1995 Volume 6 Issue 6

SYNTHESIS OF 4-S-(4",5"-DIARYL-1",2",4"-TRIAZOLE-3"-YL)-4-DEOXY-4'-DEMETHYL-EPIPODOPHYLLOTOXIN ANALOGUES
Fang Min LIU , Kuan Ke LU , Yao Zu CHEN
1995, 6(6): 455-456
[Abstract](154) [FullText HTML] [PDF 66KB](0)
Abstract:
Seven title compounds were synthesized by condensation of 4'-demethylepipodophyllotoxin with 4.5-diaryl-3-mercapto-1.2.4-triazoles in the presence of CF3COOH (TFA).
BIOTRANSFORMATION OF α-DIKETONES-SYNTHESIS OF OPTICALLY ACTIVE α-KETOLS
Jian Xin Gu , Zu Yi Li , Guo Qiang Lin
1995, 6(6): 457-458
[Abstract](161) [FullText HTML] [PDF 75KB](0)
Abstract:
Asymmetric reduction of some α-diketones such as 1-phenyl-1, 2-propanedione and substituted benzils with fungus Geotrichum sp.G38 afforded corresponding optically active α-ketols in excellent chemical and optical yields.
SYNTHESIS OF 5-SUBSTITUTED-2-CHLORO-6-METHYL-4, 7-DIOXOBENZOTHIAZOLE DERIVATIVES
Cui Hua LIU , Bin LU , Jing Ling ZHANG
1995, 6(6): 459-462
[Abstract](160) [FullText HTML] [PDF 174KB](0)
Abstract:
A series of 5-substituted-2-chloro-6-methyl-4, 7-dioxobenzothiazole derivatives hare been synthesized by interaction of 2-chloro-6-methyl-4, 7-dioxobenzothiazole with the appropriate alkylamine and alkyl mercaptan.Their structures are identified by UV, IR, 1H-NMR and MS spectrum analysis.
SOLID PHASE SYNTHESIS AND CD SPECTRUMSTUDY OF "ZINC-FINGER" PEPTIDE RELATED TO CAULIMOVIRUS
Hong JI , Ruo Heng , ZHANG Met , Cheng SHAO
1995, 6(6): 463-464
[Abstract](162) [FullText HTML] [PDF 89KB](0)
Abstract:
Caulimovirus contains a highly conserved, low molecular weight protein which has a zinc finger-like motif CysX2CysX4HisX4Cys in common with the animal retroviruses.The zinc finger-like peptide of caulimovirus (17 residues) was synthesized by solid phase method for structural study.Both standard HF treatment and "low-high HF" treatment were used to cleave the peptide from the resin.The peptide cleaved with "low-high" HF had higher purity and yield than that with standard HF cleavage.Circular dichroic spectroscopy indicates that the peptide exhibits a random coil conformation in the absence of zinc but appears to form an ordered structure in the presence of zinc.
DESIGN AND SYNTHESIS OF ANALOGS OF THE SCHISTOSOMA MANSONI P28 ANTIGENIC PEPTIDE P141
Jia Xi XU , Zhi Hui QIN , Jun Y. ANG , Meng Shen CAI
1995, 6(6): 465-466
[Abstract](163) [FullText HTML] [PDF 136KB](0)
Abstract:
Four analogs of the Schistosoma mansoni P28 antigenic peptide P141 were designed according to the similarity in the structure of the amino acid residues and Chou-Fasman's secondary structurally conformational parameters Pα, Pβ and Pt values, also according to the hydrophilicity of the amino acid residues.They were syntliesized by using Merrifield solid phase peptide synthesis method.ELISA experiments showed their antigenicity.
MICROWAVE IRRADIATED DRY WITTIG REACTION
Cai Ding XU , Guo Ying CHEN , Xian HUANG
1995, 6(6): 467-468
[Abstract](160) [FullText HTML] [PDF 76KB](0)
Abstract:
The dry Wittig reaction of stable ylides with aldehydes were performed within several minutes under microwave irradiation.Remarkable rate enhancements and dramatic reductions of reaction times have been observed.
EFFECT OF SOLVENT POLARITY ON THE RATES AND PRODUCT RATIOS OF MICROWAVE INDUCED DIELS-ALDERREACTION
Rong Shun ZHU , Rin Jie HONG , Shu Shan DAI
1995, 6(6): 469-472
[Abstract](155) [FullText HTML] [PDF 130KB](0)
Abstract:
The rates and yields of two Diels-Alder reactions, employing a series of different solvents as the energy-transfer medium under microwave irradiation (frequency, 2450 MHZ) and conventional refluxing at ambient pressure, have been compared The more polar the solvent used, the more increasing in yield was got by microwave irradiation.
UVARIGRANIN:A NEW ACETOGENIN FROM UVARIA GRANDIFLORA ROXB
Xi Ping PAN , De Quan YU
1995, 6(6): 473-476
[Abstract](162) [FullText HTML] [PDF 150KB](1)
Abstract:
A new Annonaceous acetogenin, named uvarigranin(Ⅰ), was isolated from the ethanol extract of the roots of Uvaria grandiflora Roxb, together with the known isodesacetyluvaricin (Ⅱ).Their plane structures and relative configurations were established on the basis of NMR and MS spectroscopic methods.Compound I belongs to a mono-t trahydrofuran (THF) type acetogenin with an unusual acetoxy group at the adjacent carbon on the THF ring.
EURYCARPIN A, A NEW ISOFLAVONE FROM GLYCYRRHIZA EURYCARPA
Yu Mei ZHANG , Xu Dong XU , Bi Huang HU , Qin LIU , Cui Ying HOU , Yong Long LIU , Jun Shan YANG
1995, 6(6): 477-478
[Abstract](165) [FullText HTML] [PDF 77KB](0)
Abstract:
A new isoflavone designated as eurycarpin A (Ⅰ)has been isolated from the root of Glycyrrhiza eurycarpa P.C.Li.Based on spectroscopic data, its structure was established as 7, 2', 4'-trihydroxy-3'(3, 3-dimethylallyl) isoflavone.
NOVEL TAXANES FROM TAXUS YUNNANENSIS
Hong Jie ZHANG , Han Dong SU , Yoshio TAKEDA
1995, 6(6): 479-482
[Abstract](167) [FullText HTML] [PDF 185KB](0)
Abstract:
Two new taxane diterpenoids from Taxus yunnanensis were elucidated by spectroscopic techniques, one of which was identified as a unique taxane with 2, 20-oxo group.
FOUR NEW TAXANES FROM THE ROOTS OF TAXUS YUNNANENSIS
Hong Jie ZHANG , Han Dong SUN , Yoshio TAKEDA
1995, 6(6): 483-486
[Abstract](166) [FullText HTML] [PDF 216KB](0)
Abstract:
Four new taxanes were isolated from the roots of Taxus yunnanensis.Among them, two were determined to contain isobutyrate group and propionyloxy group on C-14 respectively, and one was determined as the least oxygenated taxane.The structures were elucidated by spectroscopic means.
QUANTUM CHEMICAL STUDY ON THE THERMOLYSES OF 1,5-CYCLOOCTADIENE AND 4-VINYLCYCLOHEXENE
San Guo , HONG Shen WANG
1995, 6(6): 487-490
[Abstract](162) [FullText HTML] [PDF 89KB](0)
Abstract:
MINDO/3 method has been used to study the thermolyses of 1, 5-cyclooctadiene and 4-vinylcyclohexene.The results obtained show that the activation energies of the reta-determining steps are 197.936 and 225.534 kJ.mol-1, respectively.
A NEW AB INITIO CALCULATION METHOD OF INNER-SPHERE REORGANIZATION ENERGY
Yu Xiang BU , Xin Yu SONG , Yu Hua ZHANG
1995, 6(6): 491-494
[Abstract](160) [FullText HTML] [PDF 173KB](0)
Abstract:
On the basis of the improved self-exchange model of reorganization phenomenon and accurate potential functions from ab initio calculation at HFSCF 6-31G and DZP levels, a new calculation method was presented for the inner-sphere reorganization energy, values for diatomic molecular redox couples in gas phase electron transfer process have been calculated.Results agree well with the experimental data, and the effectiveness and importance of this method have been demonstrated for calculation of innersphere reorganization energy in gas phase electron transfer process.
A NEW RAPID FLUOROMETRIC METHOD FOR DETERMINATION OF SULFONAMIDES
Huai Na LI , Yun Xiang CI
1995, 6(6): 495-496
[Abstract](156) [FullText HTML] [PDF 111KB](0)
Abstract:
A new fluorometric method for the determination of sulfonamides is described, based on the formation of a fluorescent inclusion complex of carbonic anhydrase (CA) with dansylamide (DNSA).The fluorescence maximum emission of the complex is at 460nm with excitation at 280nm.Dissociation constants were determined for the CA-sulfonamide complexes.Limits of detection for DNSA, sulfanilamide(SAN) and ptoluenesulfonamide (PTSN) were 0.84, 19.5 and 6.1ng/ml, respectively.The recommended method was applied to the determination of sulfonamides in cow milk at ng/ml level.
GC/MS CONFIRMATORY METHOD OF BENZTHIAZIDE IN HUMAN URINE
Yang QIN , Chang Jiu ZHANG , You Xuan XU , Shao Tang ZHU
1995, 6(6): 497-500
[Abstract](165) [FullText HTML] [PDF 128KB](2)
Abstract:
A GC-MS method for the confirmation of benzthiazide is reported for the first time.This method is based on the main decomposed product of the methylated.derivative and provides a reliable detection of this drug.The detection limit of the method is 1.0ng with selected ion monitoring.
ELECTROCATALYSIS OF NICKEL HEXACYANOFERRATE MODIFIED MICROBAND GOLD ELECTRODE FOR OXIDATION OF REDUCED NICOTINAMIDE ADENINE DINUCLEOTIDE
Chen Xin CAI , Huang-Xian JU , Hong Yuan CHEN
1995, 6(6): 501-504
[Abstract](166) [FullText HTML] [PDF 154KB](0)
Abstract:
A nickel hexacyanoferrate modifled microband gold electrode, which can be prepared by cyclic voltammetry, exhibits excellent electrocatalytic activity for NADH oxidation with an overpotential ca.340mV lower than that at the bare electrode.Quantitative analysis of the electrocatalytic reaction based on rotating disk voltammetry gives a rate constantk of the order of 103 L·mol-1·s-1.
EFFECTS OF GAS FLOW RATE ON CLARK-TYPE OXYGEN GAS SENSOR
Shan Jun LIU , Han Xi SHEN , Ying Hua QIU , He WANG , Jian Xing FENG
1995, 6(6): 505-508
[Abstract](159) [FullText HTML] [PDF 107KB](0)
Abstract:
The flow rate sensitivity of membrane-covered oxygen gas sensor has been tested experimentally.As the oxygen sensor, gas flowmeter, and air pump are arranged in six types of connective modes, the flow rate sensitivity of oxygen sensor is notably different.Preliminary results on the positional flow rate sensitivity of oxygen gas sensor are reported.
MICROVOLTAMMETRIC STUDIES ON VITAMIN B1 ION-SELECTIVE MICROELECTRODE BASED ON A LIQUID/LIQUID INTERFACE
Bo HUANG , Ba Zhang YU , Pei Biao LI , San Fang WU
1995, 6(6): 509-512
[Abstract](161) [FullText HTML] [PDF 130KB](0)
Abstract:
A vitamin B1 (VB1) ion-selective microelectrode based on nitrobenzene and 1, 2-dichloroethane/water interfaces at the tip of a dual-section micropipette was examined by using cyclic voltammetry, asymmetric sweep rate cyclic voltammetry and stripping voltammetry.Trace VB1 could be determined down to 4.6×10-6mol/L in aqueous sample solution, and some transfer data of VB1 were obtained.
THE FUNCTION OF La(Ⅲ) ON "ION-GATE" OF THE GLUTATHIONE MONOLAYER GOLD ELECTRODE
Zi Wei JIANG , Wen Kuan XIN , Xiao Xia GAO
1995, 6(6): 513-516
[Abstract](161) [FullText HTML] [PDF 180KB](0)
Abstract:
The regulative function of La3+on the self-assembled glutathione(GSH) monolayer Au electrode for the ion-gate response was studied in aqueous Fe(CN)6 solution at pH 5.6 and compared with the function of Ca2+.It was found that La3+ has stronger effect than Ca2+.
SiO2-SUPPORTED HRh (DPPE)2 GATALYST
Chang Ping SHAO , Jie Yu WANG , He Fu GUO
1995, 6(6): 517-518
[Abstract](158) [FullText HTML] [PDF 92KB](0)
Abstract:
The catalytic behaviours of SiO2-supported HRh (DPPE)2 catalyst for CO hydrogenation and hydroformylation of propene were reported.
SYNTHESES, CHARACTERIZATION AND CATALYSIS OF (dppe)Rh (μ-CO)2M (CO)3 (M=CR,Mo,W) CARBONYL COMPOUNDS
Chang Ping SHAO , Jie Yu WANG , Xiu Zhi YANG , He Fu Guo
1995, 6(6): 519-520
[Abstract](179) [FullText HTML] [PDF 81KB](0)
Abstract:
The (dppe)Rh (μ-CO)2M (CO)3 (M=Cr, Mo, W) heterobinuclear metal carbonyl compounds were synthesized and characterized by IR and 1NMR.Their catalytic activities for CO hydrogenation were determined.
HYDROGENATION OF CARBON MONOXIDE TO LIGHT OLEFINS ON IRON CATALYSTS PROMOTED WITH ZIRCONIA
Kai Done CHEN , Yi Nine FAN , Qi Jie YAN
1995, 6(6): 521-522
[Abstract](156) [FullText HTML] [PDF 78KB](0)
Abstract:
Fe2O3/ZrO2 catalysts were used for CO hydrogenation.For 7%wt Fe2O3/ZrO2, the F-T products distribution significantly deviated from the Schulz-Flory rule and selectivity to light olefins was enhanced.
EFFECTS OF SUBSTITUENTS IN ETHENYL ANILINE DERIVATIVE WITH DONOR AND ACCEPTOR GROUP ON PHOTOVOLTAIC BEHAVIOR
Bao Hui WANG , De Jun WANG , Shu Qing MA , Yi Cul , Dong ZHANG , Bao Wen ZHANG , Tie Jin LI
1995, 6(6): 523-526
[Abstract](159) [FullText HTML] [PDF 145KB](0)
Abstract:
We report here the photovoltaic behavior of a series of substituted ethenyl aniline derivatives containing donor and acceptor groups.This work indicates that the photovoltaic response is closely correlated with the substituents.The molecular structure/photovoltaic response relationship is presented and discussed in terms of the charge separation in an intramolecular charge transfer compound.
INFLUENCE OF DOPING COMPONENT ON THE SOL-GEL PROCESS
Yue Hua CHEN , Bao Fang JIN , Ping WANG , Guo Lin GUO
1995, 6(6): 527-530
[Abstract](157) [FullText HTML] [PDF 150KB](0)
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29Si and 7Li NMR have been used to study the sol-gel process.It has been found that the doping components (such as TlNO3, LiNO2, and Cd(NO3)2) could promote the hydrolysis and condensation reactions and their ratio, thus they could influence the gelation time.The lithium species has been demonstrated to remain as free hydration ions during the whole sol-gel process and not to participate in forming the inorganic network.
THE INTERACTION OF Co(Ⅱ), Ni(Ⅱ), Cu(Ⅱ) AND Zn(Ⅱ) WITH 6-AMINOPENICILLANIC ACID IN AQUEOUS SOLUTION
Xiang Dong ZHANG , Wei GUAN , Qi Tao LIU , Pin YANG
1995, 6(6): 531-532
[Abstract](176) [FullText HTML] [PDF 93KB](0)
Abstract:
The complex formation equilibria of M2+ ions (M=Co, Ni, Cu, Zn) with 6-aminopenicillanic acid (6-APA) have been studied through potentiometric titrations.The results show that all of metal ions form 1:1 complexes (M(APA)+, M(APA) (OH)) with 6-APA in solution.Formation constants of the complexes were determined at 40℃ in aqueous solution having a fixed ionic strength (0.1M NaClO4) and correlated with the second-order rate constants for metal-ion catalysed hydrolysis of penicillin.
FERROMAGNETICALLY COUPLED Gd (Ⅲ)Cu (Ⅱ)Gd (Ⅲ)TRINUCLEAR COMPLEXES
Ming Ming MIAO , Dai Zheng LIAO , Zone Hui JIANG , Geng Lin WANG
1995, 6(6): 533-536
[Abstract](172) [FullText HTML] [PDF 179KB](0)
Abstract:
Three new heterotrinuclear complexes have been synthesized and characterized, namely {[Gd(L)2]2 [Cu (pbaOH)]} (ClO4)4, where pbaOH denotes 2-hydroxy-1, 3-propylenebis(oxamato), L stands for 1, 10-phenanthroline (phen), 5-nitro-1, 10-phenan-throline (NO2-phen) or 2, 2'-bipyridyl (bpy).The temperature dependence of the magnetic susceptibility of {[Gd(phen)2 (ClO4)2]2 [Cu (pbaOH)]} (ClO4)2 has been studied in the 4-300K range, giving the exchange integral J=6.69 cm-1.This indicates a weak ferromagnetic interaction between the copper(Ⅱ) and gadolinium (Ⅲ) ions.
FORMYLFERROCENE 5-NORBORNENE-2-CARBOXYLICHYDRAZONE AND ITS TRANSITION METAL(I) COMPLEXES
Qiug Bao SONG , Yong Xiang MA , Xiao Li WU , Yong Min LIANG , Guo Sheng HUANG
1995, 6(6): 537-538
[Abstract](153) [FullText HTML] [PDF 82KB](0)
Abstract:
A new ligand, formylferrocene 5-norbornene-2-carboxylic hydrazonc (HL), and its transition metal (Co2+, Ni2+ and Hg2+) complexes have been synthesized and characterized by elemental analyses, i.r.and 1Hn.m.r.spectra.The single crystal of nickel complex has been obtained and determined by X-ray diffraction method.
THE ELECTRONIC STRUCTURES OF Cp2ZrR2 (R:-H,-CO,-OCH)AND [Zr(CO)6]2-
Wen LI , Ye LIU , Yuan Qi YIN
1995, 6(6): 539-542
[Abstract](158) [FullText HTML] [PDF 185KB](0)
Abstract:
In this letter the calculated results for the title molecules and ion by DV-Xα method are given.The results show that the insertion of CO into Zr-H bond takes place by forming a σ dative bond, and CO into Zr-C bond by forming a feedback π bond, but that of CO into Zr-O bond easily gives rise to the break of the structure.Also, the Cσ atom of Cp2Zr(OCH)2 can not be hydrogenated except for the broken O-C bond.Perhaps these are the basis of ZrO2 catalysis producing light olefin.
PREFERENTIAL SEPARATION OF ALCOHOL FROM AQUEOUS SOLUTION THROUGH HYDROPHILIC MEMBRANES-POLY(ETHYLENEOXIDE) (PEO)/CHITOSAN (CS) BLEND MEMBRANE
Xin Ping WANG , Fu Yao ZHANG , Zhi Quan SHEN , Yi Feng ZHAN , Rong Xuan LIN
1995, 6(6): 543-544
[Abstract](158) [FullText HTML] [PDF 73KB](0)
Abstract:
The pervaporation behaviours of aqueous ethanol mixtures through the poly (ethylene oxide) (PEO)/chitosan (CS) blend membrane have been investigated.The results show that both CS and PBO/CS membranes preferentially permeate ethanol at lower ethanol concentration in feed, and the selectivity of chitosan membrane toward alcohol can be greatly improved by introducing water-soluble polymer PBO into chitosan.
THE ATOMIC WEIGHT OF DYSPROSIUM
Tsing Lien CHANG , Ding Shun CAO
1995, 6(6): 545-548
[Abstract](158) [FullText HTML] [PDF 158KB](0)
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Isotopic ratio measurement was carried out for dysprosium, using the absolute isotopic ratio of europium of our laboratory standard, R151/153=0.9161(15)on 2σ basis, to calibrate the mass spectrometer, yielding the atomic weight of dysprosium, Ar (Dy)=162.500(2) on 2σ basis.In addition, a summary is given for the three rare earth elements examined in this series of atomic weight determinations.
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