2003 Volume 14 Issue 4

Synthesis and Characterization of Poly(ether imide)s Containing m-Methyl and Phthalazinone Moieties
Jin Yan WANG , Shu De XIAO , Xi Gao JIAN
2003, 14(4): 331-332
[Abstract](180) [FullText HTML] [PDF 691KB](0)
Abstract:
Three novel poly(ether imide)s were synthesized by one-step solution polymerization from 2-(3, 4-dicarboxyl-N-phenyl)-4-(3', 4'-dicarboxyl-phenoxyl-4-(2-methyl)-phenyl)-2, 3-phthal-azin-1-one dianhydride and three amines, and characterized. The polymers show good solubility and thermal properties.
A New Solvent-free Synthesis of α,α'-Dibenzylidenecycloalkanones from Acetals with Cycloalkanones under Microwave Irradiation
Dan Feng HUANG , Jin Xian WANG , Yu Lai HU
2003, 14(4): 333-334
[Abstract](179) [FullText HTML] [PDF 691KB](0)
Abstract:
A new rapid synthetic method is described for synthesis of α,α'-dibenzylidene-cycloalkanones by the reaction of acetals and cycloalkanones without solvent using BF3·Et2O as catalyst under microwave irradiation.
Polystyrene-supported Benzyl Selenide:An Efficient Reagent for Highly Stereocontrolled Synthesis of Substituted Olefins
Wei Ming XU , Li Ming YU , Xian HUANG
2003, 14(4): 335-337
[Abstract](172) [FullText HTML] [PDF 855KB](0)
Abstract:
Polystyrene-supported benzyl selenide has been prepared. This novel reagent was treated with LDA to produce a selenium stabilized carbanion, which reacted with alkyl halide, followed by selenoxide syn-elimination, to give substituted olefins stereospecificly.
Study on the Synthesis of Metabolite CM2 of Clausenamide
Xing Zhou LI , Ke Mei WU , Liang HUANG
2003, 14(4): 338-340
[Abstract](176) [FullText HTML] [PDF 886KB](0)
Abstract:
Synthesis of the optically active metabolite of clausenamide CM2 (3, 5-dihydroxy-5-(α-hydroxylbenzyl)-1-methyl-4-benzylpyrrolidin-2-one) from 3-O-acetyl-clausenamide was described.
A Novel Access to Organostannane Compounds under Ultrasound Irradiation
Li Zeng PENG , Tian Sheng MEI , Tao ZHANG , Yu Lin LI
2003, 14(4): 341-342
[Abstract](194) [FullText HTML] [PDF 690KB](1)
Abstract:
A simple and efficient procedure has been developed for the synthesis of organostannane compounds by one-pot reaction of stannane halides, magnesium turnings and organic halides in the presence of 1, 2-dibromoethane under ultrasound irradiation for the first time.
Synthesis and Biological Activities of N-Phosphoryl Branched Peptides
Sheng Li CAO , Yu Yang JIANG , Yu Ping FENG , Yan Ling NIU , Yu Fen ZHAO
2003, 14(4): 343-346
[Abstract](172) [FullText HTML] [PDF 1738KB](0)
Abstract:
A series of N-phosphoryl branched peptides were synthesized by coupling of various N-phosphoryl amino acids to L-Lysine methyl ester, and their structures were confirmed by 31P NMR, 1H NMR, MS and elemental analysis. The results of cell biological tests indicated that compound 1d and 1e obviously inhibited the growth of both K562 and A2780 cells.
A New Technique of Synthesizing 10-Hydroxy-5-methyl-5,10-dihydrophenophosphazine 10-Oxide
Zhi Gang YIN , De Feng ZHAO
2003, 14(4): 347-350
[Abstract](201) [FullText HTML] [PDF 1270KB](0)
Abstract:
10-Hydroxy-5-methyl-5, 10-dihydrophenophosphazine 10-oxide (1) was prepared by a new technique of treating 10-methoxy-5,10-dihydrophenophosphazine 10-oxide (2) with an equivalent of NaH in anhydrous DMF, and then at 120℃ for 3~4 h, which not only avoided poisonous and expensive methyl iodide used in literature, but made the consumption of NaH greatly decrease as well. The possible reaction mechanism was also described. The chemical structure of 1 was confirmed by IR, NMR, and mass spectroscopy.
Studies on a New Usage of Hypophosphorous Acid-iodine System in N-C Bond Cleavage
Ge MENG , Ling ZHAO , You Fu LUO , Fen Er CHEN
2003, 14(4): 351-354
[Abstract](180) [FullText HTML] [PDF 1249KB](0)
Abstract:
A mixture of hypophosphorous acid (H3PO2) and iodine in acetic acid can cleave the N-alkyl bond in a variety of N-1 substituted pyrimidine derivative in relatively high yields, withoutany damage to the amido bond in the non-nucleosides pyrimidine base skeleton.
Henry Reaction in Aqueous Media:Chemoselective Addition of Aldehydes
Cun Liu ZHOU , Yu Qing ZHOU , Zhi Yong WANG
2003, 14(4): 355-358
[Abstract](188) [FullText HTML] [PDF 1417KB](6)
Abstract:
The chemoselective addition of aldehydes in aquoues medium was obtained under mild condition using improved Henry reaction.
An Efficient Synthetic Method of Nordihydroguaiaretic Acid (NDGA)
Ya Mu XIA , Xiao Ping CAO , Kun PENG , Xin Feng REN , Xin Fu PAN
2003, 14(4): 359-360
[Abstract](153) [FullText HTML] [PDF 773KB](0)
Abstract:
Nordihydroguaiaretic acid (NDGA) has been synthesized in nine steps from piperonal using Stobbe condensation as the key step with high yield. By this approach, five relative natural products were obtained.
The Synthesis of Gracillin and Dioscin:Two Typical Representatives of Spirostanol Glycosides
Chuan Chun ZOU , Shu Jie HOU , Ping Sheng LEI , Xiao Tian LIANG
2003, 14(4): 361-364
[Abstract](154) [FullText HTML] [PDF 1520KB](0)
Abstract:
Two spirostanol saponins (gracillin and dioscin) which have the typical sugar moieties were synthesized facilely by a general approach.
An Efficient Process for Preparing 4-Methyl-2-phenyl Piperazine Hydrochloride and its Derivatives
Bai Shu GUO , Yu She YANG , Ru Yun JI
2003, 14(4): 365-367
[Abstract](149) [FullText HTML] [PDF 945KB](0)
Abstract:
An improved method for preparation of 4-methyl-2-phenyl piperazine and its derivatives with higher yield and inexpensive reagents was developed, the products were characterized by 1H-NMR and MS.
Dechlorination of Aromatic Chlorides in Aqueous System Catalyzed by Functionalized MontK10 Supported Palladium-tin
Yu Huan DONG , Qing Zhao MENG , Ru Hong KANG
2003, 14(4): 368-370
[Abstract](170) [FullText HTML] [PDF 1128KB](2)
Abstract:
A novel bisupporter bimetal catalyst PVP-PdCl2-SnCl4/MontK10-PEG400, using for dehalogenation of insoluable aromatic halides in aqueous system, has shown high dechlorination activity and selectivity, without any organic solvent or phase transfer catalyst. The conversion of aromatic chlorides can reach 100%. The catalyst is easy to prepare and has good reusability.
Regioselective Bromination of 3, 4-Dimethoxytoluene with N-Bromosuccinimide
Hong Min MA , Zhan Zhu LIU , Shi Zhi CHEN
2003, 14(4): 371-374
[Abstract](170) [FullText HTML] [PDF 1207KB](0)
Abstract:
The selective brominations of 3, 4-dimethoxytoluene with N-bromosuccinimide were reported. The nuclear and side-chain brominated products were obtained under different reaction conditions. The mechanism was also discussed.
Preparation for Supramolecular Complexes of Chiral Diols BDPDD, DMBDPD and BINOL with Some Prochiral Compounds
De Jun LIU , Zi Xing SHAN , Rong WANG , Jin Gui QIN
2003, 14(4): 375-378
[Abstract](158) [FullText HTML] [PDF 1380KB](0)
Abstract:
Interaction between chiral diols BDPDD, DMBDPD and BINOL with prochiral compounds was examined and some new supramolecular complexes were prepared. It was found that these chiral hosts could include prochiral guests,α,β-unsaturated compounds or piper-azinedione derivatives to give inclusion crystals in different molar ratio. Formations of these supramolecular complexes were characterized by the data of IR and 1H NMR spectra.
A new Furostanoside from Asparagus filicinus
Yan Fang LI , Li Hong HU , Feng Chang LOU , Jian Rong HONG
2003, 14(4): 379-382
[Abstract](157) [FullText HTML] [PDF 1059KB](0)
Abstract:
A new furostanoside, aspafilioside D (1) has been isolated from the root of Asparagus filicinus. Its structure was determined by spectral and chemical methods.
A New Diterpene from Spiraea japonica var. ovalifolia
Guo Ying ZUO , Hong Ping HE , Bin Gui WANG , Xin HONG , Yi Ming HU , Xiao Jiang HAO
2003, 14(4): 383-384
[Abstract](157) [FullText HTML] [PDF 679KB](0)
Abstract:
A new diterpenoid,15-O-acetylspiraminol(1),was isolated from the aerial parts of Spireae japonica L.f.var.ovalifolia.The structure was charaterized mainly based on spectral analysis.
Dissectol A, A Novel Monoterpene Glycoside from Incarvillea dissectifoliola
Wei CHEN , Yue Mao SHEN , Jian Chu XU
2003, 14(4): 385-388
[Abstract](171) [FullText HTML] [PDF 1331KB](1)
Abstract:
Dissectol A, a novel monoterpene glycoside was isolated from the methanol part of the 95% EtOH extract of Incarvillea dissecfoliola and its structure was determined by 1D and 2D NMR data.
Three New Cucurbitacins from Hemsleya lijiangensis
Ming Hua CHIU , Juan GAO
2003, 14(4): 389-392
[Abstract](165) [FullText HTML] [PDF 1128KB](0)
Abstract:
Three new cucurbitacins were isolated from the BuOH extract of the rhizomes of Hemsleya lijiangensis. Their structures were elucidated as 23, 24-dihydro cucurbitacin F-16, 25-diacetate (1), 23,24-dihydro cucurbitacin F-16, 25-diacetate-2-O-β-D-glucopyranoside (2), 23, 24-dihydro-cucurbitacin F-16-acetate (3), respectively; by spectral analyses.
New Eudesmane and Eremophilane Derivatives from Laggera Alata
Qun Xiong ZHENG , Zhao Jun XU , Xian Feng SUN , Françise GUÉRITTE , Michele CESARIO , Christopher H. K. CHENG , Han Dong SUN , Yu ZHAO
2003, 14(4): 393-396
[Abstract](163) [FullText HTML] [PDF 1365KB](0)
Abstract:
From the aerial part of Laggera alata, a novel eremophilanoid (1) as well as two new eudesmanoids (2-3) were isolated. Their structures were elucidated by 2D-NMR technique and X-ray diffraction studies. The cytotoxic activities of these sesquiterpenes were also investigated.
Investigation on the Extraction Mechanism of Au (I) from Cyanide Solution with Quaternary Ammonium System
Jian Zhun JIANG , Wei Hong LI , Wei Jin ZHOU , Hong Cheng GAO , Jin Guang WU , Guang Xian XU
2003, 14(4): 397-400
[Abstract](165) [FullText HTML] [PDF 1596KB](1)
Abstract:
The mechanism of Au (I) extraction has been characterized using 198Au radiometry, thermodynamic equilibrium, Karl-Fischer titration and FT-IR spectroscopy techniques. The results indicate that the extraction follows ionic combination and solvent interaction mechanism. The stoichiometry of the extracted species is 1:1:4:4 for TDMBA+:Au(CN)2-:TBP:H2O. The microstructure model of the extracted complex is a supramolecular structure via hydrogen bonding, ion dipole interaction and ionic combination. The extraction process can be described as micelles in the aqueous phase transfer into the organic phase and reversed micelles or microemulsion (W/O) form in the organic phase.
Influence of Mobile Phase Composition on the Enantioseparation of Methoxyl Flavanones with Self-prepared CDMPC Column and Chiral Recognition Mechanism
Bao Hai SHAO , Xiu Zhu XU , Jian De LU , Li ZOU , Xiao Yun FU
2003, 14(4): 401-403
[Abstract](169) [FullText HTML] [PDF 1350KB](2)
Abstract:
The influence of different alcohol modifiers in mobile phase on the chiral separation of 4'-methoxyl flavanone, 5-methoxyl flavanone and 6-methoxyl flavanone on cellulose tris (3, 5-dimethylphenylcarbamate) (CDMPC) column was studied and the chiral recognition mechanism was discussed. Using hexane-tert-butanol (1.31 mol L-1) as the mobile phase, those three methoxyl flavanones were excellently separated on CDMPC chiral column.
A New Method for Decreasing Mass Limit of Detection and Increasing Number of Theoretical Plates in Capillary Electrophoresis with Amperometric Detection
Xue Mei SUN , Qian Feng WENG , Wen Rui JIN
2003, 14(4): 404-406
[Abstract](163) [FullText HTML] [PDF 875KB](0)
Abstract:
A new method was developed to decrease the mass limit of detection (LOD) and increase the number of theoretical plates (N) in capillary electrophoresis with amperometric detection. When the single microcylinder electrode, the 10 μm ID capillary with the etched detection end and the in-capillary alignment were used, the mass LOD for phenol was reduced 124 times and N was increased 36 times in comparison with the normal situation.
Phase Transition and Micellization of Temperature Responsive Dextran-graft-poly (N-isopropylacrylamide) Polymers
Li Qun WANG , Ke Hua TU , Yu Ping LI , Jie ZHANG
2003, 14(4): 407-410
[Abstract](160) [FullText HTML] [PDF 1423KB](0)
Abstract:
Phase behavior and micellization of dextran-graft-poly (N-isopropylacrylamide) (PNIPAAm) polymers in aqueous solution are investigated in this paper using DSC and AFM methods. It is found that with the increase of grafting (G%) of the copolymers the endothermic enthalpy during the phase transition increases significantly and the transition temperature decreases slightly. The phase transition behavior of the copolymers is scanning rate dependent. Micelles are formed whenever the solution temperature is raised above the LCST of the copolymers. It is proposed that by using this thermal responsive property of the copolymers, drugs could be incorporated into the micelles without employing any organic solvent.
Capacitance Characterization of the Effect of pH Value on the Self-assembled Monolayers of Octadecanethiol
Ke Qiang DING , Qing Fei WANG , Ru Ting TONG , Hui Bo SHAO
2003, 14(4): 411-412
[Abstract](163) [FullText HTML] [PDF 642KB](0)
Abstract:
In this paper, the membrane capacitance (Cm), which was obtained from the electro-chemical impedance spectroscopy (EIS) method, was used to characterize the effect of pH value on the self-assembled monolayers (SAMs) of octadecanethiol(18SH) for the first time. The results not only strongly proved that inorganic ions could penetrate the SAMs of 18SH, but also ascertained that SAMs of 18SH were not an absolute of free of ion-penetration. Verifying the existence of pin-holes in the octadecanethiol SAMs was the main contribution of this paper, which coincided with the former conjecture very well.
Synthesis and Reaction of[MnRe(CO)6(μ-SH)(μ-SC(H)PPr3i)(PPh3)]
Yong Qiang MA , Xiao CHEN , Jing LI , Qing Lan XIE , Hong Gen WANG
2003, 14(4): 413-416
[Abstract](154) [FullText HTML] [PDF 1336KB](0)
Abstract:
The synthesis, the crystal structure and the reaction of the hetero-binuclear complex[MnRe(CO)6(μ-SH)(μ-SC(H)PPr3i)(PPh3)] are reported. The results of single crystal X-ray structure analysis showed that the fragments Mn(CO)3 and Re(CO)3 were bridged by SH and SC(H)PPr3i. The title complexes can react with BunLi and RX forming complexes MnRe(CO)6(μ-SR)(μ-SC(H)PPr3i)(PPh3) (R=Me, CH2CH=CH2, SnBu3n).
Structures and Mechanical Properties of PVC/Na+-Montmorillonite Nanocomposites
Chao Ying WAN , Xiu Ying QIAO , Yong ZHANG , Yin Xi ZHANG
2003, 14(4): 417-418
[Abstract](165) [FullText HTML] [PDF 756KB](0)
Abstract:
Poly (vinyl chloride)/Na+-montmorillonite (PVC/MMT) nanocomposites with different MMT contents were prepared via melt blending. Wide-angle X-ray diffraction (WAXD) and transmission electron microscopy (TEM) were used to characterize the structures. Effects of MMT content on the mechanical properties were also studied. It is found that PVC molecular chains can intercalate into the gallery of MMT layers during melt blending process, the stiffness and toughness of the composites are improved simultaneously within 0.5~7wt% MMT content, and the transparency and mechanical properties decrease as MMT content further increases.
TEM Study on the Formation Process of TiO2 Nanotubes
Jing Wei ZHANG , Xin Yong GUO , Zhen Sheng JIN , Shun Li ZHANG , Jing Fang ZHOU , Zhi Jun ZHANG
2003, 14(4): 419-422
[Abstract](161) [FullText HTML] [PDF 1557KB](2)
Abstract:
The process, that the polycrystalline TiO2 powders were converted into TiO2 nanotubes, was observed with transmission electron microscope. The results obtained indicated that in concentrated NaOH aqueous solution, anisotropic swelling appears on the polycrystalline TiO2 granula at first, and then the nanotubes are formed.
A New Biochemical Way for Conversion of CO2 to Methanol via Dehydrogenases Encapsulated in SiO2 Matrix
Hong WU , Zhong Yi JIANG , Song Wei XU , Shu Fang HUANG
2003, 14(4): 423-425
[Abstract](145) [FullText HTML] [PDF 1118KB](0)
Abstract:
CO2 is converted to methanol through an enzymatic approach using formate dehydro-genase (FateDH), formaldehyde dehydrogenase (FaldDH) and alcohol dehydrogenase (ADH) co-encapsulated in silica gel prepared by modified sol-gel process as catalysts, TEOS as precursor, NADH as an electron donor. The highest yield of methanol was up to 92.1% under 37℃, pH7.0 and 0.3Mpa.
Preparation of Phenolic Resin/Silver Nanocomposites via in-situ Reduction
Lin Jie ZHI , Jin Yue TANG , Tong ZHAO , Yun Zhao YU
2003, 14(4): 425-428
[Abstract](153) [FullText HTML] [PDF 968KB](0)
Abstract:
Resol type phenolic resin/silver nanocomposite was prepared by in-situ reduction method, in which the curing of phenolic resin and the formation of silver nano-particles took place simultaneously. The silver ions were reduced completely to silver nanoparticles, which were dispersed homogeneously in the resin matrix with narrow size distribution.
Preparation of La-Ti Composite Oxide Nanocrystal and Examination of Their Surface Topography with Atomic Force Microscope
Li GU , Yuan Liang WANG , Li Ling TANG , Jiu Jin ZHU , Jun Han WU
2003, 14(4): 429-432
[Abstract](144) [FullText HTML] [PDF 1624KB](0)
Abstract:
With sol-gel method, nanometer La-Ti composite oxide was successfully prepared at a low temperature (750~800℃) using polyethylene glycol as dispersant. By means of atomic force microscope, the surface pattern, particle size distribution, and specific surface area were studied. The compound particle surface appears as a smooth sheet, the mean size of the compound is 25.38 nm. On the specific surface, the particle erects at a height of 4.69 nm. The surface area is 58.90 nm2. The La-Ti composite oxide nanocrystal prefers to narrow and even particle size distribution and the homogeneity of surface topography.
Synthesis, Structure and Conductivity of the New Charge-transfer Salt (ET)2(CH2=CH-CH2-SO3)·H2O
Zhi LIU , Qi FANG , Wen Tao YU , Min Hua JIANG , De Qing ZHANG , Dao Ben ZHU
2003, 14(4): 433-436
[Abstract](143) [FullText HTML] [PDF 1331KB](0)
Abstract:
Electro-oxidation of 3,4,3', 4(-bis(ethylenedithio)-2,2',5,5(-tetrathiafulvalen (abbr. ET) in the presence of allylsulfonate affords a new charge-transfer salt (ET)2(CH2=CH-CH2-SO3)·H2O. The single crystal structure of the title compound is determined to be in orthorhombic crystal system, Pma2 space group. This salt is a semiconductor and its room-temperature conductivity is 0.0489Ω-1·m-1.
Theoretical Investigation on Radical-Coupling Reactivity of Indolinonic Aminoxyls
Hong Yu ZHANG , Lan Fen WANG
2003, 14(4): 437-440
[Abstract](162) [FullText HTML] [PDF 1423KB](1)
Abstract:
Indolinonic aminoxyls can effectively scavenge various radicals by directly coupling with them or by imitating superoxide dismutase. To better understand the radical-coupling reactions, DFT method B3LYP/6-31G(d,p) was employed to calculate variations of free energy for the coupling reactions and other physico-chemical parameters. The radical-coupling activity difference between aminoxyls was elucidated to a large extent in terms of electronic properties of substituents.
Address:Zhongguancun North First Street 2,100190 Beijing, PR China Tel: +86-010-82449177-888
Powered By info@rhhz.net