and the X-ray powder diffractive spectrum of the sample adduct 2 is consistent with the diffractive spectrum calculated from the single crystal *** the structure and stereochemistry of adduct 2 was established based on extensive spectral data and single crystal X-ray analysis.

关键词： turpentine nmr spectra configuration crystal structure Diels-Alder reaction

Synthesis and Chemical Shifts Calculation of α-Acyloxycarboxamides Derived from Indane-1,2,3-trione by DFT and HF Methods

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Chinese Journal of Structural Chemistry 2012年第9期31卷 1346-1356页

作者： Hooriye Yahyaei Ali Reza Kazemizadeh Ali Ramazani Department of Chemistry Zanjan BranchIslamic Azad UniversityP.O.Box 49195-467ZanjanIran

α-Acyloxycarboxamides are synthesized from three-component Passerini reaction between indane-1,2,3-trione, isocyanides, and thiophenecarboxylic acids in quantitative yields. The structures of the final products were confirmed by IR, 1H and 13C nmr spectroscopy, mass spectrometry, and elemental analysis. The B3LYP/HF calculations for computation of 1H and 13C nmr chemical shifts have been carried out for the title compounds at the 6-311＋G＊＊ and 6-311＋＋G＊＊ basis set levels within GIAO and CSGT approaches. Predicted 1H and 13C nmr che-mical shifts have been assigned and compared with experimental 1H and 13C nmr spectra and they are supported each other.

关键词： DFT HF nmr spectra Passerini reaction isocyanide

Semi-Empirical and DFT Studies on Structures and spectra for C78（CH2）2

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Chinese Journal of Chemistry 2007年第2期25卷 149-153页

作者：吴师滕启文陈思聪 Department of Chemistry Zhejiang University Hangzhou Zhejiang 310027 China Department of Biomedicine-Engineering Zhejiang University Hangzhou Zhejiang 310027 China

Eighteen possible isomers of C78（CH2）2 weTe investigated by the INDO method. It was indicated that the most stable isomer was 42,43,62,63-C78（CH2）2, where the -CH2 groups were added to the 6/6 bonds located at the same hexagon passed by the longest axis of C78 （C2v）, to form cyclopropane structures. Based on the most stable four geometries of C78（CH2）2 optimized at B3LYP/3-21G level, the first absorptions in the electronic spectra calculated with the INDO/CIS method and the IR frequencies of the C-C bonds on the carbon cage computed using the AM1 method were blue-shifted compared with those of C78 （C2v） because of the bigger LUMO-HOMO energy gap and the less conjugated carbon cage after the addition. The chemical shifts of ^13C nmr for the carbon atoms on the added bonds calculated at B3LYP/3-21G level were moved upfield thanks to the conversion from sp^2-C to sp^3-C.

关键词： C78(CH2)2 electronic spectra IR spectra nmr spectra B3LYP/3-21G

The Synthesis and Regioselective Hydrolysis of Dialkyl 2-Phenylfuran (and 2-Phenyltetrahydrofuran) -3,4-dicarboxylates

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Chinese Chemical Letters 2002年第9期13卷 826-829页

作者： Shrong Shi LIN Bo YANG College of Chemical and Molecular Engineering Peking UniversityBeijing 100871

Dialkyl 2-phenylfuran (and 2-phenyltetrahydrofuran)-3,4-dicarboxylates (1, 2, 5-7), which are potential precursors of the synthesis of furofuran and tetrahydrofurofuran lignans, can be selectively hydrolyzed to monoacid (3, 8) by potassium hydroxide. The regioselective hydrolysis was affected significantly by the 2-phenyl group of the furan or tetrahydrofuran skeleton. The geometric structures of 3, 8 and related compounds were elucidated and verified by nmr spectra.

关键词： Regioselective hydrolysis nmr spectra dimethyl 2-phenylfuran-3,4-dicarboxylate.

Crystal and Molecular Structure of 4-Benzoyl-1,5-diphenyl-1H-pyrazole-3-carbonitrile

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Crystal Structure Theory and Applications 2012年第1期1卷 1-8页

作者： E.Korkusuz E.Sahin I.Yildirim Kayseri Vocational Colage Erciyes UniversityKayseriTurkey Department of Chemistry Faculty of SciencesAtaturk UniversityErzurumTurkey Department of Chemistry Faculty of SciencesErciyes UniversityKayseriTurkey

The crystal structure of potential active 4-benzoyl-1,5-diphenyl-1H*-pyrazole-3-carbonitrile (C23H15N3O) (I) has been determined from single crystal X-ray diffraction data. Also IR, Uv-vis and nmr spectral data were determined. The title compound crystallizes in the monoclinic space group P* 21/c, with a* = 9.3167(2), b* = 20.6677(3), c* = 10.6143(3) ?, β* = 112.665(3)°, V* = 1886.00(8) ?3, Dcalc* = 1.23g cm-3, Z* = 4. In the structure, intermolecular H*-bonds lead to the formation of a centrosymmetric dimmer of the molecule. Furthermore, the compound has a wide transmission window (300 to 1100 nm) with a transparency of nearly 100% and the UV cut-off wavelength occurs at 242 nm.

关键词： Pyrazole-3-Carbonitrile 2,3-Furandione Single Crystal Structure X-Ray Diffraction IR nmr spectra