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151.
Jun Gui DAI Meng ZHANG Min YE Wei Hua ZHU Ji Yu GUO Xiao Tian LIANG* Institute of Materia Medica Chinese Academy of Medical Science & Peking Union Medical College Beijing 《中国化学快报》2003,14(8)
Sinenxan A, 2a, 5a, 10b,14b-tetraacetoxy-4(20),11-taxadiene, is a taxoid isolated from the callus cultures of Taxus spp. in high yield (ca. 1~2% of dry weight)1,2. The rich resources and its taxane-skeleton vest it valuable potential for the semisynthesis of paclitaxel or other structurally related bioactive compounds, such as 搒econd -generation?taxoid anticancer agents and taxane-based multidrug resistant anticancer agents3-5. Many remarkable studies on its structural modification by chemi… 相似文献
152.
Zhi Hua MA Cong LIU Yong Hua ZHAO Wei LI Jian Bo WANG* Key Laboratory of Bioorganic Chemistry Molecular Engineering of Ministry of Education Department of Chemical Biology College of Chemistry Peking University Beijing 《中国化学快报》2002,13(8)
b-Amino acids and their derivatives have attracted considerable attention in recent years due to their occurrence in biologically active natural products, such as dolastatins 11, cyclohexylnorstatine 22 and taxol 33. bAmino acids also find application in the synthesis of blactams4, piperidines5, indolizidines6. Moreover, the peptides consisting of bamino acids, the so called bpeptides, have been extensively studied recently7. Consequently, considerable efforts have been directed to the synt… 相似文献
153.
JIAO Qing ze ZHAO Yun LI Xiao dan EVANS D. G. DUAN Xue * Key Laboratory of Science Technology of Controllable Chemical Reactions Ministry of Education Beijing University of Chemical Technology Beijing P. R. China 《高等学校化学研究》2002,18(2)
IntroductionGlycolethersareimportantindustrialderivativesofepoxides .Polyethylene glycolethylethersandpolypropyleneglycolethylethersaretwoimportantseriesofproducts .Glycolethersaregoodsolventsduetothepresenceof—O—and—OH groups.Asare sult ,theyarewidelyuse… 相似文献
154.
Aldimines are an important class compounds1 which can be prepared by selective deoxygenation of nitrones. Thus more attention was paid to the selective deoxygenation of nitrones in organic synthesis. The reducing reagents, include low-valent titanium2, acetic formic anhydride3, sodium hydrogen telluride4, tributyltin hydride4, terathiomolybdate5, metallic indium in aqueous media6, zinc-aluminum trichloride7, aluminum iodide8, triphenylphosphine9, etc. However, there are various limitations … 相似文献
155.
Zhi Hong JIA Hai Quan SU Shou Hua FENG Chun Shan SHI* Key Laboratory of Rare Earth Chemistry Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Key Laboratory of Inorganic Hydrothermal Synthesis 《中国化学快报》2001,(11)
Perovskite complex fluorides have attracted great interests due to their particular physical properties such as antiferromagnetic characteristics1, photoluminescence behavior2. Complex fluorides are usually prepared by solid state reactions at high-temperature. In spite of inert atmosphere, it is inevitable to contain a bit of oxygen. This has great effect on the luminescent character of rare earth ions. There are also reports about synthesizing some binary fluorides by high-temperature hy… 相似文献
156.
Rong Wei TENG Hai Zhou LI Xue Mei ZHANG Xi Kui LIU De Zu WANG Chong Ren YANG* Kunming Institute of Botany Chinese Academy of Sciences Kunming 《中国化学快报》2001,(3)
In our continuing research works on Panax notoginseng (Burk.) F. H. Chen, a famous traditional Chinese herb medicine1, two new dammarane glycosides named notoginsenosides T1 (1) and T2 (2) were isolated from the mild acid hydrolysis products of the root saponins. We report herein the structure elucidation of these two novel glycosides.Notoginsenosides T1(1) was obtained as white solid, [(] = +14.49 (0.50, MeOH). Its negative mode HR-FAB-MS spectrum showing the quasimolecular ion peak a… 相似文献
157.
Qiao Hong CHEN Feng Peng WANG* Department of Chemistry of Medicinal Natural Products School of Pharmacy West China University of Medical Sciences Chengdu 《中国化学快报》2001,(5)
Lappaconitine 1, a bisnorditerpenoid alkaloid, was isolated from many plants of Aconitum species such as A. barbatum var. pulerulum and A. sinomontanum (Ranunculaceae)1-3, and used clinically for treatment of analgic disease as a nonaddicted drug in China4, and as an antiarrythmic in Uzbekistan5. In order to search for high activity, low toxicity compounds, we have carried out the structure modifications of lappaconitine. In this case, an attempt to induce the oxygenated group at C-10 in 1 b… 相似文献
158.
Rui WU Qi YE Neng Yu CHEN Guo Lin ZHANG* Chengdu Institute of Biology the Chinese Academy of Sciences Chengdu Department of Chemistry Chemical Industry Lanzhou University Lanzhou Technical Centre Hua Sheng Group Co. L 《中国化学快报》2001,(3)
The plant Miliusa balansae Finet et Gagnep. is used in Chinese folk medicine for different symptom such as gastropathy and glomerulonephropathy. There is no report about its chemical investigation. In this study a new norditerpene with novel skeleton, named miliusate (1) was isolated, and its structure was established by spectral evidence.Compound 1 was obtained as white flaky crystal, mp 89-91(C; Its molecular formula C20H26O5 was provided by quasi-molecular ion [M+H]+ at m/z 347.17970 (c… 相似文献
159.
Xue Qiang YIN Guang Zhong YANG Yuan Chao LI* Shanghai Institute of Materia Medica Chinese Academy of Sciences Shanghai 《中国化学快报》2001,(7)
The diterpenoid triexpoxides lactone triptolide is a potent antileukemic, antiflammatory, immunosuppressive and antifertile principle of Tripterygium wilfordii Hook f.1,2. Many methods of synthesis of this compound have been reported in which trans-3,3b,4,9b,10, 11-hexahydro-6-methoxy-9b-methyl-7- (1-methylethyl) phenanthro {1,2-c [furan-1,5- dione]} 4 was an important intermediate. In one reported synthesis, compound 4 was obtained by CrO3/AcOH oxidation of triptophenolide methyl ether 1, b… 相似文献
160.
Yang JIANG Bo TAN Yu Fen ZHAO* The Key Laboratory of Bioorganic Phosphorus Chemistry Ministry of Education Department of Chemistry School of Life Sciences Engineering Tsinghua University Beijing 《中国化学快报》2001,(9)
Mass spectrometry plays an important role in peptide sequencing since the invention of soft ionization techniques, such as fast atom bombardment (FAB), electrospray (ESI) and matrix-assisted laser desorption/ionization (MALDI). In our previous work, it was found that phosphorylation on the N-terminal of small peptides could enormously improve their sensitivity in FAB-MS1.To understand the sensitivity-improvement effect of phosphoryl group, the energies for the protonation of glycylglycin… 相似文献