2004 Volume 15 Issue 5

Asymmetric Pictet-Spengler Reactions: Synthesis of Tetrahydroisoquinoline Derivatives from L-DOPA
Ye WANG , Zhan Zhu LIU , Shi Zhi CHEN , Xiao Tian LIANG
2004, 15(5): 505-507
[Abstract](208) [FullText HTML] [PDF 1142KB](2)
Abstract:
The cis-1-substituted-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid esters 3 can be obtained in a highly diastereoselective fashion through 1,3-induction Pictet-Spengler (P-S) cyclization of the L-DOPA (3,4-dihydroxyphenylalanine) methyl ester with aromatic or aliphatic aldehydes under acidic conditions. Their epimers 4 are also obtained as minor products.
An Efficient and Green Procedure for the Preparation of gem-Dicar-boxylates from Aldehydes Catalyzed by Fe2(SO4)3·xH2O
Ling Jun LI , Xin Ying ZHANG , Gui Sheng ZHANG
2004, 15(5): 508-510
[Abstract](212) [FullText HTML] [PDF 1035KB](0)
Abstract:
An efficient and environmentally benign conversion of aldehydes into the corresponding gem-dicarboxylates was realized by using hydrated ferric sulfate as a heterogeneous catalyst. In addition to its high efficiency, the catalyst can be recovered simply and reused efficiently for at least seven times.
Formation of α,α'-Bis(substituted benzylidene)cycloalkanones from Masked Aldehydes Promoted by Samarium(III) Triiodide
Xiao Xia WANG , Yong Min ZHANG
2004, 15(5): 511-514
[Abstract](295) [FullText HTML] [PDF 1388KB](0)
Abstract:
1,1-Diacetates 1 and N-[(1-benzotriazol-1-yl)alkyl]amides 2, both masked forms of aldehydes, could undergo deprotection and condensation with cycloalkanones in a one-pot procedure promoted by samarium(III) iodide (SmI3) to afford α,α'-bis(substituted benzylidene) cycloalkanones in good yields.
Synthesis and Characterization of a Novel Aqueous Dispersion Poly[urethane-(disperse blue 14)-urethane] Dye
Xian Hai HU , Xing Yuan ZHANG , Jia Bing DAI , Ge Wen XU
2004, 15(5): 515-517
[Abstract](214) [FullText HTML] [PDF 1039KB](0)
Abstract:
A novel polymeric dye of aqueous dispersion poly[urethane-(disperse blue 14)-urethane] was synthesized based on poly(propylene glycol) (PPG), 2, 4-tolylene diisocyanate (TDI), dimethylol propionic acid (DMPA), disperse blue 14 and triethylamine (TEA) depending on a modified acetone process. Fourier transform infrared spectroscopy (FTIR) was used to identify the structure of the polymeric dye, indicating an obvious carbonyl stretching absorption in disperse blue 14. The polymer was also characterized by the analysis of DSC, TGA, WAXD and UV-Vis spectroscopy.
An Efficient Preparation of 2, 3-Disubstituted Indole Derivatives Induced by Low-valent Titanium
Xue Sen FAN , Xin Ying ZHANG , Yong Min ZHANG , Gui Rong QU
2004, 15(5): 518-520
[Abstract](195) [FullText HTML] [PDF 1165KB](0)
Abstract:
An efficient synthesis of 2, 3-disubstituted indole derivatives through low-valent titanium induced reductive cyclization of acylamido carbonyl compounds is described.
Synthesis and Characterization of a Novel Biomaterial: Maleic Anhydride-modified Poly(dl-lactic acid)
Yan Feng LUO , Yuan Liang WANG , Xu Feng NIU , Jun PAN , Liang Ping SHI
2004, 15(5): 521-524
[Abstract](200) [FullText HTML] [PDF 1143KB](3)
Abstract:
A novel modified poly(dl-lactic acid) (PDLLA) was obtained by covalently grafting of maleic anhydride onto the backbone of PDLLA, attempting to improve PDLLA's hydrophilicity and cell affinity and to provide reactive groups for further chemical modification. FTIR, 13C NMR and DSC were used to characterize the maleic anhydride-modified PDLLA.
Synthesis and Color-tunable Fluorescence Properties of Schiff Base Zinc (II) Complexes Used as Electroluminescent Materials
Yi YI , Xiao Qiang WEI , Ming Gui XIE , Zhi Yun LU
2004, 15(5): 525-528
[Abstract](222) [FullText HTML] [PDF 1458KB](0)
Abstract:
Four kinds of bis(N-alkylsalicylaldiminato) zinc(II) complexes were synthesized, and their molecular structures were determined by FT-IR and elemental analysis. Their photoluminescence properties were determined, which indicated that they could emit strong fluorescence varying from blue to yellow to reddish orange depending on their different molecular structures. They had good thermostability, solubility and film forming capability, and can be used as organic electroluminescent materials. These new complexes may afford the feasibility to realize full-color display with materials based on similar molecular structures.
Dioxygen Affinities and Biomimetic Catalytic Oxidation Performance of Transition-metal Complexes with Unsymmetrical Bis-Schiff Bases
Xing Yao WEI , Jian Zhang LI , Ying DU , Sheng Ying QING
2004, 15(5): 529-531
[Abstract](186) [FullText HTML] [PDF 1160KB](0)
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The oxygenation constants and thermodynamic parameter (ΔΔHo, ΔSo) of Co (II) complexes with unsymmetrical bis-Schiff baeses were measured and their Mn(III) complexes as models of mimicking monooxygenase were employed to catalyze epoxidation of styrene. The effect of substituent R in a salicylidene of ML1~ML4[M=Co (II), Mn (III)Cl] on the dioxygen affinities and biomimetic catalytic oxidation performance were also investigated. Among them, the MnL4Cl containing a pendant benzoaza crown ether ring showed highest conversion and selectiviy up to 54.9% and 96.9% respectively.
Synthesis of RGD-aPEG-lactoside, a Potential Anti-metastasis Glycoconjugate
Shu Chun LI , Li Min NIU , Hui LI , Zhong Jun LI , Qing LI
2004, 15(5): 532-534
[Abstract](185) [FullText HTML] [PDF 984KB](0)
Abstract:
The adhesive interaction between tumor cells and host cells or the extra cellular matrix plays a crucial role in metastasis. Due to the anti-metastasis effects of RGD (arginyl-glycyl-aspartic acid) and some oligosaccharides, RGD-aPEG-Lactoside was prepared which will be used on anti-metastasis.
Synthesis of Quinolone Analogues: 7-[(2S, 4R)-2-Aminomethyl-4-hydroxypyrrolidin-1-yl] Quinolones
Jiu Yu LIU , Hui Yuan GUO
2004, 15(5): 535-538
[Abstract](174) [FullText HTML] [PDF 1111KB](1)
Abstract:
New quinolone derivatives of 7-[(2S, 4R)-2-aminomethyl-4-hydroxypyrrolidin-1-yl] quinolone-3-carboxylic acids were synthesized by condensation of 7-halo substituted quinolone-3-carboxylic acids with (2S, 4R)-2-aminomethyl-4-hydroxypyrrolidine. These compounds were characterized by FAB-MS and 1H NMR.
Two Novel Sub-skeleton Types of ent-Kauranoids from Isodon gesneroides
Shao Nong CHEN , Shao Yuan CHEN , Han Dong SUN , Wen Zhong LIN , Yao Zu CHEN
2004, 15(5): 539-542
[Abstract](177) [FullText HTML] [PDF 1710KB](0)
Abstract:
Two novel ent-kauranoids with new sub-skeleton types, gesneroidins G and H were isolated as white powder from the ether extract of the leaves of Isodon gesneroides through normal phase column chromatography. Their structures were elucidated as 3β,6α,7β-triacetoxyl-15-hydroxyl-14-oxo-ent-15,16-seco-kaur-11,17-olide and 1α-hydroxyl-3β,6α,7β,11β-tetraacetoxyl-ent-nor-15,17-kaur-8,16-olide on the basis of the spectral evidences including 1D and 2D NMR spectra.
A Novel Isoenzyme of CuZn-superoxide Dismutase from Nicotiana tobacum
Liang Quan SHENG , Shao Min LIU , Hou Rong XIAO , Bing Le XIA , Qing Liang LIU
2004, 15(5): 543-546
[Abstract](240) [FullText HTML] [PDF 1523KB](0)
Abstract:
An isoenzyme of CuZn-superoxide dismutase, denoted as CuZnSODⅢ, has been separated and purified from Nicotiana Tobacum (tobacco) leaves to apparent homogeneity. Its molecular mass is 22976.6Da. It is composed of one subunit, which is consisted of 187 amine acid residues and contains 1 copper and 0.5 zinc atom. The activation energy of the thermal denaturation process has been obtained as about 143.5kJmol-1. Meanwhile, some properties of spectra were investigated.
Method of Spectrophotometric Microanalysis Based on HRP/PET Self-assembly Film
Xiu Ming JIANG , Zhi Chun CHEN , Shao Ming YANG , Han Feng LIN , Xian Fu LIN
2004, 15(5): 547-550
[Abstract](181) [FullText HTML] [PDF 1364KB](0)
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Horseradish peroxidase monolayer was assembled on the surface of PET-CO2- substrate. The reaction kinetics of HRP/PET film and H2O2 in micro reactor was studied using improved spectrophotometer. The relative activity of self-assembly HRP/PET film still remains above 80% after storing for 150 days at 4℃. When applied to determination of H2O2 in sample, the recoveries of H2O2 are 96.5%~101.1%.
Direct Fluorescence Sensing of Metal Ions in Aqueous Solution Using Intramolecular Charge Transfer Emission from Aggregates of Pentaerythrityl Tetra(p-dimethylaminobenzoate)
Zhen Chang WEN , Yun Bao JIANG
2004, 15(5): 551-554
[Abstract](181) [FullText HTML] [PDF 1543KB](0)
Abstract:
Pentaerythrityl tetra(p-dimethylaminobenzoate) (PTDMAB) was synthesized and shown to emit in water-rich aqueous dioxane solutions the intramolecular charge transfer fluorescence that was sensitive to the presence of metal ions.
Studies on the Preparation of Polymer Spherical Symmetry GRIN Sphere and Controlling its Gradient Index Distribution
Ru XIA , Yu Chuan ZHANG , You Min YI , Shi Wei SHI , Qun YANG , Qiang YU
2004, 15(5): 555-558
[Abstract](165) [FullText HTML] [PDF 1099KB](0)
Abstract:
In this paper, a polymer spherical symmetry GRIN sphere lens were prepared by the suspension-diffusion-copolymerization(SDC) technique, selecting methyl methacrylate(MMA) as monomer M1 and acrylic 2,2,2-trifluoroethyl ester(3FEA) as M2. The radial distribution of refractive index of the lens was measured by the shearing interference method, which demonstrated that the quadratic refractive-index distribution was formed in the sphere lens, and its Δn=0.019.
A Mesoscopic Self-assembled Ring of a Femtomole Fluorescein Sessile Droplet on Glass Slide Support
Cheng Zhi HUANG , Ying LIU , Yuan Fang LI
2004, 15(5): 559-562
[Abstract](169) [FullText HTML] [PDF 1581KB](0)
Abstract:
Since the solvent evaporation of a droplet on a hydrophobically pretreated glass slide, femtomole amount of fluorescent materials is carried by the evaporation and results in outward capillary flow to the perimeter of the droplet spot where the solute deposits, and forms a fluorescent ring like deposit (RLD) with submicrometer-scale structures.
Simultaneous Impedance Analysis of Three Parallel Piezoelectric Quartz Crystals for Electrochemical Depletion Layer Effect Study
Hui Yan LIU , Qing Ji XIE
2004, 15(5): 563-566
[Abstract](177) [FullText HTML] [PDF 1584KB](0)
Abstract:
Simultaneous impedance analysis of three one-face sealed resonating piezoelectric quartz crystals (PQCs) in parallel is proposed through admittance measurements of the three PQCs on one impedance analyzer and then non-linear fitting according to the parallel combination of three Butterworth-Van Dyke circuits. Responses of each PQC obtained from the three-PQC mode agreed well with those measured separately in series sucrose aqueous solutions. This novel method has been used for the study of depletion-layer effect during ferri-/ferrocyanide electrochemical reactions.
Rheological Behavior for Mica-filled Polypropylene Composite Melts
Yan Xia CAO , Miao DU , Qiang ZHENG
2004, 15(5): 567-570
[Abstract](170) [FullText HTML] [PDF 1316KB](0)
Abstract:
The study on rheological properties of a series of mica-filled polypropylene (PP) composites was carried out. The influence of surface-treatment of mica particles on dynamic rheological behavior of the composites were dealt with. The viscosity (η) and dynamic modulus (G') of the composite melts were higher than those of PP matrix, especially those for systems treated with silane, which was attributed to the interfacial adhesion enhancement. However, surface-treatment of mica by titanate resulted in lower η and G', as compared with the treatment by silane. The reason for this is believed to be the formation of the mono-molecular layer on the mica surface.
Synthesis of Micron-size Functional Polystyrene Fluorescent Micro-spheres and their Adsorbability to Human Serum Albumin
Di Qiang WANG , He LI , Jie HU , Xian Feng LIAO , Bai Ling LIU
2004, 15(5): 571-574
[Abstract](190) [FullText HTML] [PDF 1103KB](2)
Abstract:
Polystyrene microspheres with sulfo-or aldehyde-surface were synthesized through dispersion polymerization. Functional polystyrene fluorescent microspheres were prepared by the way of adding 2, 5-diphenyloxazole (PPO) into the reaction system directly and dying the blank microspheres in the ethanol solution of PPO. The influence of preparing matters on the encapsulating rate of PPO, and the influence of functional groups on the adsorbability to human serum albumin (HSA) were investigated.
Effect of Fluorination on Aggregate Structure of Perylene Diimide
Min Min SHI , Hong Zheng CHEN , Jing Zhi SUN , Jian YE , Mang WANG
2004, 15(5): 575-578
[Abstract](166) [FullText HTML] [PDF 1378KB](0)
Abstract:
The effect of fluorination on the aggregate structure of a novel fluorinated perylene diimide, N, N'-diperfluorophenyl-3, 4, 9, 10-perylenetetracarboxylic diimide 1, was investigated by UV-Vis absorptions and the conformation simulations from AM1 semi-empirical quantum mechanics modeling. The results showed that in the solid film 1 molecules stacked with the perfluorinated phenyl groups straightly over or below the perylene cores of the adjacent 1 molecules.
Aggregation Properties of an Amphiphilic Methanofullerene Derivative in THF-H2O Solvent Mixtures
Guan Wu WANG , Li Juan JIAO , Er Hong HAO , Yong Ming LU , You Jun YANG
2004, 15(5): 579-582
[Abstract](162) [FullText HTML] [PDF 1444KB](0)
Abstract:
Amphiphilic methanofullerene 1 exhibits strong tendency to form aggregates in THF-H2O solvent mixtures. Two different aggregation processes induced by either varying the solvent composition or upon standing have been found. Concentration has great influence on the aggregation process. Paralleling to the UV-Vis changes, an unusual solvatochromism has been observed in these two different processes.
Rate Constants for the Reactions of NO3· and SO4·- Radicals with Oxalic Acid and Oxalate Anions in Aqueous Solution
Xi Kun YANG , Jia Qiang WANG , Tie Dang WANG
2004, 15(5): 583-586
[Abstract](116) [FullText HTML] [PDF 1295KB](0)
Abstract:
Rate constants for the reactions of NO3· and SO4·-radicals with oxalic acid and oxalate anions in aqueous solution have been measured using pulse radiolysis and laser flash photolysis.
Mechanochemical Reaction of Aromatic Ketones and Aldehydes in the Presence of Zn-ZnCl2
Guan Wu WANG , Lu LIU
2004, 15(5): 587-590
[Abstract](168) [FullText HTML] [PDF 1417KB](0)
Abstract:
The solvent-free reactions of aromatic ketones and aldehydes in the presence of Zn-ZnCl2 were performed with the aid of high-speed vibration mill, Retsch MM200 mixer mill and Retsch RM100 mortar grinder to give pinacol coupling and reduction products in varying yields.
Dehydroaromatization of Methane with a Small Amount of Ethane for Higher Yield of Benzene
Wei CHU , Xiao Yan DAI , Xue Dong LI , Wen Wei JIANG
2004, 15(5): 591-593
[Abstract](235) [FullText HTML] [PDF 959KB](0)
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The dehydroaromatization of methane was investigated with addition of a few ethane. A high benzene yield was achieved at a higher space velocity. The addition of CO2 could improve the stability.
Regiospecific Addition of Uracil to Acrylates Catalyzed by Alkaline Protease from Bacillus subtilis
Ying CAI , Jian Yi WU , Na WANG , Xiao Feng SUN , Xian Fu LIN
2004, 15(5): 594-596
[Abstract](244) [FullText HTML] [PDF 1034KB](0)
Abstract:
Michael addition reactions of uracil to acrylates were catalyzed by an alkaline protease from Bacillus subtilis in dimethyl sulfoxide at 55℃ for 72 h. The adducts were determined by TLC, IR and 1H NMR.
Preparation and Characterization of Super-paramagnetic Nano-beads for DNA Isolation
Xin XIE , Xu ZHANG , Bing Bin YU , Wei Yang FEI
2004, 15(5): 597-600
[Abstract](178) [FullText HTML] [PDF 1612KB](0)
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Unique coupling reagent, bis-(2-hydroxyethyl methacrylate) phosphate was used to prepare coated and functionalized superparamagnetic nanobeads, leading to a simple, effective method for coating the nanobeads. With this method, the thickness of the coating layer and the functional group contents on the nano-beads could be controlled by changing the quantity of the coated monomers. The nanobeads were characterized by means of transmission electron microscopy (TEM) and Fourier transformation infrared spectroscopy (FTIR). The carboxyl-modified magnetic nano-beads were employed to streamline the protocol of isolation of genomic DNA from the human whole blood.
Synthesis of Silica-anchored Sensitizer and its Application in the Preparation of Previtamin D3 from Tachysterol
Chang Jiang YOU , Rong XIE , Yun Yan GAO , Yong Bin HAN , Guo Qiang YANG , Yi LI
2004, 15(5): 601-604
[Abstract](162) [FullText HTML] [PDF 1479KB](1)
Abstract:
A silica gel-anchored photosensitizer was synthesized with anthracene as sensitizer moiety. The photoisomerization of tachysterol to previtamin D3 was carried out with this heterogeneous photosensitizer in ethanol. The experiment results demonstrate that this solid phase photosensitizer is efficient for the photoisomerization and can be simply separated from the reaction mixture by filtration.
The Effects of CO2 Addition on the Partial Oxidation of Heptane for Hydrogen Generation
Ran RAN , Guo Xing XIONG , Shi Shan SHENG , Wei Shen YANG
2004, 15(5): 605-608
[Abstract](177) [FullText HTML] [PDF 1502KB](0)
Abstract:
The effects of CO2 on the partial oxidation of heptane for hydrogen generation have been studied. Based on the experimental results and thermodynamic equilibrium calculations, the validity of CO2 addition to weaken the hot spots, and the feasibility of the autothermal operation are discussed.
Preparation of Composite Charge-mosaic Hollow Fiber Membrane by Interfacial Polymerization
Hao Qin ZHANG , Jin Dun LIU
2004, 15(5): 609-610
[Abstract](185) [FullText HTML] [PDF 754KB](0)
Abstract:
The preparation of composite charge-mosaic membrane included spinning of hollow fiber as the supporting membrane, preparing a selective layer on the inside surface of the fiber by interfacial polymerization. The charge-mosaic membranes show a high salt permeability while retaining sucrose. The charge-mosaic membrane can be effectively used to separate multivalent salts with organic matter of molecular weight great than 300 g/mol in industry.
Preparation and Catalytic Property of MoOx with Meso-porosity
Xin Ping WANG , Ying Jun WANG , Song Hai CHAI , Tian Xi CAI
2004, 15(5): 611-614
[Abstract](184) [FullText HTML] [PDF 1402KB](0)
Abstract:
A partially reduced molybdenum oxide (MoOx) with meso-porosity was prepared for the first time and its catalytic performance in n-heptane isomerization carried out in a fixed bed flow reactor has been studied. And the evolvement of MoOx formation has been characterized by X-ray diffraction and catalytic performance in n-heptane isomerization. The MoOx catalyst obtained from H2 reduction for 12 h, possessing a maximum pore volume at diameter ca. 4.1 nm, exhibited high activity in n-heptane isomerization. The composition of this catalyst is of the predominant MoOx phases, MoO2 phase and trace amount of metal Mo phase.
Preparation and Characterization of Single Crystals of MAPO-43 Molecular Sieve
Jian Jun LI , Guo Dong LI , Chun Yu XI , Jie Sheng CHEN
2004, 15(5): 615-618
[Abstract](170) [FullText HTML] [PDF 1047KB](1)
Abstract:
Large single crystals of MAPO-43 molecular sieve have been synthesized hydrothermally using dimethylamine as the template. The typical molar composition of the starting mixture was 1.0P2O5:0.54Al2O3:0.8MgO:8.5CH3NHCH3:0.68HF:180H2O. The sample was characterized by XRD, TGA, DTA and IR.
Composite Electrode SnO2/TiO2 for Dye-Sensitized Solar Cells
Jiang Bin XIA , Fu You LI , Shu Ming YANG , Chun Hui HUANG
2004, 15(5): 619-622
[Abstract](174) [FullText HTML] [PDF 1268KB](2)
Abstract:
Composite nanoporous electrode SnO2/TiO2 was fabricated for the dye sensitized solar cell (DSSC) with N3 (Cis-Ru). After introducing of TiO2, the open-circuit photovoltage (Voc) was higher than that of the pure SnO2 electrode, while short-circuit photocurrent (Isc) was varied with the ratio of the TiO2. Appropriate content of the TiO2 can be beneficial to the efficiency of the solar cell, and it gives negative impact on the composite electrode when the content of TiO2 is higher.
Molybdenum Disulfide Sheathed Carbon Nanotubes
Xu Chun SONG , Zhu De XU , Yi Fan ZHENG , Gui HAN , Bo LIU , Wei Xiang CHEN
2004, 15(5): 623-626
[Abstract](160) [FullText HTML] [PDF 1557KB](0)
Abstract:
Single and double layered MoS2-coated multiwalled carbon nanotubes (MWCNs) were successfully prepared by pyrolyzing (NH4)2MoS4-coated multiwalled carbon nanotubes in an H2 atmosphere at 900℃. MoS2-coated MWCNs would be expected to have different tribological and mechanical properties compared to MoS2, so it may have potential applications in many fields.
Thermodynamic and Kinetic Studies on the SiH+XH3 (X=N, P) Reactions
Wei Jiang SI , Shu Ping ZHUO , Guan Zhi JU
2004, 15(5): 627-630
[Abstract](172) [FullText HTML] [PDF 1599KB](0)
Abstract:
Based on the quantum chemical study of the silylidyne insertion reaction with NH3 or PH3, the general statistical thermodynamics and Eyring transition state theory with Wigner correction are used to compute the changes of thermodynamic functions, equilibrium constants, A factors and rate constants of the two reactions in the temperature range 200-2000K. The results show that both of these reactions are thermodynamically dominant at low temperatures and kinetically favored at higher temperatures. The comparison between these two reactions shows that the SiH reaction with NH3 is more exothermic than SiH with PH3, while the rate constant of SiH reaction with NH3 is lower than that of SiH with PH3 at the same temperature.
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