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991.
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
992.
Lin HE Xian Fu LIN* De Shui LV Zhi Chun CHEN Institute of Applied Chemistry of Zhejiang University Hangzhou 《中国化学快报》2001,(1)
Preparing the organized ultrathin film of proteins is the key to developing of protein-based molecular devices such as biosensors. In the past, the organized molecular layers were fabricated by the means of Langmuir-Blodgett (LB), which utilized the amphipathy of molecules. Molecular deposition (MD) which is based on the electrostatic interaction between the charged substrates and oppositely charged absorbate is a new and versatile method for preparing organized self-assembled ultrathin film… 相似文献
993.
Rui Yun GUO Jun Biao CHANG* Rong Feng CHEN Jing Xi XIE Da Yu YAN Henan Institute of Chemistry Zhengzhou Institute of Meteria Medica Chinese Academy of Medical Science Beijing The Graduate School of University of Science T 《中国化学快报》2001,(6)
Biphenyl units are present in a wide range of compounds both natural and synthetic, and many of them have pharmacological activity1. Xie Jingxi et al. found that dimethyl 4,4'-dimethoxy-5,6,5',6'-dimethylenedioxybiphenyl-2,2'-dicarboxylate((-DDB) as an important intermediate for the synthesis of Schizandrin C analogue which is effective in lowering elevated SGPT level2-3. Two isomers dimethyl 6,6'-dimethoxy-4,5,4',5'-dimethylenedioxybiphenyl-2,2'-dicarboxylate ((-DDB) and 6,4,-dimethoxy-4… 相似文献
994.
995.
Ji Shan WU Chun Yan CHI Xian Hong WANG* Xiao Jiang ZHAO Ji LI Fo Song WANG State Key Laboratory of Polymer Physics Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 《中国化学快报》2001,(5)
IntroductionFerrocene-containing compounds have been widely used as important probes to investigate the electron transfer/transport properties of the molecular materials1. Recently, this technique was employed in molectronics research, where the ferrocenes were incorporated on the ends of conjugated molecular wires, and the electron transfer/transport abilities of the molecular wires were conveniently studied by electrochemical method2. Ethynylferrocene and iodoethynylferrocene were two import… 相似文献
996.
Electrochemical oxidation of 3-methylcatechol as a model compound has been studied in the presence of 1,10-phenanthroline as a bi-dentate nucleophile in water/acetonitrile(70/30,v/v) solution using cyclic voltammetry and controlled-potential coulometry. The results revealed that anodically generated 3-methylcyclohexa-3,5-diene-1,2-dione participates in inter and intramolecular Michael addition reactions with 1,10-phenanthroline and via an ECEC pathway converts to the corresponding heterocyclic compound.The present work has led to the development of a facile and one-pot method with high atom economy under ambient conditions and in an undivided cell using a carbon electrode. 相似文献
997.
Tian Lan Xian Xia Yuan Jiang Hong Yu Chao Jia Yu Shi Wang Hui Juan Zhang Zi Feng Ma Wei Dong Ye 《中国化学快报》2011,22(3):253-255
Several 6-aminoquinoline derivatives,which could be used in drug design,have been synthesized.The reaction conditions were comparatively studied,and the p-chloroaniline was used as optimum oxidant in Skraup-Doebner-Von Miller reaction.The nitro group was reduced effectively by SnCl2 with no halo-removed occurred. 相似文献
998.
Yang Xiao Xiao Yan Zhang Qin Bo Wang Ze Tan Can Cheng Guo Wei Deng Zhi Gang Liu He Fei Zhang 《中国化学快报》2011,22(2):135-138
An attempt has been made to prepare terephthalic acid(TPA) by solvent-free oxidation of p-xylene(PX) with air over tetra(pchlorophenylporphinato) manganese chloride(T(p-Cl)PPMnCl) and cobalt acetate.The co-catalysis between T(p-Cl)PPMnCl and Co(OAc)2 has been discovered under solvent-free conditions.TPA yield could be increased significantly when T(p-Cl)PPMnCl and Co(OAc)2 were used together.The addition of T(p-Cl)PPMnCl into the reaction mixture over Co(OAc)2 significantly accelerated the rate-determining step of the oxidation process of PX to TPA.The effect of temperature on reaction was also investigated. 相似文献
999.
Sk.Khadeer Pasha V.S.V.Satyanarayana A.Sivakumar K.Chidambaram L.John Kennedy 《中国化学快报》2011,22(8):891-894
Several 2,5-dimethyl-N-substituted pyrroles were prepared by the condensation of different substituted anilines with 2,5- hexanedione using nano lead oxide as an efficient and recyclable catalyst.All the synthesized compounds are confirmed through IR, 1H NMR,13C NMR and mass spectral data.Nano lead oxide β-PbO(P85) was prepared by dissolving lead acetate dihydrate in 1- propanol at a pH 9.0 under stirring at 85℃.The structural study and surface morphology of the lead oxide(PbO) were characterized using X-ray diffraction(XRD),Scanning electron microscopy(SEM) and the functional groups of the PbO sample were investigated using infrared spectrophotometer. 相似文献
1000.
Treatment of chiral N-tert-butyl sulfinylimines with ethyl bromofluoroacetate in the presence of activated Zn dust in THF afforded the α-fluoro- β-amino acid derivatives in good yields(70-86%) and moderate diastereoselectivity(66:34-92:8). 相似文献