2000 Volume 11 Issue 6

Determination of Constituents in Hair Dyes by Reversed-phase High-Performance Liquid Chromatography
Bao Hai SHAO , Jian Wei YAN , Xiu Zhu XU , Xiao Yun FU
2000, 11(6): 471-472
[Abstract](157) [FullText HTML] [PDF 93KB](0)
A reversed-phase high-performance liquid chromatographic method for the separation and quantitation of 1,4-phenylenediamine, 4-aminophenol, 3-aminophenol, 1,3-benzendiol and 2,6-phenylenediamine in hair dyes was developed. The separation was carried out on a μ-Bondapak C18 column with methanol-water containing 0.1% triethylamine and 0.02 mol/L NH4Ac (pH=5.20) (10:90, vol./vol.) as the mobile phase. Two real samples were analyzed.
Reduction of Diaryldiselenides by System of Cp2TiCl2/BuiMgBr/THF and Its Application in Synthesis of Unsymmetrical Diaryl Selenides
Xin Hua XU , Xian HUANG
2000, 11(6): 473-474
[Abstract](158) [FullText HTML] [PDF 82KB](0)
Reduction of diaryldiselenides by the system of Cp2TiCl2/BuiMgBr/THF gave the nucleophilic arylselenium complex. They reacted with diaryl iodonium salts to afford unsymmetrical diaryl selenides in high yields.
Study on Unexpected Cycloaddition Reactions of Imines with THF
Jun ZHAO , Ping XIE , Shu Feng CHEN , Xiao Tian LIANG
2000, 11(6): 475-478
[Abstract](165) [FullText HTML] [PDF 122KB](0)
An unexpected tricyclic compound 2,3,3a,4,5,9b-hexahydrophenylfuro[3,2-c] quinoline 4 and its aromatized product 6 were obtained when the cycloaddtion of imine 1 and substituted norbornene 2 was carried out in THF with a catalytic amount of boron trifluoride. The structures of the products were determined by spectral data, and the mechanism of reaction was substantiated by the imitation reaction.
Photoinduced One-Electron Reduction of 1,4-Dihydroxyanthraquinone
Zhi Cheng XU , Jing Yi AN , Yi Zhen HU , Fei TIAN
2000, 11(6): 479-482
[Abstract](165) [FullText HTML] [PDF 171KB](2)
The photoinduced one-electron reduction of 1,4-dihydroxyanthraquinone(1,4-DHAQ) was studied by fluorescence, absorption and ESR spectroscopics.
Michael Additions of Activated Methylene Compounds to α,β-Unsaturated Esters Promoted by Samarium (Ⅲ) Iodide
Xiao Yuan CHEN , Wei Liang BAO , Yong Min ZHANG
2000, 11(6): 483-484
[Abstract](159) [FullText HTML] [PDF 82KB](0)
Promoted by SmI3, β-diketones, β-ketoesters and α-cyano esters were added to α,β-unsaturated esters to form δ-carbonyl esters in mild conditions in moderate to good yields.
Functioned Calix[4]arenes as Artificial Enzymes Catalyze Aldol Condensation
Li LIU , Zu Xing YANG , Yu Liang WANG , Shu Hua CHEN
2000, 11(6): 485-488
[Abstract](160) [FullText HTML] [PDF 124KB](0)
Aldolase models derived from calix[4]arene were designed and synthesized. The aldol condensation of p-nitrobenzaldehyde with acetone was catalyzed by the synthetic enzymes proceeded under mild conditions to offer chiefly aldol-type product in good yield.
The Chemical Reactions of 11-Hydroxycephalotaxine
Chuan Pin ZOU , Ke Mei WU , Liang HUANG
2000, 11(6): 489-492
[Abstract](168) [FullText HTML] [PDF 141KB](0)
Some of the chemical reactions of 11-hydroxycephalotaxine 1, which were encountered during the derivation of 1 and the related compounds were reported.
Synthesis of β-Cyclodextrin Bonded Metal Porphyrins
Zao Ying LI , Cong LI , Xu Ye WU , Yue Ning ZHANG
2000, 11(6): 493-494
[Abstract](154) [FullText HTML] [PDF 99KB](0)
6-Deoxy-6-iodo-β-cyclodextrin (1) reacted with 5-(p-aminophenyl)-10,15,20-triphenyl porphyrin(2), 5-(p-aminophenyl)-10,15,20-triphenyl nickel(Ⅱ) porphyrin[NiTPPNH2P] (3), 5-(p-aminophenyl)-10,15,20-triphenyl manganese(Ⅲ) porphyrin[MnTPPNH2P] (4) and 5-(p-aminophenyl)-10,15,20-triphenyl carbonyl ruthenium porphyrin[Ru(CO)TPPNH2P] (5) to generate the compounds 6-9, respectively. Those new compound 5-9 have been identified by 1H NMR, IR, MS and UV-visible spectra and elemental analysis.
Facile Synthesis of Amidines via Intermolecular Reductive Coupling of Nitriles with Azobenzene Promoted by Samarium Diiodide
Zhi Fang LI , Ping LU , Yong Min ZHANG
2000, 11(6): 495-498
[Abstract](160) [FullText HTML] [PDF 117KB](0)
The intermolecular reductive coupling of nitriles with azobenzene induced by SmI2 was studied. Amidine derivatives were prepared in good yields under neutral and mild conditions.
Synthesis and Properties of New-type Troponoid Dithio-Crown Ethers
Li Jun TANG , Long Yi JIN , Bing Zhu YIN
2000, 11(6): 499-502
[Abstract](150) [FullText HTML] [PDF 118KB](1)
Condensation of 3,7-dichloromethyl-5-isopropyl-2-methoxytropone 4 with bis (mer-captoethyl) ether 5a and mono, di, and tri-ethylene glycol bis(mercaptoethyl) ethers 5b-5d gave troponoid-annexed dithiocrown ethers 6a-6d. Compounds 6a-6d have selective and reversible mercury salt capturing ability.
Study on Synthesis of Heterocycle-Fused Troponoid Compounds
Wen Tao GAO , Zhuo ZHENG
2000, 11(6): 503-504
[Abstract](165) [FullText HTML] [PDF 67KB](0)
3-Acetyltropolone 1 reacted with 3,4,5-trimethoxybenzaldehyde et al. to afford 2~5. 2-Acetyl-7-methylaminotropone 7 reacted with 3,4,5-trimethoxybenzaldehyde et al. to gave 8~10. Compound 1 reacted with 3,4,5-trimethoxybenzaldehyde in the presence of ethyl orthoformate and perchloric acid to afford 6. Compounds 3,5 reacted with hydroxylamine to give 11, 12. The reactions of 3,5 with phenylhydrazine gave 13, 14.
Stereoselective Synthesis and Anticancer Activities of New Podophyllotoxin Derivatives:4-β-Cyano-4-Deoxy-4'-Demethylepipodophyllotoxin and 4-β-Carboxyl-4-Deoxy-4'-Demethylepipodophyllotoxin
Zai Xin CHEN , Wei Yong MA , Chun Nian ZHANG
2000, 11(6): 505-508
[Abstract](172) [FullText HTML] [PDF 129KB](1)
4-β-Cyano-4-deoxy-4'-demethylepipodophyllotoxin 4 was synthesized from 4'-de-methylepipodophyllotoxin and Me3SiCN in the presence of BF3·Et2O. 4-β-Carboxyl-4-deoxy-4'-demethylepipodophyllotoxin 5 was obtained by hydrolyzing 4 in HOAc. Both of them show very high anticancer activities against L1210 and KB cell lines in vitro.
Synthetic Studies of Didemnaketals Analogue-Construction of the Intermediate (3S,5S,6R)-3,7-Dimethyl-5,6,7-trihydroxy-octanal
Yan Xing JIA , Bin WU , Ping Zhen WANG , Yong Qiang TU
2000, 11(6): 509-510
[Abstract](173) [FullText HTML] [PDF 63KB](0)
An efficient and stereoselective synthetic procedure for (3S,5S,6R)-3,7-dimethyl-5,6,7-trihydroxy-octanal derivative, the intermediate for synthetic of the HIV-active didemnaketals analogue, was developed via a series of reactions from the natural (+)-Pulegone. In this approach, an efficient diastereoselective reaction of the epoxides 8 and 9 with PCC has been accomplished.
Synthesis of a New Polysiloxane Containing Octaphenylcyclodisilazane
Ning ZHOU , Zhi Jie ZHANG , Cai Hong XU , Ze Min XIE
2000, 11(6): 511-512
[Abstract](150) [FullText HTML] [PDF 61KB](0)
A new polysiloxane containing octaphenylcyclodisilazane was synthesized from the anionic polymerization of octamethylcyclotetrasiloxane (D4) and "seed solution" as initiator, which was prepared by hexamethylcyclotrisiloxane (D3) and the lithium salt of N,N'-bis (hydroxydi-phenyl)tetraphenylcyclodisilazane.
Total Synthesis of 16-Acetoxy-6,7-didehydroferruginyl Methyl Ether
Yong Hong GAN , An Pai LI , Ping Yan BIE , Xin Fu PAN
2000, 11(6): 513-514
[Abstract](158) [FullText HTML] [PDF 69KB](0)
An efficient synthetic route have been developed to 16-acetoxy-6,7-didehydroferruginyl methyl ether.
Studies on the Preparation of Bioactive Oligomerstilbene by Oxidative Coupling Reaction (I)-Preparation of Shegansu B using Silver Oxide as Oxidant
Li Xin ZHOU , Mao LIN
2000, 11(6): 515-516
[Abstract](160) [FullText HTML] [PDF 81KB](0)
The oxidative coupling reaction of isorhapontigenin using sliver oxide as oxidant afforded a major product, named shegansu B (2), which was isolated from the roots of Belamcanda chinensis (L.) DC. Both the natural and synthetic Shegansu B have the same potent antagonism activities of leukotriene B4, D4 receptor.
Synthesis, Structure and Transesterification of the Derivatives of β-Alkoxycarbonylethyltin Trichlorides with Diethyldithiocarbamate
Lai Jin TIAN , Bin ZHAO , Zheng Yu ZHOU , Min XIA , Wen Tao YU , Ping YANG
2000, 11(6): 517-520
[Abstract](172) [FullText HTML] [PDF 158KB](0)
The derivatives of b-alkoxycarbonylethyltin trichlorides with diethyldithiocarbamate, ROCOCH2CH2Sn(S2CNEt2)Cl2, were synthesized and characterized by the means of elemental analysis, IR, 1H NMR and X-ray single crystal diffraction. The structural features of the compounds were described, and the possible mechanism of transesterification for compound 2a was suggested.
Study of Catalysts on the Synthesis of Methyl Acrylate by Hydroesterification of Methyl Formate with Acetylene
Xin Han HUANG , Xian Gui YANG , Jia Qi ZHANG , Zhao Tie LIU
2000, 11(6): 521-524
[Abstract](163) [FullText HTML] [PDF 137KB](0)
The catalytic hydroesterification of methyl formate (MF) with acetylene to methyl acrylate (MA) over nickel-based catalysts prepared by impregnation has been comprehensively studied in a fixed bed reactor at 160~240℃ and under 4~6MPa, GHSV:630h-1, CO:N2:C2H2=65:28:7. In present work, we have found a catalyst of 11wt%NiO/Al2O3 (80~100 mesh) prepared by wet impregnation with NiCl2 aqueous solution, then calcined in air at 500℃ for 5 h. The selectivity to methyl acrylate and the conversion of methyl formate over 11wt%NiO/Al2O3 catalyst are higher than other catalysts studied in this paper. The optimum reaction temperature for the hydroesterification of methyl formate with acetylene to methyl acrylate is around 220℃.
Synthesis and Characterization of Polyurethane/Poly (Urethane Modified Bismaleimide-Bismaleimide) IPNs
Yuan Li CAI , Peng Sheng LIU
2000, 11(6): 525-526
[Abstract](156) [FullText HTML] [PDF 82KB](0)
PU/P(UBMI-BMI) IPNs with excellent thermal stability and mechanical properties were synthesized and characterized. The interpenetrating occurs in the hard segment domains of PU, which leads to enhancement of hydrogen bonding of N-H, and narrow-distributed small size of the dispersed phase.
Photoinduced Electron Transfer Reaction between Poly-guanylic Acid (5') with Anthraquinone-2-sulfonate
Jian Hua MA , Hua SHAO , Si De YAO , Nian Yun LIN
2000, 11(6): 527-530
[Abstract](173) [FullText HTML] [PDF 181KB](0)
The electron transfer reaction between triplet anthraquinone-2-sulfonate with poly-guanylic acid (5) (poly[G]) in acetonitrile-H2O has been investigated by 248 nm laser flash photolysis. The transient absorption spectra of radical cation of poly[G] and radical anion of anthraqunione-2-sulfonate(AQS) arising from electron transfer reaction has been observed simultaneously for the first time. The formation processes of radical cation of poly[G] and radical anion of anthraquinone-2-sulfonate as well as the decay processes of triplet anthraquinone-2-sulfonate have also been observed, the apparent rate constants for the formation and decay of transient species have been determined. The free energy changes in the process of the electron transfer was also calculated.
The Identification of Two New Sterols from Marine Organism
Shi Hai XU , Long Mei ZENG
2000, 11(6): 531-534
[Abstract](158) [FullText HTML] [PDF 144KB](1)
Two new sterol have been isolated from the South China Sea marine organism. Compound 1 was isolated from the sponge Polymastia sobustia and compound 2 was obtained from the soft coral Sinularia inexplicata. Their structures were established as 3β-hydroxy-stigmast-5en-7-one and 24-methylene cholestan-3β, 6β, 9α, 19-tetrol by variety of spectral analysis such as IR, EIMS, 1DNMR, 1H-1H COSY, HMQC, HMBC, NOESY.
Two New Sterols from Amoora yunnanensis
Xiao Dong LUO , Shao Hua WU , Yun Bao MA , Da Gang WU
2000, 11(6): 535-538
[Abstract](182) [FullText HTML] [PDF 160KB](2)
Two new sterols, 3β,7α,16β-trihydroxy-stigmast-5,22-diene 1, 3β,7α,16β-trihydroxy-stigmast-5-ene 2, were isolated together with two known ergosterols, ergosta-5,24(28)-diene-3β,7α-diol, ergosta-5,24(28)-diene-3β,7β,16β-triol from the bark of Amoora yunnanensis (H. L. Li) C. Y. Wu. Their structures were deduced on the basis of spectral data.
Two New O-terpenoidal Coumarins, Excavacoumarin A and B from Clausena excavata
Hong Ping HE , Yue Mao SHEN , Guo Ying ZUO , Wei Ming ZHU , Xiao Sheng YANG , Xiao Jiang HAO
2000, 11(6): 539-542
[Abstract](169) [FullText HTML] [PDF 133KB](6)
Two new O-terpenoidal coumarins named excavacoumarin A (2), B (3), and a known one 1 were isolated from the leaves of Clausena excavata Burm. f. (Rutaceae) collected in Xishuangbanna, Yunnan. Structure elucidation and unambiguous NMR assignments for the title compounds were carried out on the basis of 1D and 2D NMR experiments.
Two New Bis-tetrahydrofuran Ring Annonaceous Acetogenins from the Roots of Uvaria calamistrata
Guang Xiong ZHOU , Ruo Yun CHEN , Hong CHEN , De Quan YU
2000, 11(6): 543-544
[Abstract](164) [FullText HTML] [PDF 91KB](0)
Two mild-cytotoxic bistetrahydrofuran (THF) ring annonaceous acetogenins named calamistrins F (1) and G (2) were isolated from the ethanolic extract of the roots of U. calamistrata Hance. Their structures including the relative and absolute configurations were determined by chemical derivation and spectral analysis. Calamistrins F and G were a pair of epimers at C-26 which both had THF ring from C-18 to C-25 and three OH groups at C-5, C-17 and C-26.
Photodissociation of Cycloketones by Ultraintense Femtosecond Laser Pulses
Cheng Yin WU , Yi Jia XIONG , Jin Xiong WANG , Fan Ao KONG
2000, 11(6): 545-548
[Abstract](167) [FullText HTML] [PDF 141KB](0)
Photodissociation of cyclopentanone (C5H8O) and cyclohexanone (C6H10O) was studied with 800nm, 50fs laser pulse at intensities of 5.0-13.0×1013 W/cm2. A time of flight mass spectrometer was employed to detect the ion signals. Parent ions dominated at lower laser intensities. Fragmentation of the parent ions increases with increasing laser intensity and molecular size. The fragmentation mechanism was discussed.
The Retention Behaviors of Benzene and Its Alkyl Homologues in Microemulsion Electrokinetic Chromatography
Xiao Yun FU , Wei YUAN , Xiu Zhu XU , Jian De LU
2000, 11(6): 549-550
[Abstract](153) [FullText HTML] [PDF 93KB](0)
The retention behaviors of benzene and its alkyl homologues in microemulsion electrokinetic chromatography were investigated in both anionic and cationic surfactant MEEKC systems. The effects of the composition of microemulsion on retention time and selectivity were studied. A good linear relationship was obtained between log k and the carbon number of alkyl chain.
A New Fluorescent Sensor for Transition Metal Ions in Aqueous Solution
Li Jian JIANG , Zhi Lin WANG , Xiao Qing JIANG , Qin Hui LUO
2000, 11(6): 551-554
[Abstract](137) [FullText HTML] [PDF 168KB](0)
A new fluorescent sensor consisted of fluorenyl and dioxotetraaza unit, namely, 2,10-dimethyl-6-(9-fluorenyl)-1,4,8,11-tetraazaundencane-5,7-dione (L), was synthesized. It is a fluorescent sensor for transition metal ions in aqueous solution.
Structural Multiplicity of Monomers of an Amphiphilic Porphyrin at the Outer Surface of CTAB Micelle
Yun Hong ZHANG , Chen MA , Lin GUO , Qian Shu LI
2000, 11(6): 555-558
[Abstract](131) [FullText HTML] [PDF 162KB](0)
A synthesized amphiphilic porphyrin, 5,10,15-tri(p-hydroxyphenyl)-20-(p-hexadecyl-oxyphenyl) porphyrin, can take a transfer process for the porphyrin moiety from the inner core to the outer surface layer of cetyltrimethylammonium bromide (CTAB) micelle. The increasing of FWHH of the Soret band was attributed to the multiplicity of porphyrin monomers related with deprotonation degree, arrangement, orientation, and position of porphyrin moiety at the surface area rather than the aggregates associated with irregular orientation of neighboring porphyrins.
Growth of Carbon Nanotubes over Ni Nano-particles Prepared in Situ by Reduction of La2NiO4 Oxides
Qi LIANG , Qing LI , Bo Lan ZHANG , Zuo Long YU
2000, 11(6): 559-560
[Abstract](139) [FullText HTML] [PDF 126KB](0)
A novel catalyst precursor, La2NiO4, was investigated to synthesize carbon nanotubes, obtained from catalytic disproportionation of CO. The morphology of carbon nanotubes has been examined by TEM (transmission electron micrograph) and SEM (scaning electron micrograph). It was observed that the Ni nano-particle size formed at different reducing temperatures was a key factor to the yield and diameter of carbon nanotubes.
Application of CO2-TPD in the Synthesis of Composite Oxides from Metal-Organic Precursors
Zong Ping SHAO , Hui DONG , Guo Xing XIONG , Wei Shen YANG
2000, 11(6): 561-564
[Abstract](131) [FullText HTML] [PDF 160KB](0)
CO2-TPD was demonstrated an effective way to investigate the phase formation during pyrolysis for the preparation of composite oxides using metal-organic molecules as precursors. Based on the CO2-TPD results, it was found that calcination condition had deep effect on the carbonate formation and the minimum firing temperature to acquire pure phase composite oxide. An optimized calcination schedule was then developed.
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