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FIRST SYNTHESIS OF(±)-3-[(5-HYDROXY)HOMOGERANYL]-△~2-BUTENOLIDE

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Chinese Chemical Letters 1996年第4期7卷 303-304页

作者： Jin QU Wei Dong LI Jing LI Yu Lin LI(State Key Laboratory of APPlied Organic Chemistry and Institute of Organic Chemistry, lanzhou university, lanzhou 730000) State Key Lab. of Appl. Organ. Chem. Institute of Organic Chemistry Lanzhou University Lanzhou 730000

A new farnesane-based sesquiterpene lactone, 3- [(5-hydroxy) homogeranyl]-△2-butenolide, was synthesized for the first time starting from trans, trans-farnesol through five steps in an overall yield of 6. 4 % as its ... 详细信息

关键词： FIRST BUTENOLIDE

CONVERSION OF ACETALS AND KETALS TO CARBONYL COMPOUNDS PROMOTED BY ZrCl_4-NaBH_4

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Chinese Chemical Letters 1991年第1期2卷 47-50页

作者： Shao Zu WU Hui Dong WANG Ning CHENG Department of Chemistry,lanzhou university.lanzhou,730000

In our study on the chemistry of ZrCl_4-NaBH_4,we have found that aldehydes and ketones can be regenerated from acetals and ketals at 30℃ in Et_2O in high yield The reaction mechanism was discussed.

关键词： MS GC CONVERSION OF ACETALS AND KETALS TO CARBONYL COMPOUNDS PROMOTED BY ZrCl4-NaBH4

STUDIES　ON　THE　PRENYLFLAVONOIDS　PART　Ⅹ：THE　TOTAL　SYNTHESIS　OF　ANTIARONE－C　AND　ANTIARONE－H

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Chinese Chemical Letters 1994年第11期5卷 935-938页

作者： Yu Lin LI Lian Ye ZHAO(State Key Laboratory of Applied Organic Chenistry,lanzhou university,lanzhou,730000)

Antiarone-H, 3′, 5, 7-trihydroxy- 2′,6-di(γ,γ-dinethylallyl)-4′-methoxyflavanone,has been synthesied by the prenylation of 2-hydroxy-4,6-dimethoxymethoxyacetophenone follouwed by rearrangement,condensation with 4-methoxy-3-hydroxy-2-(γ,γ-dimethylallyl) benzaldehyde,cyclization and ***-C has been prepared by two route st the same time.

关键词： TOTAL SYNTHESIS OF AND ANTIARONE

STUDIES ON SYNTHESIS OF GIBBERELLIN II——PARTIAL SYNTHESIS OF GIBBERELLIN A_5 METHYL ESTER

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Chinese Science Bulletin 1989年第22期34卷 1932-1933页

作者：赵河潘鑫复 Institute of Organic Chemistry Lanzhou University Lanzhou 730000 PRC

Gibberellin A5 （GA5）（9） is a C19-gibberellin which was originally isolated from Phaselous mutiflorus in 1960 by MacMillan et al. This letter reports the synthesis of Gibberellin A5 methyl ester（8） from Gibberel... 详细信息

关键词： originally letter quantitatively giving 二尹 acetoxy anhydride totally ketone substituted

THE SAND WEDGE AND MIRABILITE OFTHE LAST ICE AGE AND THEIR PALEOCLIMATICSIGNIFICANCE IN HEXI CORRIDOR

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Chinese Geographical Science 2001年第1期11卷 80-86页

作者： HU Gang, WANG Nai-ang (School of Resources and Environment, lanzhou university, lanzhou 730000, P. R. China Cold and Arid Regrons Environment and Engineering Research Institute, the Chinese Academy of Scienes, lanzhou 730000, P. R. China) School of Resources and Environment Lanzhou University Lanzhou P. R. China Cold and Arid Regrons Environment and Engineering Research Institute the Chinese Academy of Sciences Lanzhou P. R. China

The sand wedges in Hexi Corridor occur in the alluvial gravel stratum of bajada and high terraces. The 14C ages of eolian sand in sand wedges prove that they formed during the Last Ice Age, with the mean annual air temperature about ? 5.6°C. The common 14C and AMS 14C dating ages of terrestrial branch relicts in Huahai clay-mirabilite interlayer are (11 600 ± 280) a B. P. and (1118 ± 54) a B. P. respectively, proving that the mirabilite formed at the cold episode of the Last Glacial Maximum(LGM) and Younger Dryers(YD) in Huahai Lake. It is pointed out that the mean annual air temperature in Hexi Corridor during LGM was about ?3°C – ?7°C, 11°C – 15°C lower than that of present, and that during YD was about 0°C – 2°C, 6°C – 8°C lower than at present. This decreasing temperature values are generally coincident with those inferred by pollen, sand wedge and ice core in the northern China, and also with the research on temperature-falling amplitude of middle and high latitude on the Northern Hemisphere recently.

关键词： sand wedge Last Ice Age Hexi Corridor paleoclimate

A novel system for Agrobacterium-mediated transformation of wheat(Triticum aestivum L.) cells

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Cell Research 1993年第1期3卷 49-60页

作者： XU YAO, BAOJIAN LI, JINGFEN JIA Biotechnology Research Centre,Zhongshan university, Guangzhou 510275. Department of Biology, lanzhou university, lanzhou 730000, China. Department of Biology Lanzhou University Lanzhou 730000 China.

A new approach for transforming the cultured cells of wheat(Triticum aestivum L. cv. Ganmai 8) was developed using Agrobacterium tumefaciens. The features of the optimum procedure were: (a) both combined synthetic signal molecules and multiple natural extracts from susceptible plants were used to pretreat the primary vigorous Agrobacterium(PVA) cells for approximately 16 h; (b) the gyratory magnetic field condition was used during cocultivation; (c) the cocultivating period and selecting condition were modified; (d) the recipient cells were at exuberant metabolism and active division while infected with Agrobacterium. Both neomycin phosphotransferase and nopaline synthase assays demonstrated the expression of NPT Ⅱ and NOS genes, located on the T-DNA segment of chimaeric plasmid pGV3850::1103neo, in transformed wheat cell colonies by adopting the techniques of dot blot, ndPAGE or high voltage paper electrophoresis. Integration of the foreign genes into wheat genome was confirmed by Southern blot hybridization. Moreover, a relatively rational method was described for the estimation of transformation frequencies from cultured cell levels.

关键词： genetic engineering gyratory magnetic field natural susceptible extracts synthetic signals transformation system wheat cells.

NEW SESQUITERPENE FROM LIGULARIA SAGITTA

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Chinese Chemical Letters 1995年第10期6卷 875-876页

作者： Li YANG Hai Ruo PENG Zhong Jinng JIA(Institute of Organic Chemistry, State Key Laboratory of Applied Organic Chemistry,lanzhou university, lanzhou,730000)(Author to whom correspondence should be addressed.) lanzhou Univ Inst Organ Chem State Key Lab Appl Organ Chem Lanzhou 730000 Peoples R China

A new eremophilane acid was isolated in the phytochemical investigation of the roots of Ligularia. sagitta. Its structure and stereochemistry were elucidated by ID NMR and 2D NMR techniques including H-1-H-1 COSY, C-1...

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Theory of truth degrees of propositions in the logic system Ln^＊

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Science in China(Series F) 2006年第4期49卷 471-483页

作者： LI Jun1,2 & WANG Guojun1,3 1. Institute of Mathematics, Shaanxi Normal university, Xi’an 710062, China 2. School of Sciences, lanzhou university of Technology, lanzhou 730050, China 3. Research Center for Science, Xi’an Jiaotong university, Xi’an 710049, China 1. Institute of Mathematics Shaanxi Normal University Xi’an 710062 China 2. School of Sciences Lanzhou University of Technology Lanzhou 730050 China 3. Research Center for Science Xi’an Jiaotong University Xi’an 710049 China

By means of infinite product of uniformly distributed probability spaces of cardinal n the concept of truth degrees of propositions in the n-valued generalized Lu- kasiewicz propositional logic system Ln^＊ is introduced in the present paper. It is proved that the set consisting of truth degrees of all formulas is dense in [0,1], and a general expres- sion of truth degrees of formulas as well as a deduction rule of truth degrees is then obtained. Moreover, similarity degrees among formulas are proposed and a pseudo-metric is defined therefrom on the set of formulas, and hence a possible framework suitable for developing approximate reasoning theory in n-valued generalized Lukasiewicz propositional logic is established.

关键词： truth degree similarity degree approximate reasoning.

A Facile Synthesis of 3-Oxo-7αH-eudesma-4-ene-9β, 12-diol

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Chinese Chemical Letters 1998年第7期9卷 625-627页

作者： Li Jun LIU Yong Gang CHEN Zhao Ming XIONG Jiang LI Gang ZHOUand Yu Lin Li(National Laboratory of Applied Organic Chemistry and Institute of Organic Chemistry, lanzhou university, lanzhou 730000)(Ningxia Medical College, Yinchuan 750001) lanzhou Univ Natl Lab Appl Organ Chem Lanzhou 730000 Peoples R China lanzhou Univ Inst Organ Chem Lanzhou 730000 Peoples R China Ningxia Med Coll Yinchuan 750001 Peoples R China

A facile ndxture of the C-11 isomeric 3 - oxo-7αH-eudes ma-4-en- 9β, 1 2-diol has been achieved ffom oxycarvone. The C-11 configuration of natural product is established through comparison of IHNMR spectra between ... 详细信息

关键词： Synthesis Sesquiterpenoid 3-oxo-7αH-eudesma-4-en-9β 12-diol oxycarvone