1997 Volume 8 Issue 7

Cyclopropanation of 1, 1-Dichloro-4-methyl-1,3-pentadiene with Diazoacetate
Zheng Ning LI , Zhi Xiu XU , Hui Lin CHEN , Zhuo ZHENG , Yun XU , Xin Quan HU
1997, 8(7): 559-562
[Abstract](170) [FullText HTML] [PDF 111KB](0)
Abstract:
Several cyclopropanation catalysts for the synthesis of 3 (2,2-dichlorovinyl)-2,2.dimethylcyclopropanecarboxylates have been studied in this paper.Owing to electron deficiency of 1,1-dichloro-4-methyl-1,3-pentadiene,yield of this reaction is rather low compared with that of 2,5-dimethyl-2,4-pentadiene.Of all catalysts concerned,yield ranged from 25.1% to 47.2%.
Intermolecular [4+3] Cycloaddition of Cyclic Oxyallyl
You Hong HU , Dong Lu BAI
1997, 8(7): 563-564
[Abstract](173) [FullText HTML] [PDF 106KB](0)
Abstract:
The [4+3] cycloaddition of the 6-substituted-2-chlorocyclohexanone and furans under the Fohlish conditions (Et3N in CF3CH3OH) has been accomplished to give tricyclic cycloadducts with good yields.
Addition of Per(poly) fluoroalkyl Iodides to vinyl Cyclopropane Derivatives:Synthesis of Fluoroalkyl Substituted γ, δ-Unsaturated Carbonyl Compounds
Qiao Sheng HU , Chang Ming HU
1997, 8(7): 565-568
[Abstract](168) [FullText HTML] [PDF 125KB](0)
Abstract:
In the presence of CrCl3/Fe bimetal couple,per(poly) fluoroalkyl iodides add to vinyl cyclopropane compounds giving addition-ring-opening products in good yields.
Synthesis of Schiff Base Type Macrocycles Containing Naphthalene Ring
Chang Rong NIU , Hai Ning ZHANG , Cheng Tai WU
1997, 8(7): 569-572
[Abstract](177) [FullText HTML] [PDF 132KB](1)
Abstract:
A series of new Schiff base type macrocyclic crown ethers containing naphthalene ring were synthesized from 2,2'-di(o-formylnaphthoxy) ethyl ether or 1,2-di(o-formylnaphthoxy)ethane and four appropriate diamines.The chemical structures of the new compounds were characterized by elemental analysis,infrared spectra,nuclear magnetic resonance spectra and mass spectrometry.
A Simple and Efficient Procedure for the Preparation of O-aryl-O-ethyl-S-allyl Thiolophosphates
Li Ming HU , Zan Kai YAN , Wei Bin CHEN , Zhao Jie LIU
1997, 8(7): 573-576
[Abstract](171) [FullText HTML] [PDF 117KB](0)
Abstract:
The thiono-thiolo allylic rearrangement of O-allyl-O-aryl-O-ethyl thionophosphates(1a-j) adsorbed on SiO2 afforded the corresponding O-aryl-O-ethyl-S-allyl thiolophosphates (2a-j) in good yields.
Synthesis of 1,2,3,4-Tetrahydro-1-Indolizinones and 3-Methyl-1,2-dihydro-1-Pyrrolizinones
Ji Yun LIU , Shou Fang ZHANG
1997, 8(7): 577-578
[Abstract](184) [FullText HTML] [PDF 104KB](0)
Abstract:
4-(1-Pyrrolyl) butanenitrile (4),the key intermediate for the synthesis of 1,2,3,4-tetrahydro-1-indolizinone,was prepared with Clauson-Kass reation.When pyrrole reacted with 4-bromobutanenitrile in PEG-400 dimethyl ether catalyzed by NaOH,3-(1-pyrrolyl) butanenitrile was obtained.The nitrites were converted into the corresponding ketones by Hoesch reaction.Some of the ketone derivatives were prepared.
A Novel Calix [4] arene Having Long-Chain Monoalkenyl at The Upper Rim
Xue Ran LU , Xing Hua TANG , Shu Ling GONG , Yuan Yin CHEN
1997, 8(7): 579-582
[Abstract](174) [FullText HTML] [PDF 111KB](0)
Abstract:
5-1',1'-dimethylundecenyloxyphenylmethyl-11,17,23-tris-1",1"-dimethylethyl-25,26,27,28-tetrahydroxycalix [4] arene was synthesized from 1,1-dimethylundecenyoxylphenyl-methylphenol (3) and bishydroxymethylated p-tert-butylphenol-formaldehyde trimer (7) (3-[3-[3-(Hydroxymethyl)-5-tert-butylsalicyl-5]-tert-butylsalicy]-5-tert-butyl-2-hydroxybenzyl Alcohol) by ‘1+3’ fragment condensation in dioxane with TiCl4 as condensation agent in 28% yield.It is the first long-chain monoalkenyl substituted calix [4] arene in which the alkenyl was attached to the upper rim of calix [4] arene.
Synthesis of 2-Fluoroalkylated Tetrahydrofuran Derivatives from Ethyl α-Fluoroalkylacetates
Bing Hao LUO , Hui Ping GUAN , Quan Fu WANG , Chang Ming HU
1997, 8(7): 583-586
[Abstract](176) [FullText HTML] [PDF 137KB](0)
Abstract:
Ethyl α-(2-alkenyl)-α-perfluoroacylacetates (4) are synthesized from the reaction of ethyl α-perfluoroalkylacetates with allylic alcohols in the presence of the mixed base of triethylamine and sodium dicarbonate.lodoenoletherification of the compounds 4 afforded 2-fluoroalkylated tetrahvdrofuran derivatives 5 under the improved conditions.The possible reaction pathways are suggested.
Synthesis of Novel Polypyridine Ligands
Bing Wen JING , Man Hua ZHANG , Tao SHEN
1997, 8(7): 587-590
[Abstract](183) [FullText HTML] [PDF 182KB](0)
Abstract:
Some novel polypyridine ligands containing adsorbing groups were synthesized with the purpose of developing new ruthenium(Ⅱ) polypyridine complexes to be used in solar cell based on dye-sensitized nanocrystilline TiO2 film electrode.
A New Route to S-(-)Zearalenone
Zhi Qin WANG , Shi Ka TIAN
1997, 8(7): 591-594
[Abstract](177) [FullText HTML] [PDF 133KB](0)
Abstract:
A concise synthesis of naturally occurring S-(-)-zearalenone has been described.
The First Total Synthesis of Five Elegan Type Natural Products
Jing LI , Jiong LAN , Zuo Sheng LIU , Yu Lin LI
1997, 8(7): 595-598
[Abstract](167) [FullText HTML] [PDF 150KB](0)
Abstract:
The first total synthesis of five linear diterpenes:eleganolone (1),eleganolone acetate (2),elegandiol (3),eleganonal (4) and epoxyeleganolone (5),was achieved from (E,E)-farnesol (6) via 4 to 6 steps.The key step was the alkylation reaction of silyl cyanide with allylic iodide.
Five New Flavonoids from Bidens Pilosa L. Var. Vadiata SCH.-BIP
Jia WANG , Hui YANG , Zhong Wen LIN , Han Dong SUN
1997, 8(7): 599-602
[Abstract](178) [FullText HTML] [PDF 205KB](0)
Abstract:
Five new flavonoids were isolated from the aerial parts of Bidens pilosa L.var.vadiata Sch.-Bip..Their structures were established on the basis of spectroscopic methods.
Four New Compounds from Isodon Eriocalyx
Jia WANG , Zhong Wen LIN , Tetsuro SHINGU , Han Dong SUN
1997, 8(7): 603-606
[Abstract](176) [FullText HTML] [PDF 137KB](0)
Abstract:
Four new diterpenoids named maoecrystal Q-T (1-4) were isolated from the dried leaves of Isodon eriocalyx.Their sturctures were established by spectroscopic methods.
Studies on an Immune Active Dodecapeptide Isolated from the Buckwheat Pollen
Yan Ling SONG , Xia WANG , Shu Wen HE , Sheng JIN , Jun Da LIU , Shu WANG
1997, 8(7): 607-610
[Abstract](178) [FullText HTML] [PDF 153KB](0)
Abstract:
A new basic dodecapeptide BPP was isolated from the water-extract of the buckwheat pollen (BP).The sequence of BPP,which was first reported,was determined by DABITC/PITC double coupling method,and confirmed by chemical synthesis.Some analogues of BPP were also synthesized by SPPS Method.The effect of these peptides on spleen lymphocytes from mice of Kunming inbred line and on release of SIL-2R from human lymphocytes were studied.The results showed that these peptides exhibit certain immune activity.
Regulation of Cleavage Activity of Ser-His Dipeptide on DNA by Phosphorylation
Xiang Hong LI , Yu Fen ZHAO
1997, 8(7): 611-612
[Abstract](170) [FullText HTML] [PDF 74KB](0)
Abstract:
The cleavage reactions of Ser-His and its N-terminal phosphorylated form-N-(O,O-diisopropyl) phosphoryl seryl-histidine (DIPP-Ser-His) were studied on DNA.It was found that the phosphorylation of Ser-His caused the lost of the cleavage activity on DNA.The result might give some clue on the regulation of the activity of protein by phosphorylation.
Complex Formation between Heptakis(2,3,6-tri-O-butyl)-β-cyclodextrin with p-Nitrophenol in Heptane
Le Xin SONG , Bao Long LI , Rong JIANG , Jian Gang DING , Qing Jin MENG
1997, 8(7): 613-614
[Abstract](177) [FullText HTML] [PDF 130KB](0)
Abstract:
Heptakis (2,3,6-tri-o-n-butyl)-β-cyclodextrin (TB-β-CD) has been found to form an inclusion compound with p-nitrophenol in heptane.The stability constant of the inclusion compound of p-nitrophenol with TB-β-CD in heptane is an order of magnitude greater than that in water.
A modified soft docking method for proteins and peptides
Jun Mei WANG , Li Rong CHEN , Fan JING , Xiao Jie XU
1997, 8(7): 615-618
[Abstract](176) [FullText HTML] [PDF 162KB](0)
Abstract:
A modified two-stage soft-docking procedure was developed for the theoretic researches on the recognition of protein-protein or protein-peptide complexes.Some systems have been used to test our program and the results are encouraging.
Quantitative analysis of two analgesic formulations by micellar electrokinetic chromatography
Bi Yun SUN , Ai Jin HUANG , Yi Liang SUN , Zeng Pei SUN
1997, 8(7): 619-622
[Abstract](166) [FullText HTML] [PDF 223KB](0)
Abstract:
A micellar electrokinetic chromatographic (MECC) method with sodium cholate as pseudostationary phase was proposed for the separation and quantitation of two analgesic formulations containing acetaminophen,dextro-methorphan hydrobromide,phenylpropanolamine hydrochloride,and chlorpheniramine maleate.The internal standard method was proved to be able to yield satisfactory results even with a modular CE instrument with RSD between 0.6~2.1%,and recoveries ranging from 98.1~99.9%.
Artificial Neural Networks Applied to Gas Mixture Analysis
Yong Jing LIN , Er Yi ZRU , Peng Yuan YANG
1997, 8(7): 623-626
[Abstract](173) [FullText HTML] [PDF 195KB](0)
Abstract:
An array composed of sixteen gas sensors was constructed to analyze gas mixtures quantitatively.The data of responses from the sensor array to ethane,propane and propylene were treated by three-layer ANN with BP algorithms and PLS.The analytical results indicated that the concentration predicted with ANN is better than that with PLS.The average prediction errors for ethane,propane and propylene were 5.11%,8.28%,2.64%,respectively.
Study on the Application of Gibberellin for the Spectrophotometric Determination of Arsenic,Phosphorus,Silicon and Germanium®
Yu Biao WANG , Qian Rong LI
1997, 8(7): 627-628
[Abstract](116) [FullText HTML] [PDF 129KB](0)
Abstract:
In the media of 0.66,0.96,2.16 and 0.54 mol/L of H2SO4,the heteropoly acids of As,P,Si and Ge are separately reduced to corresponding heteropoly blues by gibberellin,which exhibit maximum absorptions at 835,820,810 and 805 nm with molar absorptivities of 2.64×104,2.54×104,3.51×104 and 2.25×104 L·mol-1·cm-1 and linear ranges of 0-30,0-15,0-10 and 0-30 μg/25mL,respectively.The method was applied to the determinations of As,P and Si in alloyed steel.
Electron Impact Mass Spectrometry of Acylaminotetraoxyphosphorane
Nan Jing ZHANG , Hai Yan LU , Xin CHEN , Yu Fen ZHAO
1997, 8(7): 629-632
[Abstract](170) [FullText HTML] [PDF 120KB](0)
Abstract:
The electron impact ionization mass spectral fragmentations of a series of acylaminotetraoxyphosphoranes were investigated.The results showed that EIMS of such compounds exhibited very characteristic fragmentation patterns,which would provide useful clues for the structural assignment of this type of compounds.
Luminescence Properties of the Ternary Terbium Complexes with (Ortho and Para) Aminobenzoic acids and 1,10-Phenanthroline Incorporated in Silica Matrix by a Sol-gel Method
Bing YAN , Hong Jie ZHANG , Shu Bin WANG , Jia Zuan NI
1997, 8(7): 633-636
[Abstract](170) [FullText HTML] [PDF 170KB](0)
Abstract:
Ternary complexes of terbium with ortho (and para) aminobenzoic acid and 1,10-phenanthroline were introduced into silica gel by the sol-gel method.The luminescence behavior of the solid-state samples was studied during the sol-gel aging process by means of emission,excitation spectra,lifetimes and quantum efficiencies.
Polymerization of Methyl Methacrylate by Diisopropylamido bis(methylcyclopentadienyl) ytterbium Complex
Li Sheng MAO , Ming Qiang XUE , Qi SHEN
1997, 8(7): 637-638
[Abstract](173) [FullText HTML] [PDF 109KB](0)
Abstract:
It was first found that diisopropylamido bis(methylcyclopentadienyl) ytterbium complex (MeCp)2YbN(i-Pr)2(THF) exhibits extremely high catalytic activity in the polymerization of methyl methacrylate.The reactions can be carried out over a quite broad range of polymerization temperatures from-78℃ to 40℃.The results of GPC (gel permeation chromatography) indicate that the molecular weight distribution (Mw/Mn) becomes broad with the increase of temperature.
Polymerization of Phenyl Isocyanate by Divalent Samarium Complex (ArO)2Sm(THF)4 (ArO=2,6-di-tert-butyl-4-methylphenoxo)
Fu Gen YUAN , Qi SHEN
1997, 8(7): 639-640
[Abstract](178) [FullText HTML] [PDF 96KB](1)
Abstract:
Phenyl isocyanate was for the first time successfully polymerized by divalent samarium complex (ArO)2Sm(THF)4.The monomer concentration and temperature affected the polymerization greatly.
Tb(Ⅲ) and Ca(Ⅱ) Ion Equilibria in the Presence of Glutamic Acid and Glutamine
Chun Ji NIU , Shu Fu ZHAO , Yue Ting MA , Hui ZHAO , Yan Min LIU , Shu Gong ZHANG , Jia Zuan NI
1997, 8(7): 641-642
[Abstract](196) [FullText HTML] [PDF 87KB](0)
Abstract:
Tb(Ⅲ) and Ca(Ⅱ) ion equilibria in the presence of glutamic acid and glutamine were studied by potentiometric titration at 37℃ and an ionic strength of 0.15mol/L(NaCl).The stability constants for Tb(Ⅲ) and Ca(Ⅱ) complexes in the systems were obtained.The species and their distribution in the systems were discussed.
Synthesis and Luminescence Properties of Barium Fluorotungstate Phosphors
Shui Jin YANG , Ju Tang SUN , Zi Bin QIN
1997, 8(7): 643-644
[Abstract](167) [FullText HTML] [PDF 106KB](0)
Abstract:
The investigation of the system BaF2-WO3 revealed the existence of a fluoro-tungstate formulated as Ba2WO3F4.The Ba2WO3F4 was prepared with the solid state reaction method.Under UV or X-ray excitation,Ba2WO3F4 exhibits a very strong blue-green emission peaking at 480 nm at room temperature.The luminescence properties are similar to those of the tungstate,especially MgWO4.
Ab Initio Potential Surface in CH4 Activation by PTCL2
Fu Jiang DING , Liang Fu ZHANG
1997, 8(7): 645-646
[Abstract](148) [FullText HTML] [PDF 93KB](0)
Abstract:
Ab initio potential surface of oxidative addition of CH4 to coordinatively unsaturated PtCl2 is presented.The electron correlation has a big effect on the transition state and activation energy.
Ab initio Structure Determination of [Co(NH3)5Br]Br2 Using Conventional X-ray Powder Diffraction
Hong Xiang WU , Li Dun MA
1997, 8(7): 647-648
[Abstract](148) [FullText HTML] [PDF 95KB](0)
Abstract:
The crystal structure of [Co(NH3)5Br]Br2 has been determined ab initio from the conventional X-ray powder diffraction data.The approximate structure with all 7 independent non-H atoms was solved by direct methods.The final orthorhombic unit-cell parameters after Rietveld refinement are:a=13.6927,b=10.7071,c=6.9400Å,V=1017.47Å3,F30=93(0.0075,43),M20=49,Z=4.Space group is Pnma.The structure agreement factors are:Rp=0.066,Rwp=0.090,RF=0.041,RB=0.042.
Synthesis of Mesoporous Molecular Sieve MCM-41 in Extremely Dense System
Guang Huan LIU , Rui Juan GAO , Hong XU , Jin Xiang DONG
1997, 8(7): 649-652
[Abstract](143) [FullText HTML] [PDF 154KB](0)
Abstract:
Mesoporous molecular sieve MCM-41 has been synthesized in the extremely dense system (with H2O/Si < 10) and characterized by XRD,N2 adsorption isotherm as well as probe reactions of cracking of cumene and isomerization of o-xylene.
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