1999 Volume 10 Issue 3

A Novel Tandem Reaction for the Synthesis of Thieno [2,3-C] Pyrazole
Zhong Wen WANG , Jun REN , Han Song CHEN , Zheng Ming LI
1999, 10(3): 189-190
[Abstract](177) [FullText HTML] [PDF 70KB](1)
Abstract:
A new method was found for the synthesis of pyrazoleacetate esters from pyrazolaldehyde.By a new tandem reaction.in which methyl 4-pyrazoleacetate reacted with carbon disulfide andiodomethane.thieno [2.3-c] pyrazole was synthesized.This was an easy method for the synthesis of this type of heterocyeles.
Synthesis and Structure of 3-Aryl-5-cyano-6-methylthio pyrimidine2,4-diones
Hua Yin LIU , Guang Fu YANG , Hua Zheng YANG
1999, 10(3): 191-192
[Abstract](172) [FullText HTML] [PDF 67KB](0)
Abstract:
The title compounds of 3-aryl-5-cyano-6-methylthiopyrimidine2.4-diones weresynthesized by the reaction of ethy1 2-cyano-3.3'dimethylthioacrylate with arylureas.The compound (Ar=p-CH3OC6H4) was recrystallized in acetone/petroleum in space group P2(1/n) with a=1.1602 (2), b=1.5921(3), c=1.3918 (3)nm.β=94.38 (3)° for Z=8.R=0.054.The X-ray analysis showed that there is H-bond interaction among molecules.
Synthesis of Calix [4] pyrroles:A Class of New Molecular Receptor
Shi Jun SHAO , Xian Da YU , Shu Qin CAO
1999, 10(3): 193-194
[Abstract](169) [FullText HTML] [PDF 75KB](0)
Abstract:
Calix [4] pyrroles.as a class of new molecular receptor in the area of supramolecular chemistry.have displayed interesting anion and neutral substrate binding properties.In this paper.several new calix [4] pyrrole macrocycles were synthesised and characterized.
Synthesis of Two New Chiral Blocks for the Construction of Peptide Nucleic Acid (PNA)
Li Gang ZHANG , Ji Mei MIN , Li He ZHANG
1999, 10(3): 195-198
[Abstract](186) [FullText HTML] [PDF 124KB](0)
Abstract:
Protected (I.) and (D)-lysune wore used respectively as starting materials to synthesize two new types of chiral blocks for the construction of PNA.Nucleobasc was linked to α-NH2 of lysine via -CH2C (O)- spacer in type 1.and -C (O)- was used in type Ⅱ.The corresponding oligomers were constructed in solution.
Synthesis and Structural Determination of (2R,4S,5S)-(+)-Threo-5-(2,2-dichloroacetamido)-4-(4-nitrophenyl)-2-aryl-1,3-dioxanes
Jun LIU , Xian Ming HU , Han Sheng XU
1999, 10(3): 199-200
[Abstract](183) [FullText HTML] [PDF 65KB](0)
Abstract:
(2R,4S,5S)-(+)-threo-5-(2,2-dichloroacetamido)-4-(4-nitrophenyl)-2-aryl-l,3-dioxanes, were synthesized with high diastereoselectivity and good yields.The structures of acetals were determined and the configurations were confirmed by 2D-NMR (NOESY).
Synthesis of the (3R, 9S, 10S)-Diastereoisomer of Panaxytriol,a Potent Antitumor Polyacetylene from Panax ginseng
Wei LU , Guang Rong ZHENG , Jing Shan SHEN , Jun Chao CAI
1999, 10(3): 201-204
[Abstract](171) [FullText HTML] [PDF 121KB](0)
Abstract:
(3R, 9S.lOS)-Heptadec-l-ene-4,6-diyne-3.9.10-triol 2.a diastereoisomer of panaxytriol 1 was synthesized using L-(+)-diethyl tartrate 5 as a chiral template.through the Cadiot-Chodkiczwicz coupling of the terminal acetylene 3 with bromoacetylene 4.
Aliphatic Phosphenium Canon Featuring A P-S Bond
Tian Bac HUANG , Ling Fei LIU , Xuang Long XU , Wen Fang HUANG , Ke WANG
1999, 10(3): 205-206
[Abstract](173) [FullText HTML] [PDF 84KB](0)
Abstract:
The first aliphatic phosphenium cation featuring a P-S bond (dimethylamino) (methylthio) phosphenium cation 1.has been prepared by treatument of the (dimethylamino) (methylthio) chlorophosphines 2 wih the stoichiometri quantity of AlCl3 in CH2Cl2 solution, and characterized by 1H 13C 27Al and 31P NMR spectroscopy.
A Theoretical Study on Nonadiabatic Trapping Models of the Reaction NH+H←→N+H2
Shu Xia YIN , Yan WANG , WenLin FENG
1999, 10(3): 207-208
[Abstract](175) [FullText HTML] [PDF 78KB](0)
Abstract:
The properties of nonadiabatic trapping models of the reaction NH+H -N+H2 are investigated in a collinear model as well as a non-collinear thermal reaction on the basis of the intrinsic reaction coordinate (IRC) information obtained by ab initio calculations at QCISD/631IG** level.Using the unified statistical theory fornonadiabatic trapping models.the thermal rate constants over the temperature range of 2000-3000K are computed which are in excellent agreement with the experiment results.
Formation of Amino Acid Bridged Zinc Bisporphyrinethylenediamine Linear Supramolecular Array:UV-visible and 1H NMR evidence
Hai Yang LIU , Xiao YING , Xi Ming HU , Yun Li GU , Yi LIU , Jin Wang HUANG , Liang Nian JI
1999, 10(3): 209-212
[Abstract](182) [FullText HTML] [PDF 144KB](0)
Abstract:
Coordination behavior of bidentate ligand ethylenediamine with a new chiral zinc bisporphyrin O.O-C2-AA-C2-(TPP)2 Zn2 was investigated by Uv-Vis titration and 1H-NMR spectroscopy.which further evidenced that O.O-C2-AA-C2-(TPP)2Zn2, tends to form linear assembly with ethylenediamine in chloroform.
Detection of Optical Stability of chiral 2-Methylbutyric Acid in Gas Phase with Quadrupole-Quistor-Quadrupole Mass Spectrometer
Yuan Jiang PANI , U.P.SCHLUNEGGERZ
1999, 10(3): 213-214
[Abstract](172) [FullText HTML] [PDF 67KB](0)
Abstract:
Optical stability of chiral 2-methylbutyric acid in gas phase has been detected with Quadrupole-Quistor-Quadrupole tandem mass spectrometer in combination with deuteration.The results show that these compounds are optically unstable in the process of self chemical ionization.
Poly [(chloromethyl) styrene-co-divinylbenzene] Continuous Rod Column of Weak Cation Exchange Chromatography and its Applications in the Separation of Biopolymers
Quan Zhou LUO , Yin Mao WEI , Tong LIU , Gen Hu LEI , Xin Du GENG
1999, 10(3): 215-218
[Abstract](180) [FullText HTML] [PDF 152KB](0)
Abstract:
Macroporous poly [ (chloromethyl) styrene-co-divinylbenzene] continuous rod was prepared by direct polymerization of the monomers in the presence of a porogenic diluent inside an empty chromatographic column.A new "in-situ" technique was used to modify the synthesized polymer rod for a weak canon exchanger and it has been used successfully for the separation of biopolymers.It was found that the back pressure of the continuous rod column was much lower and its surface was proved to be modified well.
The Separation Efficiency of Biopolymers with Short Column in Liquid Chromatography
Tong LIU , Xin Du GENG
1999, 10(3): 219-222
[Abstract](174) [FullText HTML] [PDF 146KB](0)
Abstract:
The separation efficiency of biopolymers with a short column in liquid chromatography has been investigated in this paper.It was found that the column length has slight effect on the resolution of biopolymers under gradient elution.The reasons have been explained by stoichiometric displacement model for retention of solute.The column 1 .0 cm long was also used in the separation and purification of recombinant human granulocyte colony-simulating factor (rhG-CSF).It only took 40 min and the purity by one step was found to be almost 100%.
Synergistic Effect in Mixed Capillary Gas Chromatographic Stationap Phases Containing Heptakis (2,3,6-tri-o-pentyl)-β-cyclodextrin and Dibenzo-18-crown-6
Li Ming YUAN , Ruo Nong FU , Xue Xian CHEN , Shi Hong GUl , Rong Ji DAI
1999, 10(3): 223-226
[Abstract](177) [FullText HTML] [PDF 137KB](0)
Abstract:
Fused-silical capillary columns containing heptakis (2、3、6-tri-o-pentyl)-β-cyclodextrin and dibenzo-18-crown-6 were prepared.By studying the selectivity of mixed stationary phases for some solute pairs.as well as comparing with the heptakis (2、3、6-tri-O-pentyl)-β-cyclodextrin and thedibenzo-18-crown-6 used as individual stationary phase、the synergistic effects were observed.These effects were affected by the column temperature.mixed ratio and linear velocity of carrier gas.
Triethylamine or diethylenetriamine as dynamic modifier for suppressing basic protein adsorption in capillary electrophoresis
Ying Hua QIU , Al Jin HUANG , Yi Liang SUN
1999, 10(3): 227-230
[Abstract](175) [FullText HTML] [PDF 147KB](0)
Abstract:
Either triethylamine or diethylenetriamine can be conveniently used as a dynamic modifier to suppress the adsorption of basic proteins in capillary zone electrophoresis.Sufficiently high column efficiencies (>2×105 plates/m for cytochrome C) were obtained with either of them along with the improvement of the peak shapes and repeatability of migration time.The relationship between the adsorption suppression effect of the modifier and its structure was discussed.
A New Capillary Electrophoresis Apparatus with Piezoelectric Ceramics High Voltage Source and Amperometric Detector
Zuan Guang CHENI , Jin Yuan MO , Xiao Yun YANG , Li Shi WANG , Xue Ting MEIZ , Min Sheng ZHANGI
1999, 10(3): 231-234
[Abstract](177) [FullText HTML] [PDF 111KB](0)
Abstract:
A new capillary electrophoresis apparatus was designed.Piezoelectric ceramics transformer technology was first applied in capillary electrophoresis.a high voltage and stable source was made.Amperometric detector was used in which the working electrode was closely opposite to the end of capillary.The apparatus was characterized in good reproducibility safety and very low cost.
A Novel Method for Studying the interaction of Macromolecule with Small Molecule by Means of Affinity Capillary Electrophoresis
Met FANG , Li SHENG , Hut Wan HAN , Xiao YU , Rut ZHAO , Guo Quan LIU
1999, 10(3): 235-238
[Abstract](167) [FullText HTML] [PDF 105KB](0)
Abstract:
A novel capillary electrophoresis method coupled with on-line microdialysis using an attachable electrode has been developed to study the interaction of macromolecule with small molecule.The binding constants of bovine serum album (BSA) with D.L-tryptophan (Trp), sulfamethoxazole (SMZ) with trypsin and chymotrypsin were determined.These values are 2.3×104L/mol for BSA-L-Trp.1.77×103 L/mol for BSA-D-TrP in PH 7.4, 50 mmol/ L phosphate; 1.4×104 L/mol for SMZ-trypsin and 6.0×103 L/mol for SMZ-chymotrypsin in PH 6.5, 25 mmol/L Tris buffer.The proposed method has merits of speed.low sample consumption and readily available to be performed in desired physiological conditions.
Studies on Different Hydrolysis Procedures for Drugs of Abuse in Hair
Chen MA , Tong Hut ZHOU
1999, 10(3): 239-242
[Abstract](185) [FullText HTML] [PDF 155KB](0)
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Different hydrolysis and extraction procedures have been studied for the determination of drugs of abuse in hair samples.The results showed that acid and enzymatic hydrolysis gave high extraction recoveries for 6-monoacetylmorphine.morphine.codeine and heroin.Enzymatic hydrolysis was more expensive.After alkaline hydrolysis.6-monoacetylmorphine.a unique proof of heroin abuse.could not be detected and after methanolic extraction.the extract was dirty and the obtained chromatogram showed an interfering background.It is concluded that acid hydrolysis is the extraction method of choice.
Spectroscopic Measurements of Physiological Elements in Microdialysis Samples from Rat Brain,Flowering Plum Fruit and Pea
Hui Min MA , Zhi Hua WANG , Yi ZENG , Hut Wan HAN , Guo Quan LIU
1999, 10(3): 243-246
[Abstract](163) [FullText HTML] [PDF 129KB](0)
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The basal levels of magnesium and copper in rat brain and flowering plum fruit dialysates.and the background concentration of calcium in pea dialysates have been determined with sensitive spectroscopic techniques including atomic absorption spectrometry and spectrophotometry based on amino G acid chlorophosphonazo.It is found that the magnesium level in flowering plum fruit dialysates is much lower than that in rat brain dialysates.indicating a considerable composition difference present between a plant dialysate and an animal one.
Indirect Differential Pulse Voltammetric Determination of Aluminum by a Pyrocatechol Violet-Modified Electrode
Shu Ping BI , Gang CHEN
1999, 10(3): 247-250
[Abstract](179) [FullText HTML] [PDF 162KB](0)
Abstract:
A PCV-modified electrode was simply prepared by dip-coating a pyrolytic graphite electrode in a NaAc-HAc buffer solution of PCV.The peak currents of differential pulse voltammograms (DPV) decrease with the addition of Al and the peak potentials remain the same.The decreasing of △ip, is linear with Al concentration in the range of 1×10-8~ 1×10-7 mol/L.The detection limit is 5 ×10-9 mol/L and the relative standard deviation for 4×10-8 mol/L Al is 2.9% (n=8).No serious interference was found.The determination of Al in water samples is reported.
A Novel Biferrocene Trinuclear Complex with Cis-Configuration
Jie Ying WU , Yu Peng TIAN , Fu Xin XIE , Shi Sheng NI
1999, 10(3): 251-254
[Abstract](162) [FullText HTML] [PDF 128KB](0)
Abstract:
A novel biferocene trinuclear complex for Schiff base ligand S-methyt-N-(ferrocenyll-methyl -methylidene) dithiocarbazate (hereafter abbreviated as HL) is described.X-ray diffraction studies established the structure of the palladium complex, PdL2.The geometry of Pd (Ⅱ) in the complex is close to square planar and in novel cis-configuration with two ferrocene moieties on the same side.Degenerate four-wave mixing (DFWM) measurements show that the complex exhibit obvious nonlinear optical response.
Synthesis, Electrochemistry, Fluorescence and ECL of Ru (phen)2 (dcbpy) (PF6)2
Peng WANG , Yi YUAN , Guo Yi ZHU
1999, 10(3): 255-256
[Abstract](177) [FullText HTML] [PDF 73KB](0)
Abstract:
A new ECL-active species.Ru (phen)2 (dcbpy) (PF6)2.has been designed and synthesized.Its structure was confirmed by means of IR.ESI-MS and 2D NMR.Also.its properties of electrochemistry.fluorescence and ECL are reported.which have suggested a good hope of being used in electrochemiluminescent immunoassay and nucleic acid hybridization.
Synthesis, Structure and Non-linear Optical Properties of Manganese Mercury Tetrathiocyanate
Yun Xing YAN , Qi FANG , Duo Rong YUAN , Yu Peng TIAN , Zhi LIU , Xiao MeiWANG , Min Hua JIANG , D.WILLIAMS , A.SIU , Zhi Gang CAI
1999, 10(3): 257-260
[Abstract](172) [FullText HTML] [PDF 133KB](0)
Abstract:
The title copound Manganese Mercury Tetrathiocyanate (MnHg (SCN)4) has been synthesized and its structure has been determined.It belongs to tetragonal system, 4 space group.The cell dimensions are:a=1.1324 (3)nm, c=0.4270 (2) nm.V=0.5475 (3)nm3, Z=2, Dc= 2.959 g/cm3, R=0.028, Rw = 0.037.The structure feature of the crystal is the Hg-S-C N-Mn bridge which leads to the formation of an infinite three dimensional network.Irradiated by a 1064 nm Nd:YAG laser beam.MnHg (SCN)4 shows a 532 nm second harmonic intensity which is 18 times as that of organic nonlinear optical crystal urea, and therefore shows a quite promising application value as a useful nonliear optical material.
Synthesis of Multifunctional Polysiloxanes for Photorefractive Effect
Jun LI , Peng REN , Cat Mao ZHAN , Jin Gut QIN
1999, 10(3): 261-262
[Abstract](178) [FullText HTML] [PDF 80KB](0)
Abstract:
A novel kind of multifunctional polysiloxane containing charge-transporting agent and as electro-optical chromophore has been prepared for photorefractive application.The structural characterization of this kind of polymer is presented by IR spectra and elemental analysis.
Synthesis and Spectroscopic Characteriration of Transition MetalComplexes of Maleionitriledithiolene and 1,10-Phenanthroline
Zheng He PENG , Xiao Ming REN , Chen Jie FANG , Bin Guang ZHANG , Ju Tang SUEN
1999, 10(3): 263-266
[Abstract](165) [FullText HTML] [PDF 152KB](0)
Abstract:
The title complex M (mnt) (phen), M=Fe11, Co11.Ni11, Cu11.Zn11.was respectively synthesized by reaction of disodium maleionitriledithiolate (Na2 (mnt)) with corresponding metal complex M (phen) Cl2.Charge transfer transitions in the absorption and emission spectra have been studed.
Effect of Templates on the Structure and Stability of Ti-TMS
Qing DAI , Nong Yue HE , Xing Li WANG , Xun Wei SHEN , Yan GUO , Chun Wei YUANI
1999, 10(3): 267-268
[Abstract](169) [FullText HTML] [PDF 84KB](0)
Abstract:
Pure Mesoporous TiO2 molecular sieves (Ti-TMS) were synthesized with different templates for the first time and the templates can be successfully removed by refluxing the samples in the EtOH/H2O/KOH solution.The XRD pattem and TEM confirm that the uniformity and stability of Ti-TMS2 synthesized with dodecylamine as template is obviously inferior to that of TiTMS1 prepared with dodecylphosphate and hexadecylphosphate as templates.Furthermore.after the templates were removed.the mesostructure of Ti-TMS1 was preserved to a great degree than that of Ti-TMS2.
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