1997 Volume 8 Issue 12

Asymmetric Trimethylsilylcyanation of Benzaldebyde Catalyzed by Novel Ti(Ⅳ)-Chiral Schiff Base Complexes
Guo Fu ZI , Cheng Lie YIN
1997, 8(12): 1013-1014
[Abstract](270) [FullText HTML] [PDF 90KB](0)
Abstract:
Benzaldehyde has been trimethylsilylcyanated with a catalyst prepared in situ from titanium tetraisopropoxide and chiral Schiff bases.Cyanohydrin is obtained in moderate e.e.values.
Preparation of Chiral Quaternary Ammonium Salts and Initial Study of Asymmetric Phase Transfer Catalytic Alkylation
Rong Liang LOU , Ai Qiao MI , Zhong Yuan ZHOU , Jun Mei ZHANG , Yao Zhong JIANG
1997, 8(12): 1015-1016
[Abstract](185) [FullText HTML] [PDF 94KB](0)
Abstract:
A number of chiral quaternary ammonium salts were synthesized from (1R,2S)-(-)-1,2-diphenyl-2-aminoethanol and applied to the enantioselective alkylation.
Effect of Silyl Moiety on the Reaction of O,O'-Phenylenephosphoryl Chloride with N-Silylvaline Silyl Ester
Qian WANG , Hai Yan LU , Yu Fen ZHAO
1997, 8(12): 1017-1018
[Abstract](176) [FullText HTML] [PDF 97KB](0)
Abstract:
N-Trimethylsilylvaline trimethylsilyl ester Ⅱa,N-triethylsilylvaline triethylsilyl ester Ⅱb and N-tert-butyldimethylsilylvaline tert-butyldimethylester Ⅱc showed evidently different reactivities with O,O'-phenylenephosphorylchloride.The formation speed of the final spiro-bicyclic pentacoordinated phosphorus compounds depends on the intramolecular transfer ability of the silyl oiety crucially.
Asymmetric 1,3-Dipolar Cycloaddition of the Chiral Nitronic Esters with Acrylate
Fu An KANG , Cheng Lie YIN
1997, 8(12): 1019-1020
[Abstract](174) [FullText HTML] [PDF 117KB](0)
Abstract:
Asymmetric 1,3-dipolar cycloaddition of the chiral nitronic esters with acrylate giving the enantiomerically pure novel chiral bisheterocyclic compounds is described.
Synthesis of 3-Substituted-6-(2,4-Dichlorophenyl)-s-Triazolo[3.4-b]-1,3,4-Oxadiazoles
Xiao Ming FENG , Xun HE , Yao Zhong JIANG
1997, 8(12): 1021-1024
[Abstract](178) [FullText HTML] [PDF 165KB](0)
Abstract:
Fourteen new 2-acylhydrazino-5-(2,4-dichlorophenyl)-1,3,4-oxadiazoles were prepared by nucleophilic displacement of acylhydrazine at the 2-position of 2-methylsulfonyl-5-(2,4-dichlorophenyl)-1,3,4-oxadiazole.Fourteen new 3-substituted-6-(2,4-dichlorophenyl)-s-triazolo[3,4-b]-1,3,4-oxadiazoles were obtained by treating 2-acylhydrazino-5-(2,4-dichlorophenyl)-1,3,4-oxadiazoles with K2CO3 solution.All the new compounds showed significant antibacterial activity.
Synthesis of Macrocycles Containing Amino Acid Ester and Aryl-heterocyclic Units
Yan Tao CHEN , Wen Ting HUA , Qi Yi XING
1997, 8(12): 1025-1028
[Abstract](177) [FullText HTML] [PDF 131KB](0)
Abstract:
Four kinds of new macrocycles containing amino acids and aryl-heterocyclic units were synthesized by the condensation of di-esters containing Ts-amino acids units with di-halogenated compounds at room temperature.The macrocycles were characterized by elemental analysis,IR,MS(FAB) and 1H NMR.
Synthesis of D-Fructofuranosides Using Phenyl Thioglycosides as Glycosyl Donors
Jun XUE
1997, 8(12): 1029-1030
[Abstract](267) [FullText HTML] [PDF 99KB](0)
Abstract:
Benzoylated phenyl α-and β-2-thio-D-fructofuranosides were synthesized and firstly used as donors in coupling with sucrose acceptor.α-Fructofuranoside was stereospecifically synthesized by employing NIS (N-iodosuccinimide)/AgOTf as catalysts.The structure of all products was confirmed by 13C-NMR or 1H-NMR spectrum.
Sythesis of 4,5-Bisaryl-2-(2,5-Dimethylthiophen-3-yl) imidazoles and Their Dimers
Jin Quan BAI , Xiao Chun HAN , Yong Mei WANG , Ji Ben MENG
1997, 8(12): 1031-1032
[Abstract](185) [FullText HTML] [PDF 71KB](0)
Abstract:
4,5-diphenyl,4,5-bis(4-methylphenyl),4,5-bis(4-methoxyphenyl)-2-(2,5-dimethylthiophen-3-yl) imidazoles were synthesized.Oxidation of the obtained imidazoles with potassium ferricyanide in water-alcohol solution of alkali gave the corresponding dimers.The structures of imidazoles were characterized by IR,1H NMR,mass spectroscopy and elemental analysis.The structures of dimers were characterized by IR,elemental analysis and chromatography.
Synthesis and Structure of 1,2-O-(1-Aryl-1-Propylidene)-D-Mannitol
Jian Hua YU , Yu Lai HU , Wen Fei TAN , Shi Yan YANG , Yuan Qi YIN
1997, 8(12): 1033-1036
[Abstract](178) [FullText HTML] [PDF 149KB](0)
Abstract:
A method for selective reaction of 1-aryl-propane-1-ones with 1,2-dihydroxy group of D-mannitol in the presence of ZnCl2-BF3.Et2O to 1,2-O-(1-aryl-1-propylidene)-D-mannitol (1-4) is described.The compounds were first reported and determined by IR,MS,1H-/13C-NMR spectra,among them the structure of 1 was further defined by X-ray diffraction.
Total Synthesis of Gnetifolin A
Dao Fei HUANG , Xiang ZHANG , Shu Feng CHEN
1997, 8(12): 1037-1040
[Abstract](172) [FullText HTML] [PDF 156KB](0)
Abstract:
Total synthesis of gnetifolin A was accomplished via intramolecular Wittig reaction.The synthesis started from 2-methoxy-3-methylhydroquinone and methyl 4-O-methylgallate through eight steps.
Study on the Total Synthesis of 3-Oxo-9β-Acetoxyilicic Acid-The Synthesis of 9β-Acetoxy-3(4),11(13)-Dien-5αH,7αH-12-Eudesmanoic Acid Methyl Ester
Jiong YANG , Zhao Ming XIONG , Yong Gang CREN , Yu Lin LI
1997, 8(12): 1041-1042
[Abstract](174) [FullText HTML] [PDF 94KB](0)
Abstract:
The synthesis of 9β-acetoxy-3(4),11(13)-dien-5αH,7αH-12-eudesmanoic acid methyl ester (2) was achieved from oxycarvone.The key step is the p-toluenesulfonhydrazide assisted reductive rearrangement reaction.
Studies on the Total Synthesis of Hainanolide (Ⅳ)-Revising the Stereochemistry of C2a-H and Introducing the Two Hydroxy Groups at C,C Positions
Wen Qian YANG , Xiao Ming YU , Shi Zhi CHEN , Liang HUANG
1997, 8(12): 1043-1044
[Abstract](187) [FullText HTML] [PDF 75KB](0)
Abstract:
Tricyclic compound 6 was synthesized from compound 1 through six steps,thus problem of the stereochemistry of C2a-H being solved.The stereochemistry for introducing hydroxy groups at C and C positions in compound 1 was also described.
Copolymerization of N-Phenylmaleimide with Cyclohexene
Hua Ming LI , Hong Biao CHEN , Zhong Ming JIANG , Peng Sheng LIU
1997, 8(12): 1045-1046
[Abstract](181) [FullText HTML] [PDF 77KB](0)
Abstract:
Radical copolymerization of N-phenylmaleimide with cyclohexene was carried out with 2,2-azobisisobutyronitrile in various solvents at 60℃.The copolymer was characterized by IR and 1H-NMR.
Novel Phosphonoacetic Acid Derivatives. Synthesis of N-(Ethoxycarbonylmethylphosphonyl)-α-Amino Esters and-α-Amino Phosphonic Acid Esters and Their Bioactivities
Hui Ying LI , Kang Tai REN , Ru Yu CHEN
1997, 8(12): 1047-1050
[Abstract](186) [FullText HTML] [PDF 182KB](0)
Abstract:
A series of novel phosphonoacetic acid derivatives,N-(ethoxycarbonylmethyl-ethoxyphosphonyl)-α-amino acid esters and α-amino phosphonates,were synthesized via the reaction of the corresponding phosphonyl chloride with amino acid ester hydrochlorides or amino phosphonates in the presence of a base.The preliminary bioassay shows that some compounds show significant anti-viral activity against tobacco mosaic virus (TMV).
Reactivity of C-10 Function in Sinenxan A and Its Derivatives
Fen Mei YAO , Dong Hui WANG , Guang Yan HUANG , Ji Yu GUO , Xiao Tian LIANG
1997, 8(12): 1051-1054
[Abstract](179) [FullText HTML] [PDF 188KB](0)
Abstract:
The allylic nature of C-10 in sinenxan A (1) leads to facile SN1 and elimination reactions.
A New Taxoid from Microbial Transformation
Hong XU , Ke Di CHENG , Wei Shuo FANG , Ping ZHU , Chao MENG
1997, 8(12): 1055-1056
[Abstract](192) [FullText HTML] [PDF 86KB](0)
Abstract:
A new taxoid taxa-4(20),11-diene-2α,5α,10β,14β-tetraol-2α,14β-diacetate (sinenxan H) (1) was obtained by biotransformation of taxa-4(20),11-diene-2α,5α,10β,14β-tetraol-2α,5α,10β,14β-tetraacetate (2) with a fungus isolated from Taxus yunnanensis.Its structure was determined based on spectral data.
A New Taxoid from the Needles of Taxus×media Hicksii
Yong Li GAO , Jin Yun ZHOU , Yi Ding , Qi Cheng FANG
1997, 8(12): 1057-1058
[Abstract](183) [FullText HTML] [PDF 79KB](0)
Abstract:
A new taxoid with 5/7/6 taxane skeleton,named taxamedin A (1) was isolated from the needles of Taxus×media Hicksii.Its structure was elucidated by spectral analysis.
Artselenin, a New Guaianolide from Artemisia selengensis
Jin Feng HU , Xiao Zhang FENG
1997, 8(12): 1059-1060
[Abstract](192) [FullText HTML] [PDF 89KB](0)
Abstract:
Artselenin,a new guaianolide isolated from Artemisia selengensis and its structure determination by spectral data are reported.
Two New Diterpenoids from Isodon Lungshengensis
Bei JIANG , Xing Rong CHEN , Ze Qin LU , Zhong Wen LIN , Han Dong SUN
1997, 8(12): 1061-1062
[Abstract](180) [FullText HTML] [PDF 112KB](0)
Abstract:
Two new diterpenoids,lungshengenin B and C (1-2),were isolated from Isodon lungshengensis.The structures were determined as 1α-hydroxy-2β,3β,11β,15β-tetraacetoxy-ent-kaur-16-en-6-one;11α-hydroxy-2β,3β,6α-triacetoxy-ent-kaur-16-en-15-one by 1D and 2D NMR techniques (COSY,HETCOR,COLOC).
Use of Magic Angle Spinning 1H NMR Spectroscopy to Monitor Reactions in Solid-Phase Synthesis
Ai Ming YU , Hua Zheng YANG , Ping Chuan SUN , Zhen Pu ZHANG , Ming LI
1997, 8(12): 1063-1064
[Abstract](177) [FullText HTML] [PDF 89KB](0)
Abstract:
Proton NMR-spectra of Wang resin bound compounds were obtained using the magic angle spinning 1HNMR technique with standard equipment.It was possible to analyse the spectra to evaluate their utility in solid-phase chemistry.A typical example was presented,which could directly monitor solid-phase reactions.
Determination of Vitamin D2 and Vitamin D3 in the Caltrate Weikang Capsules by HPLC
Qing Tao PENG , Wen Xiang HU , Sheng Jian TAN , Pei Rang CHEN , Xiang Xian ZHANG
1997, 8(12): 1065-1068
[Abstract](190) [FullText HTML] [PDF 131KB](0)
Abstract:
The Caltrate Weikang capsules made by us is a high potency calcium preparation,in which vitamin D can promote the body's calcium absorption and the bones calcification.A sensitive HPLC method for the determination of VD2 and VD3 in Caltrate Weikang capsules was established and VD stability was also examined.
Synthesis of 1-(4-Antipyrinyl)-3-(3-Chlorophenyl)-Triazene and Its Colour Reaction with Mercury
Zhi Gang SHE , Chu Ru GoNG , Yi LUO , Ming Hua YANG
1997, 8(12): 1069-1070
[Abstract](192) [FullText HTML] [PDF 106KB](0)
Abstract:
A new diazoamino reagent 1-(4-antipyrinyl)-3-(3-Chlorophenyl)-triazene(APCPT) was synthesized.The colour reaction of APCPT with Hg(Ⅱ) was studied.At pH=10.5~12.2,in the presence of Tween-80,APCPT reacts with Hg(Ⅱ) to form a red complex with high sensitivity.The molar ratio of Hg(Ⅱ) to APCPT is 1:2.The molar absorptivity is 1.87×105L·mol-1·cm-1.Beer's law is obeyed for Hg in the range of 0-16μg/25ml.
The Electrochemical Impedance Behavior of the Living Cells Escherichia Coli
Wei LI , Jun FENG , Hua Quan YANG , Yun Xiang CI
1997, 8(12): 1071-1072
[Abstract](182) [FullText HTML] [PDF 104KB](0)
Abstract:
The semiconductive characteristics of electron-transferring proteins in living cells E.coli was investigated by electrochemical impedance spectroscopy (EIS).We found that the electrochemical impedance of living cells as a function of temperature followed the Arrhenius equation for semiconductors.This result shows a strong evidence to prove the semiconductive behavior of proteins.
Ab initio Study on the Interaction of La (Ⅲ) with Adrenaline
Zhi Jian WU , Qing Bo MENG , Feng GAO , Chun Ji NIU , Si Yuan ZRANG
1997, 8(12): 1073-1074
[Abstract](177) [FullText HTML] [PDF 85KB](0)
Abstract:
The interaction of La(Ⅲ) with adrenaline was studied using Ab initio method.The geometry of the complex of La (Ⅲ) with adrenaline was optimized,and the La(Ⅲ) bonding site in adrenaline was ascertained.
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