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The Formal Stereoselective Synthesis of(+)-Preussin

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Chinese Chemical Letters 1997年第8期8卷 693-694页

作者： Dong, HQ Lin, gq CHINESE ACAD SCI SHANGHAI INST ORGAN CHEMSHANGHAI 200032PEOPLES R CHINA

The stereoselective synthesis of (+)-preussin has been achieved by utilizing the Sharpless asymmetric epoxidation of the divinylcarbinol (3) and the oxidative cyclization of 9 with PDC as the key steps.

关键词： The Formal Stereoselective Synthesis of DMF 甲酰胺 Preussin

Expression of matrix metallo-proteinase-28 in human normal cytotrophoblast cells and a choriocarcinoma cell line,JEG-3

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Chinese Science Bulletin 2002年第9期47卷 732-736页

作者： Zhang, J Cao, YJ liu, WM Zhao, BS Zeng, gq Duan, EK Chinese Acad Sci Inst Zool State Key Lab Reprod Biol Beijing 100080 Peoples R China

There are striking similiarities present between the behavior of invasive placentaL cells and that of invasive cancer cells. Matrix metalloproteinases (MMPs) are one of the most important mediators. MMP-28, the new member of MMPs, was sequenced and identified recently. Expression of MMP-28 mRNA and protein in the cytotrophoblast cells and a choriocarcinoma cell line, JEG-3 cell, was conducted by zymography, RT-PCR and Northern blot. There is MMP-28 mRNA expression in both the cytotrophoblast cells and JEG-3 cells by RT-PCR. The activity of MMP-28 in cytotrophoblast cells was significantly weaker than that in JEG-3 (P < 0.01) by zymography. Furthermore, mRNA expression of MMP-28 was significantly stronger (P < 0.001) in JEG-3 than in human cytotrophoblast cells in a time-dependent way by Northern Blot. Our results suggest that MMP-28 may play a role in some of the tissue-remodeling events associated with normal pregnancy and tumor progression.

关键词： cytotrophoblast cell choriocarcinoma cell line JEG-3 matrix metalloproteinases MMP-28.

Eremophilenolides from Cacalia Roborowskii

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Chinese Chemical Letters 1998年第1期9卷 65-68页

作者： Zhang, SM Zhao, GL Lin, gq Chinese Acad Sci Shanghai Inst Organ Chem Shanghai 200032 Peoples R China

From the extracts of the roots of Cacalia roborowskii (Maxim) Ling, five new eremophilenolides were isolated and their structures identified as 8 beta, 10 beta-dihydroxy-6 beta-methoxyleremophilenolide (1), 3 beta-acetoxyl-8 beta, 10 beta -dihydroxy-6 beta-methaxyeremophilenolide (2), 3 beta-angeloyloxy-8 beta-, 10 beta-dihydroxy-6 beta-methoxyeremophilenolide (3), 3 beta-(2-methylbutyryloxy)-8 beta, 10 beta-dihydroxy-6 beta-methoxyeremophilenolide (4), and 8 beta-hydroxy-6 beta-methoxyeremophil-7(11), 9-dien-8, 12-olide(5), based on 1D and 2D NMR experiments.

关键词： eremophilenolide root herb Cacalia roborowskii (maxim) Ling

Microbial-chemical routes to R and S-denopamine a useful drug for congestive heart failure

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Chinese Journal of Chemistry 1995年第5期13卷 475-480页

作者： Gu, JX Li, ZY Lin, gq CHINESE ACAD SCI SHANGHAI INST ORGAN CHEMSHANGHAI 200032PEOPLES R CHINA

Both enantiomers of denopamine were synthesized using microbial-chemical approach via bioreduction of 1-(acetoxyphenyl)ketone 4(R=CH2Cl) and 5(R=CO(2)Et) with fungus Geotrichum sp. G38.

关键词： denopamine bioreduction Geotrichum sp G38 asymmetric synthesis

TWO　NEW　PHENYLPROPANOID　GLYCOSIDES　FROM　CARYOPTERIS　INCANA(THUNB.)MIQ

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Chinese Chemical Letters 1996年第5期7卷 445-448页

作者： Gao, JJ Han, gq Yang, L BEIJING MED UNIV NATL LAB NAT & BIOMIMET DRUGSBEIJING 100083PEOPLES R CHINA LANZHOU UNIV STATE KEY LAB APPL ORGAN CHEMLANZHOU 730000PEOPLES R CHINA

Abstract: Two new phenylpropanoid glycosides, incanosides A and B were determined as 3-hydroxy-4-methoxy-βphenylethyl α-L-rhamnopyranosyl(1→3)-β-D-glucopyranosyl(1→2)-6-O-feruloyl-β-D-glucopyranoside and 3-hydroxy-4-methoxy-β-phenylethyl α-L-rhanmopyranosyl (1→3)-β-D-ghucopyranosyl(1→2)-β-D-glucopyranoside, respectively.

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Mechanical Alloying Effect on the Structure of Fe-Al-(Si) Alloy

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Journal of Materials Science & Technology 1997年第3期13卷 219-222页

作者： Zhang, JQ Wu, BY Hu, Z Wang, gq SOUTHEAST UNIV DEPT MECH ENGNNANJING 210096PEOPLES R CHINA NANJING UNIV DEPT CHEMNANJING 210008PEOPLES R CHINA NANJING UNIV DEPT PHYSNANJING 210008PEOPLES R CHINA

The mechanical alloying effects on the structures of Fe71.3Al28.4(CeO2)(0.3) and Fe73.3Al9.8-Si-16.6(CeO2)(0.3) samples have been investigated mainly by Mossbauer spectroscopy and X-ray diffraction. it is found that with the increase of milling time, a substituting disordered alpha-Fe solution is formed gradually and almost completed after milled for 72 h. Further increasing milling time causes the atomic rearrangement within the powders. Correspondingly, the average lattice parameter and average crystalline size change until 72 h and remain constant after 72 h. The addition of Si leads to the higher disordered degree reflected in the smaller average hyperfine field and larger mean square deviation.

关键词： Iron alloys

A Numerical Model for Typhoon Surges

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China Ocean Engineering 1998年第2期13卷 191-202页

作者： Pan, JN Wang, HC Yao, gq Nanjing Hydraul Res Inst River Harbour Dept Nanjing 210024 Peoples R China

In this paper a simple and efficient implicit finite-difference scheme is used for depth-averaged two-dimensional storm surge model. This finite-difference scheme is simpler and more efficient than the widely-used ADI scheme. Accuracy analysis and stability analysis indicate that the scheme has two-order accuracy and is unconditionally stable when the grid size is constant. The present analysis results show that the scheme is of higher numerical accuracy than that introduced by Maa (1990). After tested by ideal models, a calculation example of a real typhoon surge is carried out, the results of the numerical simulation coincide well with the observed data and the accuracy is sufficient for engineering applications.

关键词： storm surge numerical simulation finite-difference scheme accuracy stability

Solid and liquid phase equilibria in mixtures of N, N-dimethylacetamide with chlorinated hydrocarbons

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Chinese Science Bulletin 1997年第11期42卷 918-921页

作者： Che, gq Peng, WL Che, B Department of Chemistry Zhongshan University Guangzhou China

IN refs.[1,2],we studied the solid and liquid phase equilibria in mixtures of tetra-chloromethane with oxygen and nitrogen-containing compounds,intermolecular interactionswith the formation of solid molecular addition... 详细信息

关键词： phase diagram solid and liquid equilibrium N N-dimethylacetamide.

A New Approach to the Construction of Pyrrolizidine and Indolizidine Skeleton: Enantioselective Synthesis of (1S, 7aS)-1-hydroxypyrrolizidine and (1S, 8aS)-1-hydroxyindolizidine

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Chinese Chemical Letters 1997年第9期8卷 773-776页

作者： Dong, HQ Shi, ZC Lin, gq CHINESE ACAD SCI SHANGHAI INST ORGAN CHEMSHANGHAI 200032PEOPLES R CHINA

A new approach to the construction of pyrrolizidine and indolizidine skeleton was described. By employing this cyclization method the synthesis of (1S. 7aS)-1-hydroxypyrrolizidine (1a) and (1S. 8aS)-1-hydroxyindolizidine (1b) was achieved by treatment of the trimesylate 6a or 6b with aqueous ammonia in the presence of KaCO(3) (or Cs2CO3) in one-pot fashion.

关键词： ppm HRMS A New Approach to the Construction of Pyrrolizidine and Indolizidine Skeleton hydroxyindolizidine hydroxypyrrolizidine and Enantioselective Synthesis of