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排序方式: 共有631条查询结果,搜索用时 15 毫秒
561.
Ke Chun ZHANG Lei LIU Ting Wei MU Qing Xiang GUO* Department of Chemistry University of Science Technology of China Hefei 《中国化学快报》2000,11(11)
The molecular recognition of cyclobis(paraquat-p-phenylene), 14+, has drawn great attention recently, due to its important applications in the design and synthesis of electrochemically and chemically switchable rotaxanes, photoactive rotaxanes, and other molecular devices1. Usually, this type of molecular recognition was investigated with the methods including X-ray, NMR, UV, and IR. However, since these methods usually have difficulties in providing a detailed understanding of the energeti… 相似文献
562.
Li Qiao Yu Zhi Zhou Huan Chen Jia Qing Cao Yue Hu Pei~* School of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Shenyang China 《中国化学快报》2008,19(3):299-301
Cunninghamella elegans has been employed for the biotransformation of cinobufagin (1) to afford one metabolites. The structure of the transformation product has been characterized as 7β,12β-dihydroxylcinobufagin (2). Product 2 is a new compound. In vitro cytotoxic activities of the biotransformation product and the substrate-cinobufagin have been assayed against HeLa; they all showed cytotoxic activities. 相似文献
563.
1 INTRODUCTIONCu(I)complexeswithphosphineandarsineligandsarewellknown〔1〕.ForCuphosphinecomplexes,theCu∶ligandratiovariesfrom1∶1to1∶4andcoordinationgeometryofCu(I)rangesfromlineartotrigonal,thentotetrahedralextremes;forexample,the1∶2adductsCu(PPh3)… 相似文献
564.
Yu Fen LüLiang Fang Zhu Qiu Yuan Liu Bin Guo Xiao Ke Hu Chang Wei Hu~* Key Laboratory of Green Chemistry Technology Ministry of Education College of Chemistry Sichuan University Chengdu PR China 《中国化学快报》2009,20(2):238-240
The liquid-phase direct catalytic amination of benzene to aniline was performed in acetic acid water solvent using a series of vanadium(Ⅲ,Ⅳ,Ⅴ)complexes with N,O-or O,O-ligands as catalysts and hydroxylamine hydrochloride as the aminating agent. The vanadium complexes exhibited much higher selectivity towards the production of aniline than NaVO_3 or VOSO_4.Under the optimized conditions,an aniline yield of 42.5%and a TON of 48 with a high selectivity of above 99.9%was obtained using 0.2 mmol of[VO(OAc)_2]... 相似文献
565.
Qian ZHANG Ying CHEN Yun Hong ZHENG Wan Yun SHENG Peng XIA* Yi XIA Zheng Yu YANG Kuo Hsiung LEE Department of Organic Chemistry The School of Pharmacy Shanghai Medical University Yi Xue Yuan Road Shanghai Natural Products 《中国化学快报》2001,(1)
Interesting biological activities have been reported recently for 4-methylhydro-2H-pyrano [6,5-h]-chromen-2-ones and 4-methylhydro-2H-pyrano[6,5-h]quinolin-2-ones, including excellent anti-HIV activity with DCK derivatives1 and significant cytotoxic activity with 4,8,8-trimethylhydro-2H-pyrano[6,5-h]quinolin-2-one2. These results prompted us to synthesize two series of corresponding diaza three-ring heterocyclic analogs, trihydro- pyridino[2,3-h]quinolin-2-ones and hydropyridino[2,3-h]quino… 相似文献
566.
Yang Hong GUO Zhan SHI Ding HONG Ya Bo WEI Wen Qin PANG* Key Laboratory of Inorganic Synthesis Preparative Chemistry Department of Chemistry Jilin University Changchun 《中国化学快报》2001,(4)
The chemistry of titanium phosphates has attracted considerable interests because of their applications in ion exchange, redox catalysis and outstanding non-linear optical materials. However, only a few titanium compounds have been reported, and fewer reports deal with single-crystal structure determinations due to the difficulty in obtaining large single crystals of titanium phosphates. The synthesis of titanium phosphates often leads to two-dimensional layered phases1-3, and several titanium… 相似文献
567.
Na LI Xin LIU Mao LIN* Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College Xian Nong Tan Street Beijing 《中国化学快报》2001,(10)
Various biological activities of stilbenoids have been described, such as antifungal and antibacterial activities1, antihepatotoxic activity2-4, anti-HIV activity5. Stilbenoids mainly existed in Vitaceae, Diperocarpaceae, Gnetaceae, Cyperaceae, Leguminase1. Many oligostilbenes have been isolated from Vitaceaeous plants. But, there was no report on the stilbenoids in Ampelopsis sinica (Miq.) W. T. Wang which was traditionari- ly used to treat arthritis6. In our study on the constituen… 相似文献
568.
Zhi NA Shuang Xi MEI Chao Ming LI Zhong Wen LIN Han Dong SUN* Laboratory of Phytochemistry Kunming Institute of Botany Chinese Academy of Sciences Kunming 《中国化学快报》2001,(3)
Isodon enanderianus (Hand.-Mazz.) H. W. Li, a perennial shrub plant of Labiatae family, is widely distributed in the southern part of Yunnan province. It has long been used as folk medicine to diminish inflammation and detoxify1. The Isodon genus is known to be rich in ent-kaurane diterpenoids, a series of new ent-kaurane diterpenoids have been isolated from the dried leaves of I. enanderianus2-4. During the course on a re-investigation of the chemical constituents of I. enanderianus, four… 相似文献
569.
Qiang CHEN Ying GUAN Xian Min ZHANG Yu Xing PENG Jian XU* State Key Laboratory of Polymer Physics & Chemistry Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences Beijing Chengdu Institute of Organic Chemi 《中国化学快报》2001,(11)
Polymer gels are of considerable interests in material science1-3. Many theoretical and experimental studies have been made on the cross-linking copolymerization4-6 of these systems. Recently, in situ interferometry is applied in studying this process7-9. As shown in Figure 1, the common two-armed cross-linkers will lead to defects in the network, while multi-armed cross-linkers will enhance the integrity of the network. This paper studies the cross-linkers influence on cross-linking and t… 相似文献
570.
Guo Jun ZHENG Jian Jun WANG Tian Rui REN Liu YANG Wan Ru SUN* State Key Laboratory of Microbial Resources Institute of Microbiology CAS Beijing Laboratory of Chemistry Computer Institute of Chemical Metallurgy CAS Beijing 《中国化学快报》2001,(4)
Large amount of facts indicated that enantiomers were different from each other in biological activity, physiological activity and toxicity in clinical applications1. It resulted in the increase of interest on preparation of chiral drugs. Optical active 3-phenylglycidic ester, especially (2R,3S)-methyl 3-phenylglycidate is an important starting material for production of many chiral drugs, such as taxol, (2R,3S)-diltiazem etc2,3.For the above purpose, a series of lipases were screened. Final… 相似文献