2004 Volume 15 Issue 6

Stereoselective Synthesis of Piperamide Alkaloids by Modified Ramberg-Bäcklund Reaction
Yang LI , Yu ZHANG , Xiao Long WANG , Zhi HUANG , Xiao Ping CAO
2004, 15(6): 631-634
[Abstract](175) [FullText HTML] [PDF 1663KB](2)
Abstract:
A convenient and rapid approach for the synthesis of piperamide alkaloids 1a~h by the recently developed one-flask Ramberg-Bäcklund reaction was described. The synthesis of 1e was reported for the first time.
Poly(ethylene glycol)-supported Liquid-phase Parallel Synthesis of Di (aryloxyacetyl) thiosemicarbazides
Xi Cun WANG , Jun Ke WANG , Zheng LI
2004, 15(6): 635-638
[Abstract](159) [FullText HTML] [PDF 1507KB](0)
Abstract:
An efficient poly(ethylene glycol) (PEG)-supported liquid-phase parallel approach to di(aryloxyacetyl)thiosemicarbazides is described. PEG-bound phenol reacted with chloroacetic acid to afford PEG-bound phenyloxyacetic acid, which was readily converted into corresponding phenyloxyacetyl chloride. Subsequent nucleophilic substitution with ammonium thiocyanate followed by addition of aryloxyacetic acid hydrazides gave PEG-bound di(aryloxyacetyl)thiosemi-carbazides, which were easily cleaved to give the resulting library of 1-aryloxyacetyl-4-(4'-methoxylcarbonylphenyloxyacetyl)thiosemicarbazides in good to high yield and high purity.
Synthesis and Characterization of New UV-curable Liquid Crystalline Diacrylates
Hong Bo LIU , Ming Cai CHEN , Zhi Tang HUANG , Kai XU
2004, 15(6): 639-640
[Abstract](184) [FullText HTML] [PDF 582KB](5)
Abstract:
A series of UV-curable liquid crystalline diacrylates were synthesized by using 4, 4'-(terephthaloyldioxy) dibenzoic acid as a mesogen unit.
Microwave-assisted Palladium Catalyzed Cross-coupling Reaction of sodium Tetraphenylborate with Carboxylic Anhydrides
Jin Xian WANG , Yu Quan ZHANG
2004, 15(6): 641-642
[Abstract](161) [FullText HTML] [PDF 675KB](0)
Abstract:
A rapid and efficient method for synthesis of unsymmetrical ketones under microwave irradiation is reported.
Ambient Ionic Liquids Used in the Reduction of Aldehydes and Ketones
Dan Qian XU , Shu Ping LUO , Bao You LIU , Zhen Yuan XU , Yin Chu SHEN
2004, 15(6): 643-645
[Abstract](163) [FullText HTML] [PDF 1071KB](0)
Abstract:
The sodium borohydride reduction of aldehydes and ketones to corresponding alcohols has been accomplished via the use of ionic liquids. The alcohols are easily obtained with excellent yields and the ionic liquid BMImBF4 could be reused.
A Facile Synthesis of N-Phosphoryl Amino Acids Containing Hydroxy Group
Jian Chen ZHANG , Shu Xia CAO , Xiao Li YANG , Yu Fen ZHAO
2004, 15(6): 646-648
[Abstract](165) [FullText HTML] [PDF 1019KB](1)
Abstract:
three kinds of N-(diisopropyloxyphosphoryl) amino acids containing hydroxyl group were prepared in high yield by using diisopropyl phosphite as the phosphorylating agent, sodium hypochlorite as the chlorinating agent and tetrabutyl ammonium bromide as the phase transfer catalyst in basic aqueous media.
A New Deoxygenation Method for Taxanes Using Hypophosphorous Acid
Jun GU , Meng ZHANG , Da Li YIN , Ji Yu GUO , Xiao Tian LIANG
2004, 15(6): 649-651
[Abstract](171) [FullText HTML] [PDF 1306KB](1)
Abstract:
An efficient and practical radical chain deoxygenation method by phosphorus centered radicals generated from hypophosphorous acid was developed in the synthesis of analogues of paclitaxel.
Construction and Analysis of N-phosphoryl Peptide Libraries
Shu Xia CAO , Jian Chen ZHANG , Ming Yu NIU , Kui LU , Xin Cheng LIAO , Yu Fen ZHAO
2004, 15(6): 652-654
[Abstract](171) [FullText HTML] [PDF 1080KB](0)
Abstract:
N-Phosphoryl peptide libraries were constructed by transformation from homo-oligopeptide libraries, which was synthesized by self-assembly of amino acids with the assistance of phosphorus oxychloride. Electrospray ionization mass spectrometry (ESI-MS) was used to monitor the reaction.
Chiral Salen Manganese Complex Immobilized on SBA-15: A New Heterogenized Enantioselective Catalyst for the Epoxidation of Alkenes
Xin Mei ZHENG , Yan Xing QI , Xiao Ming ZHANG , Ji Shuan SUO
2004, 15(6): 655-658
[Abstract](171) [FullText HTML] [PDF 1436KB](0)
Abstract:
Jacobsen's catalyst was immobilized onto SBA-15 by multi-step grafting, and this heterogenized catalyst exhibited comparable catalytic performance with the corresponding homogeneous counterpart for the epoxidation of alkenes, and the catalyst could be recycled effectively several times.
A New Phytosterone from Passiflora wilsonii
Gan Peng LI , Jing Feng ZHAO , Yong Qiang TU , Xiao Dong YANG , Hong Bin ZHANG , Liang LI
2004, 15(6): 659-660
[Abstract](166) [FullText HTML] [PDF 669KB](0)
Abstract:
A new phytosterone named passionsterone 1 has been isolated from the roots of Passiflora wilsonii, along with the known compound 24R-ethyl-5α-cholestane-3β, 6α-diol 2. The structure of passionsterone 1 was elucidated as 24R-ethyl-5α-cholestane-3β, 6α-diol-23-one by spectroscopic means.
A New Bromophenol from the Brown Alga Leathesia nana
Xiu Li XU , Xiao FAN , Fu Hang SONG , Jie Lu ZHAO , Li Jun HAN , Jian Gong SHI
2004, 15(6): 661-663
[Abstract](169) [FullText HTML] [PDF 1024KB](0)
Abstract:
A novel bromophenol was isolated from ethanolic extract of the brown alga Leathesia nana S.et G. The structure was elucidated as (E)-3-(2, 3-dibromo-4, 5-dihydroxyphenyl)-2-methyl- propenal by spectroscopic methods including IR, HREIMS, 1D and 2D NMR techniques.
A Novel Terpenoid from Lappula anocarpa
Yuan Peng JIN , Yan Ping SHI
2004, 15(6): 664-666
[Abstract](172) [FullText HTML] [PDF 881KB](0)
Abstract:
A novel terpenoid, named lappulanocarpine A 1 was isolated from the alcoholic extract of the whole plant of Lappula anocarpa. Its structure was characterized by 1D-, 2D-NMR and HR-ESIMS.
Studies on the Phenylfluorone-Mo(VI) Complex as Interacting Mode Spectroscopic Probe of Protein in OP Microemulsion Medium
Qin WEI , Dan WU , Bin DU , Qing Yu OU
2004, 15(6): 667-670
[Abstract](161) [FullText HTML] [PDF 1624KB](0)
Abstract:
The application of phenylfluorone (PF)-Mo(VI) complex as a spectroscopic probe is studied. In the presence of OP microemulsion at pH 3.04, PF-Mo(VI) complex combines protein rapidly to form a stable compound and the absorbance at 527 nm is in proportion to the concentration of protein in the range 0~16 μg mL-1 for bovine serum albumin (BSA). OP microemuslion media is introduced into protein determination, it has increased markedly the sensitivity of the system. The molar absorption coefficient was 5.98(106 L mol-1 cm-1 for BSA. The assay, with sensitivity, simplicity and tolerance to many foreign substances, is applied to the determination of protein in samples with satisfactory results. Moreover, the binding number of BSA with the complex, which is determined by molar ratio and slope ratio methods, is in good agreement.
Molecular Spectroscopic Study on the Interaction between Heparin and Neutral Red
Li ZHANG , Na LI , Feng Lin ZHAO , Ke An LI
2004, 15(6): 671-674
[Abstract](162) [FullText HTML] [PDF 1557KB](0)
Abstract:
The interaction between heparin and neutral red was investigated by molecular spectroscopic methods. The change of all spectra suggested that positively charged neutral red had interacted with negatively charged heparin. The study of influence factors indicated that electrostatic force and hydrophobic bond might be involved in the interaction. The total binding number per disaccharide unit and intrinsic binding constant were obtained using Scatchard model.
Using the Chiral Organophosphorus Derivatizing Agents for Determination of the Enantiomeric Composition of Chiral Carboxylic Acids by 31PNMR Spectroscopy
Chao CHE , Zhong Ning ZHANG , Gui Lan HUANG , Xin Xing WANG , Zhao Hai QIN
2004, 15(6): 675-678
[Abstract](159) [FullText HTML] [PDF 1473KB](0)
Abstract:
The use of chiral organophosphorus derivatizing agents prepared in situ from chiral tartrate or chiral diamine for the 31PNMR determination of the enantiomeric composition of chiral carboxylic acids is described. The method is accurate, reliable and convenient.
A High Sensitivity Detection Method of Singlet Oxygen and Superoxide Anion
Min HAO , Da XING , Qun CHEN , Juan WANG
2004, 15(6): 679-682
[Abstract](184) [FullText HTML] [PDF 1289KB](1)
Abstract:
This paper, for the first time, reports a method that can be used as a highly sensitive probe for singlet oxygen (1O2) and superoxide anion (O2-) in vitro or in vivo. FCLA(3, 7-dihydro-6-{4-[2-(N'-(5-fluoresceinyl)thioureido)ethoxy]phenyl}-2-methylimidazo{1, 2-a}pyrazin-3-one sodium salt), a chemiluminescence (CL) analysis reagent, has been reported to sensitively react with 1O2 and O2- to emit photons with a spectral peak of 525nm. In this work, when human serum albumin (HSA) was added into FCLA solution to enhance the CL intensity, approximately 20 times, compared to that without HSA. The enhanced CL had the same 525 nm spectral peak, identical to that without HSA. By gradually reducing the molecular oxygen content in the solution, we find that the auto-oxidation of oxygen molecules dissolved in the solution plays an important role in the CL process. Based on these experimental evidences, we propose a novel and highly sensitive detection method of 1O2 and O2-, which may have a great potential in chemical and medical applications.
Highly Sensitive Chemiluminescence Detection for PDMS/Glass Micro-chip Electrophoresis
Xiang Yi HUANG , Jiao Ning WANG , Lin CHEN , Ji Cun REN
2004, 15(6): 683-686
[Abstract](182) [FullText HTML] [PDF 1413KB](0)
Abstract:
This paper described a highly sensitive chemiluminescence detection system for micro-chip electrophoresis (MCE) based on luminol-hydrogen peroxide reaction catalyzed by the metal ions. The micro-chip was composed of poly(dimethylsiloxane) (PDMS) and glass, and was fabricated by micro-machining technology. The surface of channels was dynamically modified by polydimethylacrylamide (PDMA) in order to eliminate unhomogeneous electroosmotic flow (EOF) of the PDMS/glass chip, adsorption of molecules, and improve hydrophobicity on PDMS surface. The detection modes, reagent mix procedures and reaction conditions were optimized and the detection limit of 5 x 10-11 mol/L for cobalt (II) was achieved by MCE with chemiluminescence detection, which was about four orders of magnitude more sensitive than that reported in the reference.
Microwave Synthesis, Characterization and DNA-binding Properties of a New Cobalt(Ⅱ) Complex with 2, 6-Bis(benzimidazol-2-yl)pyridine
Nian Yuan TAN , Xiao Ming XIAO , Ze Lin LI , Takeko MATSUMURA-INOUE
2004, 15(6): 687-690
[Abstract](163) [FullText HTML] [PDF 1315KB](0)
Abstract:
A new cobalt(Ⅱ) complex with tridentate ligand 2, 6-bis (benzimidazol- 2-yl)pyridine has been synthesized by microwave irradiation method and characterized by elemental analysis, electrochemical and spectral methods. The binding of the complex with calf thymus DNA has also been investigated by absorption and fluorescence spectra.
The Catalysis of Sodium Dodecyl Sulfate/1-Pentanol/Water W/O Microemulsion on the Photoisomerization of trans-Stilbene
Xia GUO , Ling LIN , Rong GUO
2004, 15(6): 691-694
[Abstract](162) [FullText HTML] [PDF 1520KB](0)
Abstract:
The photoisomerization of trans-stilbene was studied in the water in oil (W/O) micro-emulsion formed by SDS (sodium dodecyl sulfate), n-C5H11OH (1-pentanol) and H2O. The experimental results show that after 2-minute UV-irradiation, the yield of cis-stilbene is higher in W/O microemulsion than in homogeneous solvent-n-C5H11OH.
High Activity SnO2/Al2O3 Catalyst for NO Reduction in the Presence of Oxygen
Jun Hua LI , Ji Ming HAO , Li Xin FU , Tian Le ZHU , Zhi Ming LIU , Xiang Yu CUI
2004, 15(6): 695-698
[Abstract](170) [FullText HTML] [PDF 1259KB](0)
Abstract:
The novel sol-gel SnO2/Al2O3 catalysts for selective catalytic reduction NO by propene under lean burn condition were investigated. The results showed that the maximum NO conversion was 82% on the SnO2/Al2O3 (5%Sn) catalyst, and the presence of H2O and SO2 improved the catalytic activity at low temperature. The catalytic activity of NO2 reduction by propene is much higher than that of NO at the entire temperature range, and the maximum NO2 conversion reached nearly 100% around the temperature 425℃.
Kinetics of the Esterification Reaction Catalyzed by Lipase in W/O Microemulsions of Alkyl Polyglucoside
Jin Ling CHAI , Shou Qing WANG , Gan Zuo LI , Qing XU , Yan Hong GAO
2004, 15(6): 699-702
[Abstract](166) [FullText HTML] [PDF 1381KB](0)
Abstract:
A novel kinetic mechanism of esterification reaction of 1-hexanoic acid with 1-butanol, catalyzed by lipase, was studied in water-in-oil microemulsions. The microemulsions were formed by alkyl polyglucoside C10G1.54/1-butanol/cyclohexane/phosphate buffer solution. The result shows that when the ratio of mol concentration of 1-butanol to 1-hexanoic acid is about 3.0, the initial rate V0 get the maximum values. This phenomenon was explained by the modified fishlike phase diagrams.
Formation and Oxidation of Hydrogen Molybdenum Bronze on Platinum Electrode in Sulfuric Acid Solution
Jin LU , Jun Hua DU , Wei Shan Li , Jia Mo FU
2004, 15(6): 703-706
[Abstract](154) [FullText HTML] [PDF 1344KB](0)
Abstract:
Hydrogen molybdenum bronze (HxMoO3) can be electrodeposited on platinum and oxidized in two steps to the hydrogen molybdenum bronze with less amount of hydrogen HyMoO3 (y3 when platinum electrode is cycled from -0.2 to 1.3V (vs. SCE) in 0.05 mol/L Na2MoO4+0.5 mol/L H2SO4 solution. During the formation of HxMoO3, the electrochemical reduction of molybdate existing in the form of polymolydate is reversible and is about a five-electron transfer reaction.
The Effect of Ionic Liquids on the CaCO3 Crystal Growth
Zhi Guo HU , Shi Li SONG , Jian Ji WANG , Lin YANG
2004, 15(6): 707-710
[Abstract](159) [FullText HTML] [PDF 1285KB](1)
Abstract:
In this paper, the effect of ionic liquids on the CaCO3 crystal growth has been studied for the first time. The obtained CaCO3 crystals were charactered by the X-ray diffraction and scanning electron micrographs. The results showed that the control ability of ionic liquids for CaCO3 crystals growth was dependent on the counter anion very much.
A Novel Approach to the Prediction of Transmembrane Proteins
Jian Ding QIU , Ru Ping LIANG , Xiao Yong ZOU , Jin Yuan MO
2004, 15(6): 711-713
[Abstract](174) [FullText HTML] [PDF 1040KB](0)
Abstract:
A novel method based on continuous wavelet transform (CWT) for predicting the number and location of helices in membrane proteins is presented. The PDB code of 1yst is chosen as an example to describe the prediction of transmembrane helices (HTM) by using CWT. The results indicate that CWT is a promising approach for the prediction of HTM.
Preparation of a New Polyoxometalate-based Nanoparticles
Xiao Hong WANG , Feng LI , Jing Fu LIU , M. T. POPE
2004, 15(6): 714-716
[Abstract](157) [FullText HTML] [PDF 1060KB](1)
Abstract:
Polyoxometalates (POMs) α-K8 H6[Si2W18Ti6O77] (Si2W18Ti6) loaded starch nanop-articles have been prepared and structurally characterized by elemental analyses, IR spectra and 29Si spectroscopy. The particle size of Si2W18Ti6/starch was estimated by a Transmission electron microscope (TEM) and a 1000HSA MALVIRN Zetasizer instrument. The result shows that the polyoxometalate retained the parent structure after encapsulated by starch microspheres.
Covalent Functionalization of Carbon Nanotube by Tetrasubtituted Amino Manganese Phthalocyanine
Zheng Long YANG , Hong Zheng CHEN , Lei CAO , Han Yin LI , Mang WANG
2004, 15(6): 717-720
[Abstract](159) [FullText HTML] [PDF 1368KB](0)
Abstract:
The multiwall carbon nanotube (MWCNT) bonded to 2, 9, 16, 23-tetraamino manganese phthalocyanine (TAMnPc) was obtained by covalent functionalization, and its chemical structure was characterized by TEM. The photoconductivity of single-layered photoreceptors, where MWCNT bonded by TAMnPc (MWCNT-b-TAMnPc) served as the charge generation material (CGM), was also studied.
The Preparation of Perovskite Nano Powder by Sol-gel from DTPA and the Mechanism of Thermal Decomposition
Zun Li MO , Hong CHEN , Kun Jie WANG , Zheng Hai SHI , He Jun LI
2004, 15(6): 721-724
[Abstract](167) [FullText HTML] [PDF 1199KB](0)
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Dy0.8Sr0.2FeO3 nano powder, a synthetic oxide, is made by sol-gel method from metal nitrate and diethylenetriaminepentaacetic acid (DTPA), and the processing parameters are optimized. The process of the preparation, thermal decomposition and the property of the powder are studied by TG-DTA, IR, TEM, and XRD. The diameter of the average grain is about 70 nm. This new technique can be used in the preparation and the studying of na'no materials in the complex oxide system.
A Novel Synthesis of Titania-silica Mixed Oxide with Mesoporous Structure
Wei Ping HUANG , Hong LI , Bao Qing LI , Feng GAO , Xiu Chen ZHENG , Shou Min ZHANG , Shi Hua WU
2004, 15(6): 725-728
[Abstract](167) [FullText HTML] [PDF 1562KB](0)
Abstract:
Mixture formed from sonicating TiCl4 and Si(OEt)4 in the absence of water is used as precursor and hydrolyzed by using a long-chain organic ammonium bromide as a structure-directing agent. The product, titania-silica, is of mesoporous structure and characterized with SEM, FT-IR, BET, XRD and so on.
Preparation and Characterization of Microencapsulated Hexadecane Used for Thermal Energy Storage
Guang Long ZOU , Zhi Cheng TAN , Xiao Zheng LAN , Li Xian SUN , Tao ZHANG
2004, 15(6): 729-732
[Abstract](168) [FullText HTML] [PDF 1313KB](0)
Abstract:
Polyurea microcapsules about 2.5μm in diameter containing phase change material for thermal energy storage application were synthesized and characterized by interfacial polycondensation method with toluene-2, 4-diisocyanate and ethylenediamine as monomers in an emulsion system. Hexadecane was used as a phase change material and OP, which is nonionic surfactant, and used as an emulsifier. The chemical structure and thermal behavior of the microcapsules were investigated by FTIR and thermal analysis respectively. The results show encapsulated hexadecane has a good potential as a solar energy storage material.
A Simple Method for the Preparation of ZnO Prickly Spheres
Da Zhi LI , Xin Yu SONG , Si Xiu SUN , Jin Xin GUO
2004, 15(6): 733-736
[Abstract](151) [FullText HTML] [PDF 1319KB](0)
Abstract:
The synthesis of ZnO prickly spheres using precipitation followed by heating treatment was investigated. Zn(OH)2 precursor was prepared by precipitation process using Zn(CH3COO·2·2H2O in mixed 1-propanol-water solvent. Sodium dodecyl sulfate (SDS) as the anionic surfactant was added to control the morphology. The size and structure of ZnO prickly spheres were studied using XRD, TEM and SEM. The results showed that the morphologies and size of the spheres strongly depended on the volume ratio of 1-propanol/water and molar ratio of SDS/Zn2+. ZnO prickly spheres composed of nanorods could be obtained, when the volume ratio of 1-propanol/water=2:3 and the molar ratio of Zn2+/SDS≈450:1.
Large Pore Mesoporous MCM-41 Templated from Cetyltriethylammonium Bromide
Lei LIU , Gao Yong ZHANG , Jin Xiang DONG
2004, 15(6): 737-740
[Abstract](163) [FullText HTML] [PDF 1415KB](0)
Abstract:
Following hydrothermal synthesis process, MCM-41 was synthesized by using cetyltriethylammonium bromide as templating agent. The experimental results showed that MCM-41 with pore diameter in the range of 4-7 nm can be obtained by adjusting nSurf./nSi. It was proved that cetyltriethylammonium bromide is an effective templating agent for increasing pore diameter of molecular sieve MCM-41.
A Mixed Plasticizer for the Preparation of Thermoplastic Starch
Xiao Fei MA , Jiu Gao YU , Jin FENG
2004, 15(6): 741-744
[Abstract](163) [FullText HTML] [PDF 1338KB](1)
Abstract:
In this paper, formamide was firstly used as plasticizer to prepare thermoplastic starch (TPS), which could suppress the retrogradation of TPS by X-ray diffractometry (XRD) and show a good flexibility, but was weaker than conventional glycerol-plasticized TPS (GPTPS). When urea was introduced into plasticizer, both the retrogradation and mechanical properties were ameliorated. The tensile stress, strain and energy break of TPS plasticized by urea (wt. 20%) and formamide (wt.10%), respectively, reached 4.83 MPa, 104.6% and 2.17 N·m (Newton?meter) after it had been stored at relative humidity (RH) 30% for one week.
The Study of Alcoholysis of 1, 2-Thiazetidine-1, 1-dioxide with Quantum Chemical Method
Mao Xia HE , Feng ZHU , Da Cheng FENG , Zheng Ting CAI
2004, 15(6): 745-748
[Abstract](724) [FullText HTML] [PDF 1499KB](0)
Abstract:
The alcoholysis mechanism of 1, 2-thiazetidine-1, 1-dioxide with methanol, in which the relatively stable product is sulfonate ester, has been investigated by quantum chemical method. Our calculations indicate the reaction for alcoholysis of 1, 2-thiazetidine-1, 1-dioxide proceeds via two possible mechanisms:concerted and stepwise. In the stepwise mechanism, two possible reaction pathways can be followed while only one possible reaction pathway can be followed in the concerted mechanism.
Theoretical Study on the Long-lived Complexes for the Na+I2 Collision System
Xiao Min SUN , Da Cheng FENG , Zheng Ting CAI
2004, 15(6): 749-752
[Abstract](168) [FullText HTML] [PDF 1619KB](0)
Abstract:
For the Na+I2 collision system, theoretical study is performed on the QCISD(T) level by using ab initio method. The ab initio potential energy surfaces are got and on them the long-lived complexes are found and optimized. These results verify the crossed molecule beam experimental phenomenon and the detailed geometry structures are given for the first time. The role of the complexes in the reaction path is also described in detail.
Calculations of Hyperpolarizabilities for Para-disubstituted Benzenes with the QSPR
Xian Dong ZENG , Xuan XU , Bing Feng WANG , Bing Can WANG
2004, 15(6): 753-756
[Abstract](172) [FullText HTML] [PDF 1499KB](0)
Abstract:
A quantitative structure-property relationship (QSPR) was made for the prediction of the hyperpolarizabilities(β) of para-disubstituted benzenes with the nonlinear optical properties, and the βcal2 calculated by this model accorded better with the experimental values (βexpt) compared with the βcal1 calculated at the CPHF/6-31G*//HF/STO-3G level of theory, especially when β was big.
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