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Diastereoselective Syntheses of (+)-α-Cyperone and Its C-10 Epimer

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Chemical Research in Chinese Universities 1998年第3期14卷 126-128页

作者： ZOU Ning chenG Dong liang PAN Xin fu chen yao zu Department of Chemistry State Key Laboratory of Applied Organic ChemistryLanzhou UniversityLanzhou730000

Ｉｎｔｒｏｄｕｃｔｉｏｎ（＋）－α－Ｃｙｐｅｒｏｎｅ（１）ａｎｄ（－）－α－１０－ｅｐｉｃｙｐｅｒｏｎｅ（２）ａｒｅｗｉｄｅｌｙｕｓｅｄａｓｃｈｉｒａｌｔｅｍｐｌａｔｅｓｆｏｒｔｈｅｓｙｎｔｈｅｓｉｓｏｆｏｔｈｅｒｓ... 详细信息

Ｉｎｔｒｏｄｕｃｔｉｏｎ（＋）－α－Ｃｙｐｅｒｏｎｅ（１）ａｎｄ（－）－α－１０－ｅｐｉｃｙｐｅｒｏｎｅ（２）ａｒｅｗｉｄｅｌｙｕｓｅｄａｓｃｈｉｒａｌｔｅｍｐｌａｔｅｓｆｏｒｔｈｅｓｙｎｔｈｅｓｉｓｏｆｏｔｈｅｒｓｅｓｑｕｉｔｅｒｐｅｎｅｄｅｒｉｖ...

关键词： (+)-T-Cyperone (-) -T-10-Epicyperone Diastereoselective synthesis

Relationship Between the Shape of Suspension Particle and Ground State Structure of Electrorheological Solid

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Chinese Physics Letters 2000年第5期17卷 379-381页

作者： WU Feng HE Pei chen zu-yao JIANG Wan-Quan Department of Mechanics and Mechanical Engineering University of Science and Technology of ChinaHefei 230026 Department of Chemistry University of Science and Technology of ChinaHefei 230026

The effect of the shape of suspension particle in electrorheological(ER)fluid on the ground state structure of ER solid is *** results of computation show that the ground state structure will change with the shape of suspension *** phenomenon is a kind of phase transitions that takes the shape factors of suspension particle as tuning *** variation-value of interaction energy of the lattice structure of ER solid with the shape factors of suspension particle is sometimes noticeable.

关键词： parameters. particle structure

Amino acid identification and sequence analysis of peptides by reaction mass spectrometry

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Chinese Journal of Chemistry 1993年第6期11卷 540-549页

作者： YANG Hou-Jun HU Xiao-Yu chen yao-zu State Key Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhou 730000 National Laboratory of Biomacromolecules Institute of BiophysicsChinese Academy of SciencesBeijin9100101

Fast atom bombardment mass spectrometry (FAB-MS) is applied to distinguish N- terminal series ions from C-terminal series ions of a peptide by on-probe acetylation, it provides valuable information about the sequence of an unknown peptide. The FAB mass spectra contain a number of characteristic ions at low-mass region in addition to the sequence ions at high-mass region. It was found that the ions below m/z 200 are characteristic of the amino acid composition of the peptide, from which the amino acid composition of the peptide could be estimated. Additionally, mixture analysis is also discussed.

关键词： Pro Amino acid identification and sequence analysis of peptides by reaction mass spectrometry acid

Stereochemical effects in mass spectra—Studies on mass spectra of epimers of podophyllotoxin and its derivatives

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Chinese Journal of Chemistry 1986年第1期4卷 35-41页

作者： chen yao-zu HUA Su-Ming chen Nen-Yu Department of Chemistry, Lanzhou University, Lanzhou Department of Chemistry Lanzhou University Lanzhou

Mass spectra of thirteen epimers of podophyllotoxin and its derivatives have been exa-mined. By means of high resolution mass spectrometry, metastable ion scanning and isotope-labeling techniques, the effects of configuration of C3-OH and condensed lactone ring on the frag-mentation pattern and the relative abundanees of characteristic ions in the mass spectra of these com-pounds have been studied and rationalized.

关键词： Li Stereochemical effects in mass spectra Studies on mass spectra of epimers of podophyllotoxin and its derivatives

Sequence Analysis of Polypeptide by Mass Spectrometry

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Chemical Research in Chinese Universities 1993年第4期9卷 288-295页

作者： YANG Hou-jun , LI Xiao-ling, HU Xiao-yu and chen yao-zu (State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou, 730000)

The method described in this work provides a sensitive and fast technique for investigating the primary structure of peptides with molecular weight up to 3340 amu. Usually, the metastable ion kinetic energy spectra (MIKES) and collisional activated decomposition (CAD) spectra provide complementary information for the FAB mass spectra, the MIKES and CAD spectra generally contain high-mass sequence ions.

关键词： Peptide Sequence analysis Mass spectrometry.

Studies on the mass spectrometry of natural products——V. Negative ion fast atom bombardment and collisional activation mass spectrometry in the structural analysis of oligoglycosides

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Chinese Journal of Chemistry 1987年第3期5卷 236-241页

作者： chen Neng-Yu chen Ning LI Hong chen yao-zu* ZHAO Fang-Zhi, Department of Chemistry, Lanzhoa University, Lanzhouchen Chang-Xiang YANG Chong-Ren, Kunming Institute of Botany, Academia Sinica, Kunming Department of Chemistry Lanzhou University Lanzhou Kunming Institute of Botany Academia Sinica Kunming

The negative ion fast atom bombardment （NFAB） mass spectrometry of eight glycosidescontaining one to three sugar units have been studied. The mass spectra of NFAB exhibit morepredominant quasi-molecular ions without adduct ions in the high mass region, which indicate moreunambiguously the molecular weights of the glycosides, than the positive ion FAB （PFAB） spectrado. Among the three matrix substances tested, glycerol, thioglycerol and PEG-200, the last one wasfound to give the best results. The characteristic ions of NFAB collisional activation CNFAB-CA)spectra of [M-H]- ions were more abundant and gave more definite information about sequences ofthe sugar units than the corresponding PFAB-CA spectra of [M+H]+ions.

关键词： FAB Studies on the mass spectrometry of natural products Negative ion fast atom bombardment and collisional activation mass spectrometry in the structural analysis of oligoglycosides

反相液相色谱中保留值变化规律的研究——同系物和柱温对保留值的影响

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化学学报 1998年第1期56卷 68-76页

作者：焦庆才刘茜陈耀祖南京大学生物科学与技术系南京210093 兰州大学化学系兰州730000

根据反相液相色谱保留模型和Martin方程,采用热力学方法导出了一组包括各种色谱参数(如柱温、流动相中有机改性剂浓度以及溶质、溶剂和键合相表面烷基配体中的碳数)的线性保留方程.利用这组方程能够解释反相液相色谱中各种线性保留规律... 详细信息

根据反相液相色谱保留模型和Martin方程,采用热力学方法导出了一组包括各种色谱参数(如柱温、流动相中有机改性剂浓度以及溶质、溶剂和键合相表面烷基配体中的碳数)的线性保留方程.利用这组方程能够解释反相液相色谱中各种线性保留规律和实验现象,并预测和实验验证了多种文献未报道的线性规律.

关键词：反相液相色谱保留模型保留值柱温

Diterpenoids from Rabdosia nervosa

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Acta Chimica Sinica English Edition 1989年第6期7卷 549-553页

作者： chen yao-zu BAI Guang MENG Xian-Jun Department of Chemistry Lanzhou UniversityLanzhou

Six ent-kaurene type diterpenoids have been isolated from the leaves of Rabdosia nervosa. Among them, ganervosin A and B were new compounds, the structures of which were elucidated as 1 and 2 respectively by spectral and chemical methods. The other four were identified as odonicin (3), novelrabdosin (4), nodosin (5) and shikokianal acetate (6), Compounds 5 and 6 were for the first time isolated from this herb.

关键词： Co Diterpenoids from Rabdosia nervosa Wang EtOH

A DNMR study on the ring inversion of oxazolidines

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Chinese Journal of Chemistry 1990年第5期8卷 430-434页

作者： YANG,Li The National Laboratory on Applied Organic Chemistry,Lanzhou University,Lanzhou 730000GAO,Kun KONG,Su-Ling chen,yao-zu Department of Chemistry,Lanzhou University,Lanzhou 730000 National Laboratory on Applied Organic Chemistry Lanzhou University Lanzhou 730000 Department of Chemistry Lanzhou University Lanzhou 730000

Ring inversion of eight substituted 2-phenyl-4,4-dimethyloxazolidines in o-dichloro- benzene-d_4 was studied by ~H *** high inversion barriers((?)G_c(?)=86.7—93.4 kJ·mol^(-1)) were found for these oxazolidine *** magnitude of the inversion barrier is dependent on the polarity of the substituent on the phenyl group.A linear correlation is present between the (?)G_c(?) of the inversion and the substituent constant,σ^+,of the substituent.

关键词： ring A DNMR study on the ring inversion of oxazolidines