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711.
Ying Hong WANG Kai Sheng HUANG Mao LIN* Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 《中国化学快报》2000,11(12)
Continuous investigation on oligostilbenes from the lianas of Gnetum hainanense resulted in the isolation of a new rhapontigenin dimer, Gnetuhainin P (1), in addition to the dimers of resveratrol and oxyresveratrol reported previously1. Gnetuhainin P (1) was obtained as a yellowish amorphous powder, [(]25D +6.6 (c 0.092, MeOH). The high resolution FABMS m/z 533.1866 [M+H]+ gave a molecular formula of C30H28O9 (C30H29O9 requires 533.1812), which corresponds to a isorhapontigenin dimer. … 相似文献
712.
Peng DIAO Min GUO Ru Ting TONG* Department of Chemistry Hebei Teacher''''s University Shijiazhuang Department of Traditional Chinese Pharmacy Traditional Chinese Medicine College Hebei Medical University Shijiazhuang 《中国化学快报》2000,11(12)
Interest in the properties of organized monolayers has grown enormously in recent years because these monolayers can provide a means to control the interface at a molecular level1. The self-assemblies of alkanethiols and their derivatives were probably the most intensively studied due to their stability, well-packed structure, ease in preparation, and flexibility in designing the tail group2. The adsorption kinetics of thiol monolayer has been studied by using several techniques, including con… 相似文献
713.
Xiao Mei WANG Qi FANG Chun WANG Guang Yong ZHOU Yan REN Min Hua JIANG* State key laboratory of Crystal Materials Shandong University Jinan 《中国化学快报》2001,(1)
Two-photon absorption (TPA) occurs through the simultaneous absorption of two photons via virtual states in a medium. Materials with large TPA cross section are gaining increasing attention recently due to their potential applications in optical data storage, two-photon up-converted lasing, two-photon-laser scanning fluorescence microscopy, optical power limiting and photodynamic therapy1-3. Numerous organic compounds have been investigated both experimentally and theoretically in order to u… 相似文献
714.
Ya Ping WANG Lu Ling WU Xiang HUANG* College of Chemical Engineering Zhejiang University of Technology Hangzhou Department of Chemistry Zhejiang University Xixi Campus Hangzhou 《中国化学快报》2001,(1)
Conjugated dienes are valuable intermediates in organic chemistry. Many biologically active compounds occurring in nature possess the structural skeleton of conjugated dienes such as chillea amide1 and pelltoine2. Besides, the synthesis of conjugated dienes for use in the Diels-Alder reaction is still an important challenge in organic synthesis. One particularly attractive approach has been the incorporation of heteroatom substituents that can activate the diene3.Recently, we found that β-br… 相似文献
715.
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
716.
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
717.
1 INTRODUCTIONCu(I)complexeswithphosphineandarsineligandsarewellknown〔1〕.ForCuphosphinecomplexes,theCu∶ligandratiovariesfrom1∶1to1∶4andcoordinationgeometryofCu(I)rangesfromlineartotrigonal,thentotetrahedralextremes;forexample,the1∶2adductsCu(PPh3)… 相似文献
718.
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
719.
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
720.
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