1999 Volume 10 Issue 9

Enantioselective Addition of Diethylzinc to Benzaldehyde by Catalysts of Chiral Heterocyclic Ligands
Yan HE , Yue Lan LI , Ye Di GUAN
1999, 10(9): 717-718
[Abstract](153) [FullText HTML] [PDF 62KB](0)
Several kinds of chiral heterocyclic ligands without hydroxyl group have been synthesized and used as catalysts for the asymmetric addition of diethylzinc to benzaldehyde. These ligands promoted the formation of (S)-l-phenylpropanols in good yields and medium to good enanlioselectivities(50~86%ee.)
N,N-Di-isopropyl-O,O-Di-p-methoxybenzylphosphoramidite——A New Phosphorylating Reagent
Shoichirol OZAKI , Ai You HAO , Xiang Zheng KONG , Da Xing ZHENG
1999, 10(9): 719-722
[Abstract](164) [FullText HTML] [PDF 138KB](0)
A new phosphorylating reagent, N,N-di-isopropyl-O,O-di-p-methoxybenzylphosphor-amidite was synthesized from diisopropylamino dichlorophosphine and p-methoxybenzyl alcohol for preparing phosphatydyl inositol polyphosphate particularly with unsaturated components.
Synthesis of Aminomethyl Arylsulfides via Novel Synthetic Auxiliary Benzotriazole Promoted by Samarium Diiodide
Gen Liang LU , Yun Fa ZHENG , Yong Min ZHANG
1999, 10(9): 723-726
[Abstract](162) [FullText HTML] [PDF 124KB](0)
Aminomethyl arylsulfides are synthesized through nucleophilic substitution of a benzotriazolate anion by thiolates promoted by samarium diiodide.
Rearrangement of Hydrolysis Products of Tetrahydrofolate model compound
Jian Xin CHENI , Jun Sheng HAO , Wei GUO , Chi Zhong XIA
1999, 10(9): 727-728
[Abstract](157) [FullText HTML] [PDF 73KB](0)
The hydrolysis products of tetrahydrofolate model compound 4 were a mixture of 6 and 7 and the rearrangement reaction between 6 and 7 via 5 was in a state of equilibrium. confirmed by 1HNMR and IR spectra.
A New Reformatsky Type Reaction Via Cadmium Salt In Aqueous Media
Xiao Liang XU , Ping LU , Yong Min ZHANG
1999, 10(9): 729-730
[Abstract](161) [FullText HTML] [PDF 73KB](0)
In the presence of cadmium(Ⅱ) chloride-metallic samarium, α-bromoacetophenone reacts with aldehydes in THF-H20 under mild conditions to givep-hydroxy ketones in good yields.
Synthesis of Asymmetric 4H-1, 3, 2-Benzodioxaphosphorin 2-Sulfides from Intramolecular Cyclization Reaction
un Ran CHENG , Jia WEN , Rut Lian SHAO , Huan Yan CAO , Run Qiu HUANG
1999, 10(9): 731-732
[Abstract](161) [FullText HTML] [PDF 84KB](0)
Asymmetric 6-substituted-2-methoxy-4-(2,4-dichlorophenyl)-4H-1,3,2-benzodioxa-phosphorin 2-sulfides were prepared from intramolecular cyclization. The diastereomers were separated by column chromatography and fractional crystallization. Their structures were characterized on the basis of 1H NMR, 31P NMR and x-ray diffraction analysis.
Stereoselective Synthesis of (6R)-6-(5-Methyl-2-furyl)-2-oxocyclohexanecarboxyl-10', 2'-Sultam
Xi Lu WANG , You Hong HU , Li Gong OU , Dong Lu BAI
1999, 10(9): 733-734
[Abstract](157) [FullText HTML] [PDF 82KB](0)
Stereoselective synthesis of sultam 8 was reported. The overall yield in a sequence of 4 steps is 27.5%.
A New Chiral Synthesis of Naturally Occurring (-)-(S)-4-Hydroxy-2-pyrrolidinone
Pei Qiang HUANG , Xiao ZHENG , Shi Li WANG , Jian Liang YE , Li Ren JIN
1999, 10(9): 735-736
[Abstract](167) [FullText HTML] [PDF 68KB](0)
A new and convenient chiral synthesis of naturally occurring(-)-(S)-4-hydroxy-2-pyrrolidinone from (S)-malic acid was reported.
Synthesis of 9-(5-Pentyl-2-furyl)nonanoic Acid
1999, 10(9): 737-738
[Abstract](171) [FullText HTML] [PDF 79KB](1)
Naturally occurring 9-(5-pentyl-2-furyl) nonanoic acid which was synthesized through tive steps in about 20% overall yield by using 5-trimethylsilyl-2-furancarboxaldehyde as a starting material.
Synthesis of 1-[(O,O-diphenyl phosphonyl)arylmethyleneamino carbonylmethyl]uracils
Xue Jun LIU , Guo Chen CHI , Ru Yu CHEN
1999, 10(9): 739-740
[Abstract](172) [FullText HTML] [PDF 61KB](0)
A new series of compounds, 1-[(O,O-diphenyl phosphonyl)arylmethylene aminocarbo-nylmethyl]uracils, were synthesized in yield of 54.6-72.0% with DCC/BtOH as the coupling reagent, and their biological activities are being tested.
Synthesis and Properties of D-Thymidylyl (3'→5')L-Thymidine (D/L-TpT)
Xiao Hui GU , Yi Bing ZHANG , Yao Quan CHEN
1999, 10(9): 741-744
[Abstract](160) [FullText HTML] [PDF 130KB](0)
The synthesis and properties of D-thymidylyl (3'→5')L-thymidine (D/L-TpT) are described.
Formation and Photoelectrochemical Properties of Charge Transfer Complexes between Fullerene and Metallophthalocyanine
Zai Hong CHEN , Jun LIN , Juan LI , Hui ZHANG
1999, 10(9): 745-748
[Abstract](169) [FullText HTML] [PDF 134KB](0)
The formation of charge transfer complexes (CTC) between C60 with metallophthalocyanine (MPc. M=Zn. Co) has been investigated in three mixed organic solvents. fhe MPc-C60 CTC were characterized by using UV-Vis and fluorescence spectra. The formation eduilibrium constants (K) of CTC and their stoichiometry were determined. The foundation of CTC leads to a remarkable enhancement of the photoelectrochemical property. The CTC will provide a potential opportuniy to develop a new applicable photoelectric material.
Synthetic Studies of an Analogue of HIV-1 Protease Inhibitors of Didemnaketals:Construction of the C1-C8 Intermediate
Ping Zhen WANG , Yan Xing JIA , Yong Qiang TU , Bin WU
1999, 10(9): 749-750
[Abstract](170) [FullText HTML] [PDF 64KB](0)
A convenient and stercoselcctive approach to the synthesis of (3S. 4R, 6S)-2-oxo-3.4-dihvdrosy-6-methyl-octanatc derivative. a kcy intermediate for the synthesis of IIIV-1 protease inhibitor of didcmnaketals analogue, has been developed successfully from L-(-)-mcnthone.
Molecular Mechanics Study on Asymmetry Catalysis
Da Wei GUO , Xiao Zhen YANG
1999, 10(9): 751-754
[Abstract](159) [FullText HTML] [PDF 168KB](0)
A ground state model about an asymmetry hydrogenation of methyl pyruvate over Pl-nanocluster catalyst with a modifier cinconidine has been built. The role of the modifier in the catalytic process is explained.
Common Pharmacophore Model and 3D-QSAR Analysis of Two Different Tyrphostin Families
Ning LIAO , Ting Jun HOU , Jia Quan WANG , Chong Xi LI , Xiao Jie XU
1999, 10(9): 755-758
[Abstract](165) [FullText HTML] [PDF 159KB](0)
In the present study we investigated two groups of small molecular tyrosine kinase phosphorylation inhibitors (tyrphostins) with quite different structures(19 compounds of the bcnivlidenc maiononitrile famliy and 13 compounds of the 3-substituted indolin-2-ones family) With the aid of a pharmacophore analysis method (CATALYST). a common three-dimensional pharmacophore model to these two kinds of molecules has been discovered. A better 3D-QSAR analysis based on the generated pharmacophore model was conducted (correaate coeffcient R=0.9561 and the model shows very good predictive ability.
An Enhanced Comparative Molecular Field Analysis Method Using Genetic Algorithm
Ting Jun HOU , Ning LIAO , Hong Peng LUO , Xiao Jie XU
1999, 10(9): 759-762
[Abstract](174) [FullText HTML] [PDF 171KB](0)
In this study, an automated conformer selection procedure using genetic algorithm (GA) has been applied in comparative molecular field analysis (CoMPA) method. Using genetic algorithm, the 3D-QSAR model is optimized to an optimal one. From the calculation results, a group of QSAR models with high predictive ability can be obtained, which is superior than using conventional CoMFA; meamvhile, the active conlormers for these compounds in data set can he detcrmin cd from the best model.
Mass Spectral Behavior of Some Indole Schiff-Base Derivatives
Li XU , Shi Ping XU
1999, 10(9): 763-766
[Abstract](168) [FullText HTML] [PDF 101KB](0)
Twenty-two indole Schiff-base derivatives were synthesized. Two special ways of cleavage were discussed in the formation of the specific fragment ions in the mass spectra(MS).
Three New Triterpenoid Saponins from the Seeds of Aesculus chinensis
Jing ZHAO , Xiu Wei YANG , Yu Xin CU , Xue Hui LIU
1999, 10(9): 767-770
[Abstract](159) [FullText HTML] [PDF 111KB](0)
Three new triterpenoid saponins, escins IVc (1)IVd (2) and IVf (3) were isolated from the seeds of Aesculus chinensis. They were determined as 22α-tigloyl-28-acctylprotoaescigenin-3B-0-[B-D-glucopyranosyl (1→2)] [B-D-glucopyranosyl(1→4)]-B-D-glucopyranosiduronic acid 1.22a-angeloyl-28-acetylprotoaescigenin-3B-0-[B-D-glucopyranosyl (1→2)] [B-D-glucopyrano-sy((1→4)]-B-D-glucopyranosiduronic acid 2 and 28-tigloyl protoaescigenin-3B-0-[B-D-gluco-pyranosyl(12)] [B-D-glucopyranosyl(1→4)]-B-D-glucopyranosiduronic acid 3.
Paeonivayin, A New Monoterpene Glycoside from Paeonia delavayi
Yun Bao MA , Da Gang WU , Ji Kai LIU
1999, 10(9): 771-774
[Abstract](152) [FullText HTML] [PDF 114KB](0)
A new monotcrpcne glycoside named paeonivayin with other seven known compounds were isolated from the routs of Paeortio delavcrvi branch. and their structures were determined by means of spectroscopic studies
A New Oligostilbene from the Roots of Vitis Amurensis
Kai Sheng HUANG , Mao LIN , Lin Nine YU , Man KONG
1999, 10(9): 775-776
[Abstract](181) [FullText HTML] [PDF 74KB](1)
A new resveratrol trimer, amurensin G (1). was isolated from the roots of Vitis anznrensvs Rupr. Its structure and relative configuration were established on the basis of spectral evidence, especially on HMBC spectrum and NUT difference experiments.
Capillary Electrophoretic Separation of Proteins under the Control of Radial Electric Field
Yi CHEN , Ying ZHU
1999, 10(9): 777-780
[Abstract](155) [FullText HTML] [PDF 109KB](0)
Separation of basic proteins was performed using a homemade field-modulated capillary electrophoresis system. The resolution, elution and even wall adsorption can be regulated by adjusting the radial rather than axial voltage applied. Selection of running buffer and pH was found to be critical.
Effect of Caffeic acid on the Tumor Cells U937 Evaluated by an Electrochemical Voltammetric Method
Hong Yan JIAN , Cheng Cat AN , Jun FENG , Yun Xiang CI , Yi Li , Ayako SUGISAWA , Maremitsu IZUMITANI , Zhang Liang CHEN
1999, 10(9): 781-782
[Abstract](161) [FullText HTML] [PDF 99KB](0)
Electrochemical voltammctric method can be used to monitor cell health state during its growth. Here we studied the effect of caffeic acid on leukemia cells U937 by the voltammetric behavior of the cells. The result showed that this drug had a negative influence on cell health which suggests that caflcic acid may be used in inhibition oftumor cells
Synthesis and Characterization of Liquid Crystal with Lower Temperature of Phase Change of meso-tetra-(4-n-lauroyloxyphenyl)porphyrin
Wei LIU , Tong Shun SHI
1999, 10(9): 783-786
[Abstract](164) [FullText HTML] [PDF 203KB](0)
The synthesis and characterization of meso-tetra (4-n-lauroyloxy phenyl) porphyrin with long ester chains are reported. The domains of stability and the structure of the liquid crystalline phases are determined by optical microscopy and differential scanning calorimerials (DSC).
Copolymerization of N-4-Dibenzoylmethane Maleimide with Styrene
Qing Hui CHU , Meng Xian DING
1999, 10(9): 787-788
[Abstract](158) [FullText HTML] [PDF 83KB](0)
The copolymer of N-4-dibenzoylmethat}e maleimide (p-DBM1) with styrene (St) was prepared and characterized by gel permeation chromatography, thermal analysis and spectroscopy.
Preparation and Surfactant Properties of Amino Acid-based Surfactants
Qian CHEN , Steven F. CHEN , Zu Yi LI
1999, 10(9): 789-792
[Abstract](147) [FullText HTML] [PDF 124KB](0)
1-O-aminoacyl-3-O-alkyl acyl glycerols were synthesized by lipases in good yields and their surfactant properties were explored.
Ultrafast Optical Kerr Effect of ConjugatedSilver Phenylacetylide Complex Oligomer
Yi Hui XU , Li LIN , Jia Gang LUO , Boon K. TEO , Zong Ju XIA , Ying Hua ZOU , Hut Ying CHEN
1999, 10(9): 793-794
[Abstract](147) [FullText HTML] [PDF 98KB](1)
Silver phenylacetylide oligomer was found to exhibit prominent third-orde,nonlinear optical property. with susceptibility χ(3) of 2.4×10-4 esu (10-14 mol/L in 1:1 dimethyl sulfoxide/CHCl3 mixed solution) and second-order hyperpolarizability γ of 5.18×10-32 esu via heterodyned ultrafast optical Kerr et}feet measurement. It existed mainly as 1:1 complex oligomers and polymers as characterized by mass spectroscopy and elemental analysis etc.
Entanglement of Polymer Chains in Concentrated Region by Fluorescence Probe Technique
Xin Song LI , Guo Chang WANG , Bing Lin HE
1999, 10(9): 795-798
[Abstract](135) [FullText HTML] [PDF 155KB](0)
The fluorescence of polystyrene labeled with pyrenyl groups has been investigated in concentrated solutions.The ratio of excimer to monomer intensities (lc/1m) of pyrenyl labets is Found to vary with inereasing polymer concentration (C) and display fractional dependence on the C. A critical concentration, Cm at about 0.32g/ml, is first manifested. The results arc interpreted by interchain interaction and entanglement of polymer chains.
The Luminescence of The Phosphor Sr2ZrO4 with One-dimensional Chains Structure
Lei ZHANG , Guang Yan HONG , Xiao Lin SUN
1999, 10(9): 799-802
[Abstract](147) [FullText HTML] [PDF 104KB](0)
A new type of phosphor Sr2ZrO2 with one-dimensional structure was prepared by solid reaction and its luminescence is seen at room temperature. The excitation and emission spectra were measured and display broad maximum at 354 nm and 368 nm respectively. The mechanism of this luminescence is ascribed to charge transfer.
Effect of Metallic Additives on Structure and Catalytic Properties of Supported NiPB/SiO2 Catalyst
Ai Zeng MA , Wan Zhen LU , En Ze MIN
1999, 10(9): 803-806
[Abstract](133) [FullText HTML] [PDF 143KB](0)
A new preparation method was proposed to deposit amorphous alloys containing NiP and metallic additives such as Fe, Co. and Cu. The different effects of metallic additive on structure and catalytic properties of supported amorphous NiMPB/Si02 (M=Fe, Co. Cu) catalysts were observed. and the improvement of catalytic activity due to heating pretreatment in hydrogen was found.
The Site Symmetry of Eu3+ in ZnS:Eu Nanoparticle
Xiao Lin SUN , Gut Lan ZHANG , Guo Qing TANG , Wen Ju CHEN , Guang Yan HONG
1999, 10(9): 807-810
[Abstract](133) [FullText HTML] [PDF 125KB](0)
Nanosized ZnS doped with different concentrations of Eu3+ were prepared and analyzed by x-ray diffraction technique. The experimental results show that ZnS belongs to the cubic structure. From the photoluminescence (PL) emission spectra, it can be seen that the ratio of the emission intensity of Eu3+ at 616 nm to that at 590 nm increases as the increasing of Eu3+. This phenomenon reveals that the site symmetry of Eu3+ reduces as the increasing of Eu3+.
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