1993 Volume 4 Issue 10

SYNTHESIS OF CYCLIC PEPTIDES USING BBC REAGENT
Shao Qing CHEN , Jie Cheng XU
1993, 4(10): 847-850
[Abstract](167) [FullText HTML] [PDF 100KB](0)
Abstract:
We report here the synthesis of cyclic peptides using benzotriazolyloxy-bis (pyrrolidino)-carbonium hexafluoro-phosphate (BBC) as a coupling reagent with high yield and speed even in low concentration compared with the other usual coupling reagents.
CHEMICAL CONVERSION OF INOSINE INTO 6-(2-METHYL PHENOXY)-PURLNENUCLEOSIDE DERIVATIVES
Li Ya ZHU , Qi Dong ZHANG , Zi Yun LIN
1993, 4(10): 851-852
[Abstract](156) [FullText HTML] [PDF 75KB](0)
Abstract:
A 6-pyridinium salt (2) was obtalned from 2', 3', 5'-tri-O-acetyhnosine by use of phosphoryl chloride as the condensmg agent. The conversion of salt (2) into 6-(2-methylphenoxy)-purinenucleoside (3) denvatives under mild condition is also described.
STUDY ON Cp2TiCl2/Fe-INITIATED ADDITION OF 2-HALOTETRAFLUOROETHYL IODIDES TO ALKYNES AND ALKENES
Chang Ming HU , Jian CHEN , Yao Ling QIU
1993, 4(10): 853-854
[Abstract](155) [FullText HTML] [PDF 78KB](0)
Abstract:
Initiated by CP2TiCl2/Fe redox system, 2-halotetrafluoroethyl iodides readily reacted with alkynes or alkenes to give 1:1 adducts in good to excellent yields.
SYNTHESIS AND CONFIGURATION OF THE DEGRADATION PRODUCT OF YINGZHAOSU B
Xing Xiang XU , Qiao Sheng HU
1993, 4(10): 855-856
[Abstract](144) [FullText HTML] [PDF 77KB](0)
Abstract:
Synthesis of the degradation product 2 of Yingzhaosu B was accomplished and the configuration was determined.
REGIOSELECTIVE ALLYLATION OF THE TERMINAL EPOXIDES BY ALLYL BROMIDE AND METALLIC ZINC OR TIN
Dao Li DENG , Zhong Hui LU
1993, 4(10): 857-858
[Abstract](151) [FullText HTML] [PDF 65KB](0)
Abstract:
Allylation of terminal epoxides (1) to give the homoallylic alcohols (2) and bishomoallylic alcohols (3) can be carried out successfully by allyl bromide and metallic zinc or tin. The effect of substituents on epoxides was studied.
AN EFFICIENT SYNTHESIS OF DEOXOQINGHAOSU FROM DIHYDROQINGHAOSU
Ya Jing RONG , Bin YE , Chun ZHANG , Yu Lin WU
1993, 4(10): 859-860
[Abstract](151) [FullText HTML] [PDF 72KB](0)
Abstract:
Deoxoqinghaosu, a more active antimalarial compound than qinghaosu, was efficiently synthesized from the readily available dihydroqinghaosu with a new reducing reagent BH3NEt3-Me3SiCl.
SOLVENTLESS CYCLOCONDENSATIONS BETWEEN 1-NAPHTHOL AND BENZILS
Ji Ben MENG , Zhong WEN , Yong Mei WANG , Hong Gen WANG
1993, 4(10): 861-864
[Abstract](152) [FullText HTML] [PDF 130KB](0)
Abstract:
In the absence of organic solvents, the Lewis acid catalyzed cyclocondensation reactions between 1-naphthol and benzils gave 3-aryl-3-aryl' naphtho[1, 2-b]furan-2(3H)-ones (NFs) in good yields (62%~70%) An electrophilic substitution mechanism involving formation of n-EPD/v-EPA complexes and rearrangement of aryl group was proposed.
RESEARCH ON THERMOREACTIONS BETWEEN INDOLE AND 9,10-PHENANTHRAQUINONE
Ji Ben MENG , Zhong WEN , Yong Mei WANG , Hong Gen WANG
1993, 4(10): 865-868
[Abstract](148) [FullText HTML] [PDF 131KB](0)
Abstract:
Solventless reactions between indole and 9, 10-phenanthraquinone (PQ) have been carried out in the presence/absence of zinc chloride. The 1, 2-photoadduct between indole and PQ was identified as a possible intermediate in thermoreactions. An electrophilic substitution mechanism involving formation of n-EPD/v-EPA complex was proposed.
ALLYLATION OF AROMATIC AMINES VIA ALLYLDIALKYLTELLURONIUM SALTS
Cai Ding XU , Shou Mao LU , Xian HUANG
1993, 4(10): 869-870
[Abstract](150) [FullText HTML] [PDF 80KB](0)
Abstract:
Allyldialkyltelluronium bromides were treated with aromatic amines in 1, 2-dichloroethane, readily giving allyl aryl amines in excellent yields. This method provides a convenient one-pot reaction for the synthesis of allylic amines.
SYNTHESIS OF POLYSUBSTITUTED AROMATIC COMPOUNDS:Ⅰ.THE DIELS-ALDER REACTION OF SELENO SUBSTITUTED 3-SULFOLENES WITH DIMETHYL ACETYLENEDICARBOXYLATE
Guang Dian HAN , Guo Feng HUANG
1993, 4(10): 871-872
[Abstract](147) [FullText HTML] [PDF 64KB](0)
Abstract:
The seleno substituted aromatic compounds were prepared via the Diels-Alder reaction of seleno substituted 3-sulfolenes with dimethyl acetylenedicarboxylate followed by DDQ dehydrogenation.
IR STUDIES OF THE SIDE CHAIN ALKYLATION OF TOLUENE WITH METHANOL ON ZEOLITE CATALYSTS
Wen Gui GUO , Guang Yu CAI , Ji Wu ZHANG , Juan LIANG , Guo Quan CHEN
1993, 4(10): 873-876
[Abstract](158) [FullText HTML] [PDF 116KB](0)
Abstract:
Surface species resulting from the decomposition of methanol on Na-、K-、Rb-、Cs-、BCs-、KCs- and KBCs-X zeolite at 420℃, and the relationship between surface species and the side chain alkylation selectivity from toluene with methanol have been studied by infrared and gas chromatographic methods.
REACTION OF 3-ACETYLTROPOLONE WITH 2-HYDROXYBENZALDEHYDES
Dao Lin WANG , Zhong Tian JIN
1993, 4(10): 877-878
[Abstract](145) [FullText HTML] [PDF 69KB](0)
Abstract:
3-Acetyltropolone (1) reacted with 2-hydroxybenzaldehyde (2a), 2-hydroxy-5-methylbenzaldehyde (2b), 5-chloro-2-hydroxybenzaldehyde (2c) and 2-hydroxy-l-naphthaldehyde in presence of ethylformate and perchlor ic acid to give the corresponding pyranylium tropolone perchlorate.
THE AVERAGE AGGREGATE NUMBER OF ELECTROSTATICALLY STABILIZED AGGREGATE (ESAg)
Jin Tao ZHANG , Bo TU , Guo Zhen JI , Xi Kui JIANG , Zhen He TONG
1993, 4(10): 879-882
[Abstract](154) [FullText HTML] [PDF 121KB](0)
Abstract:
The average aggregate number (N) of electrostatically stabilized aggregate (ESAg) composed of oppositely-charged long-chain molecules, i. e., sodium ω-[α-(nathphyl) ethoxyl]undecanoate (FP-) and cetyltrimethyl ammonium chloride (CTAC), in aqueous solution at 25℃ has been measured to be 11 to 16 in the CTAC-concentration range of 11×10-5 M to 30×10-5 M at a fixed FP- concentration of 1.0×10-5 M by the photon counting method.
INTERACTION OF PLASMA-LIQUID IN AN OXYGEN GLOW DISCHARGE Ⅲ.OXIDATION DESULFURIZATION OF ETHYL-THIOETHER
Wan Ying LIU , Wei LU , Zheng Lan LEI , Jin Kun WANG
1993, 4(10): 883-884
[Abstract](154) [FullText HTML] [PDF 70KB](0)
Abstract:
A few factors affecting plasma oxidation desulfurization of ethylthioether were investigated. Under the typical conditions, the conversion and degree of desulfurization of ethyl-thioether can be achieved up to 88% and 79% respectively.
TWO NEW COUMARINS FROM ANGELICA PUBESCENS F.BISERRTA
Jiang Hua LIU , Ying Jie GUO , Sui Xu XU , Xin Sheng YAO
1993, 4(10): 885-886
[Abstract](150) [FullText HTML] [PDF 74KB](0)
Abstract:
Two new coumarins, 4'-hydroxycolumbianetin named angelidiol (A) and 6-[1 (R), 2 (S)-3-trihydroxy-3-methylbutyl]-7-methoxycoumarin named angelitriol (B), were isolated from the EtOAc-soluble fraction of the 80% EtOH extract and structurally eluciated on the basis of spectral analyses.
STUDIES ON THE CHEMICAL CONSTITUENTS OF TAXUS CUSPIDATA
Xiao Jie TONG , Wei Shuo FANG , Jin Yun ZHOU , Cun Heng HE , Wei Ming CHEN , Qi Cheng FANG
1993, 4(10): 887-890
[Abstract](146) [FullText HTML] [PDF 128KB](0)
Abstract:
From the methylene chloride extract of the leaves and stems of Taxus cuspidata Sieb et Zucc twelve taxane diterpenoids have been afforded. The structures of two novel taxane diterpenes, named 10-deacetyltaxinine B (1) and taxacustin (2) were characterized by spectroscopic techniques and X-ray diffraction analysis.
CIMICIFUGAMIDE AND ISOCIMICIFUGAMIDE,TWO NEW CINNAMAMIDE DERIVATIVES ISOLATED FROM CIMICIFUGA DAHURICA
Cong Jun LI , Di Hua CHEN , Pei Gen XIAO
1993, 4(10): 891-892
[Abstract](149) [FullText HTML] [PDF 112KB](0)
Abstract:
Two new cinnamamide derivatives designated as cimicifugamide (1) and isocimicifu-gamide (2), have been isolated from the rhizomes of Cimicifuga dahurica (Turcz. ) Maxim.. Theirs tructures were established based on spectral evidence as N-(3'-methoxy-4'-hydroxyphenethyl)-4-0-β-D-galactopyrano syl-ferulamide (E) and N-(3'-methoxy-4'-hydroxyphenetnyl)-4-0-β-D-galactopyranosyl-isoferulamide (Z) respectively.
A NEW SESQUITERPENE FROM CHRYSANTHEMUM INDICUM
De Quan YU , Feng Zhi XIE
1993, 4(10): 893-894
[Abstract](150) [FullText HTML] [PDF 53KB](0)
Abstract:
A new sesquiterpene with an eudesmane skeleton, named Chrysantherol was isolated from the flowers of Chrysanthemum indicum. Its structure was elucidated as 1 mainly by the analysis of spectral data.
SINAPYL ALCOHOL DERIVATIVES AND OTHER CONSTITUENTS FROM THE ROOTS OF LIGULARIA NELUMBIFOLIA
Yu ZHAO , Zhong Jian JIA , Li YANG , Jin Gang WANG
1993, 4(10): 895-898
[Abstract](146) [FullText HTML] [PDF 136KB](0)
Abstract:
Phytochemical investigation of the roots of Ligularia nelumbifolia afforded three new sinapyl alcohol derivatives together with two other novel constituents. Their structures were elucidated by high field 1D and 2D NMR techniques and chemical transformations.
THE HEI PHOTOELECTRON SPECTROSCOPIC STUDY OF MICROWAVE-DISCHARGED SPECIES OF METHYL IODIDE
Guo Hong WANG , Dian Xun WANG , Wen Xiang YANG , Guang Zhi XU
1993, 4(10): 899-902
[Abstract](157) [FullText HTML] [PDF 101KB](0)
Abstract:
The detection of the microwave-discharged species of methyl iodide by HeI photoelectron spectroscopy (UPS) is reported for the first time. The UPS spectra of I2 and HI molecules clearly appeared in the spectrum of microwave-discharged species of methyl iodide, The mechanism of the change of methyl iodide under microwave discharge was proposed, The result provides the basis for understanding depletion of the ozone shell of the atomsphere by halogenated methane.
AN IMPROVED MODEL FOR COMPUTING SOLUTION DYNAMICS OF NATURAL PRODUCTS WITH 13C NUCLEAR MAGNETIC RELAXATION
Yan Wu YANG , Ang JI , Bing Lin HE , Xin YAN , Xiao Long XU , De Hun WANG , Bao Gong QIAN
1993, 4(10): 903-906
[Abstract](148) [FullText HTML] [PDF 133KB](0)
Abstract:
The fully anisotropic molecular overall tumbling model with methyl conformation jumps internal rotation among three equivalent sites is proposed, the overall tumbling rotation rates and the methyl internal rotation rates of ponicidin are computed with this model from 13C relaxation parameters.
A STUDY OF THE INTERACTION AND FORMATION CONSTANTS OF NAPHTHALENE DERIVATIVES WITH CYCLODEXTRIN BY FLUORESCENCE AND CIRCULAR DICHROISM SPECTRA
You Ming ZHANG , Bao Jian SHEN , Lin Hui TONG , Dao Sen JIN , Lian Xiang ZHANG
1993, 4(10): 907-908
[Abstract](159) [FullText HTML] [PDF 89KB](0)
Abstract:
The molecular recognition of the α, β-CD and 6A, 6C(D)-o, o'-(4, 4'-diphenyloxide-disulfonyl)-β-CD to naphthalene derivatives was studied by fluorescence and circular dichroism spectra. The formation constants of the inclusion complexes were estimated based on the variation of fluorescent intensity and the modified Benesi-Hildebrand equations.
SURFACE ENHANCED RAMAN SCATTERING OF C60 FILMS ON VARIOUS ACTIVE SUBSTRATES
Shi Jie LI , Xiao Pin XU , Zong Pu QI , Wen Zhou LI
1993, 4(10): 909-912
[Abstract](139) [FullText HTML] [PDF 105KB](0)
Abstract:
In this paper, we report the study of surface-enhanced Raman Scattering of C60 films on roughed Ag, Cu and glass surface. The experiment results indicate that the C60 films on Ag substrate possess large enhance effect. An explanation of the enhancement with roughed glass surface is proposed based on waveguide Raman Scattering.
DETERMINATION OF ORGANIC ACIDS IN SOY SAUCE BY HPLC
Zhi Min XIANG , Li ZHANG , Li Jun BI
1993, 4(10): 913-916
[Abstract](152) [FullText HTML] [PDF 123KB](1)
Abstract:
Organic acids in 3 kinds of soy sauces were analyzed by HRLC. Column:C18 μ Bondapak (10μm, 3.9mm i. d. * 30cm;mobile phase:0.5% (NH4)2HPO4 (pH=2.9);flow rate:1.0 ml/m. PT-C18 cartridge was used for the sample preparation. Recoveries of organic acids are between 96-111%.
STUDY ON ANALYTICAL PERFORMANCE OF LOW-POWERED ArMPT-AES
Ying WANG , Xiang Lin YUAN , Han Qi ZHANG , Wen Jun YANG , Qin Han JIN
1993, 4(10): 917-920
[Abstract](156) [FullText HTML] [PDF 151KB](0)
Abstract:
In this paper the analytical performance of the low-powered Ar microwave plasma torch atomic emission spectrometry (MPT-AES) was studied. The experimental results indicate that the analytical performance of low-powered ArMPT-AES is satisfactory.
APPLICATION OF THERMAL ANALYSIS TO THE QUICK DETERMINATION OF THE PROXIMATE ANALYSIS ITEMS AND CALORIC VALUE FOR COAL
Zhen Ku GUO , Lan Xiang MENG , Xin Yu REN , Ya Zhong ZHANG
1993, 4(10): 921-924
[Abstract](140) [FullText HTML] [PDF 139KB](0)
Abstract:
A research on the application of a TG-DTA (thermal gravimetry differential thermal analysis) to the quick determination of moisture, organic volatile fixed carbon, ash and caloric value for coal is described.
A STUDY ON THE ADSORPTIVE VOLTAMMETRIC BEHAVIOUR OF SALICYL-FLUORONE
Xiao Li ZHANG , Li Zeng WANG , Rong Li CHEN
1993, 4(10): 925-928
[Abstract](155) [FullText HTML] [PDF 125KB](0)
Abstract:
In the 0.3mol/L NH4Cl supporting electrolyte, salicyl-fluorone exhibits a sensitive adsorptive wave by using linear scanning voltammetry with Ep1=-0.70V and a diffusion wave with Ep2=-0.68V (vs. SCE) at pH 2.5. On the surface of HMDE, the adsorption of salieyl-fluorone obeys Frumkin adsorption isotherm. The adsorption coefficient (B), and attractive factor (v) and the amount of saturated adsorption (Γs) have been determined.
SVNTHESES AND CHARACTERIZATION OF TWO HIGH VALENCE VANADIUM COMPLEXES OF SCHIFF-BASE LIGAND WITH RICH PHENOLATE OXVGEN AND THEIR CONVERSION
Jie DAI , Masahiro MIKURIYA
1993, 4(10): 929-930
[Abstract](144) [FullText HTML] [PDF 253KB](1)
Abstract:
Two vanadium complexes of schiff base with rich phenolate oxygen, o-N-salicylideneamino-methylphenol, had been synthesized and characterized. One is a V(Ⅳ) complex with an interaction via vanadyl oxygen and the other is a novel dinuclear V(V, V) complex with an oxo bridge. The conversion between the two complexes had been discussed.
CONDENSATION REACTION OF INACTIVATED BENZENE
Chun Ting SUN , Wei QIU , Ju Zheng LIU , Qi Jun HUANG
1993, 4(10): 931-932
[Abstract](128) [FullText HTML] [PDF 61KB](0)
Abstract:
A new dimolybdenum (V) complex[(C6H4Cl)2C(Ph)]2[Mo2(μ-Cl)3Cl4O2] [Mo2(μ-Cl)2Cl4O2(μ-OCOPh)]has been obtained in the reaction of PhCl with benzoyl peroxide (PhCO2)2 and MoCl5. Its crystal structure has been determined by X-ray diffraction methods. Spectroscopic characterization of the compound and ASED-MO calculation of the trityl cation are reported.
A COMPARISON OF THE DETERMINATION OF STABILITY CONSTANTS OF COMPLEXES OF Cd(Ⅱ) WITH AMINO ACIDS AND SIMPLE PEPTIDES USING MICRO-pH-METRIC TITRATIONS AND CYCLIC VOLTAMMETRY
Ai Ru LU , Leslie D. PETTIT , Gareth BERNARD , Jan E. GREGOR
1993, 4(10): 933-934
[Abstract](265) [FullText HTML] [PDF 91KB](0)
Abstract:
This paper reports the determination of stability constants for complexes of Cd (Ⅱ) with Gly, Ala, Val, Asp, Gly-Asp, Asp Gly, Gly-Gly and Gly-Gly-Gly using both micro-pH-metric titrations and the application of convolution-deconvolution cyclic voltammetry at 25℃ and I=0.10 mol·dm-3 (KNO3). Stability constants were calculated from pH-metric data using the SUPERQUAD computer program and cyclic voltammograms were collected, stored and manipulated using the EG and G CONDECON 300 software. A considerably larger ligand:metal ratio (e, g. 50:1) was possible using voltammetry. Evaluation of results from the two techniques suggests that stability constants for the species[CdL2]and[CdL3]are reliable when calculated fromvoltammetry while those for[CdL]are more reliable when determined by pH-metric titration.
A COMPARISON BETWEEN THE pzc AND iep OF α-FeOOH AQUEOUS SUSPENSION
Zhi Long SHEN
1993, 4(10): 935-936
[Abstract](163) [FullText HTML] [PDF 95KB](0)
Abstract:
The salt titration of goethite (α-FeOOH) aqueous suspension had been carried out with the addition of solid NaCl at several different starting pH values and the point of zero charge (pzc) was estimated. Then the electrophoretic mobilities of positively charged αFeOOH particles dispersed in NaCl solution were measured as a function of pH to obtain the isoelectric point (iep). The two parameters were compared.
CRYSTAL STRUCTURE OF 18-TUNGSTODIVANADATE ANION IN Na2H2[H2V2W18O62].12H2O
Gui Qing HUANG , Shi Wei ZHANG , Mei Cheng SHAO
1993, 4(10): 937-938
[Abstract](146) [FullText HTML] [PDF 83KB](0)
Abstract:
The structure of Na2H2[H2V2W18O62]12H2O has been determined by x-ray analysis. The crystals are trigonal, space group R3m, with cell parameters a=37.613 (11), c=12.972 (7) A, V=15901 (13) A3, and Z=9. The structure model was refined by full-matrix least square to R=0.065 for 1702 reflections with F>4σ (F). The existence of the[H2V2W18O62]4- heteropolyanion in the crystals has been confirmed. It is composed of two VO4 tetrahedra and eighteen WO6 octahedra linked to give the Dawson-type structure.
TWO DIMENSIONAL PROPERTIES OF REVERSED DUCKWEED AMPHIPHILIC POLYMER
Jin WANG , Rui Feng ZHANG , Yue Xia LIANG , Jia Cong SHEN
1993, 4(10): 939-940
[Abstract](143) [FullText HTML] [PDF 107KB](0)
Abstract:
The surface pressure-Area isotherms of Reversed Duckweed amphiphilic polymer were examined in view of their chemical structure and twodimentional properties of polymer monolayer were studied.
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