2001 Volume 12 Issue 7

A Rapid and Convenient Synthesis of Acylals from Aldehydes and Acetic Anhydrides Catalyzed by SnCl4/SiO2
Yi Qun LI , Li Hui CHENG
2001, 12(7): 565-568
[Abstract](195) [FullText HTML] [PDF 27KB](1)
A variety of aldehydes were converted into acylals in excellent ields with acetic anhydride in the presence of a catalytic amount of tin (Ⅳ) chloride supported on silica gel at room temperature.
Synthesis of a New β-Mercaptoalcohol
Jian Feng GE , Li Fen ZHANG , Zong Xuan SHEN , Ya Wen ZHANG
2001, 12(7): 569-570
[Abstract](209) [FullText HTML] [PDF 25KB](0)
In this letter, (R)-1,1-diphenyl-2-mercapto-3-methyl-1-butanol was synthesized from L-valinc and two synthetic routes have been tried.
Synthesis of Optical Active 2-Arylpropionic Acids
Bo WANG , Hong Zhu MA , Qi Zhen SHI
2001, 12(7): 571-574
[Abstract](184) [FullText HTML] [PDF 29KB](0)
(S)-2-(6'-methoxyl-α-naphthyl) propionic acid ((S)-Naproxen, ee 99%) has been prepared starting from (6-methoxyl-α-naphthyl)propan-1-one and D-sorbitol under SmCl3catalysis.
Stereoselective Synthesis of N1-Lyxitol Inosine Derivative
Li Jun HUANG , Yan PANG , Ji Mei MIN , Li He ZHANG
2001, 12(7): 575-578
[Abstract](192) [FullText HTML] [PDF 53KB](1)
1,4-anhydro-2-triflyl-3,5-O-benzenylidene-L-xylitol (5) was constructed in six steps from protected D-xylose. Substitution of 5 with protected 8-bromoinosine 6 gave the key intermediate 5'-O-TBS-2',3'-di-O-acetyl-N1-(2"-deoxy-1",4"-anhydro-3",5"-O-benzenylidene-Llyxitol-2"-yl)-8-bromoinosine (14). Selective removal of 5'-O-TBS-group gave the corresponding 5'-O-phosphorodianilidate 4 though phosphorylation, which was characterized by X-ray crystallographic analysis.
An Improved Synthesis of trans-3, 3b, 4, 9b, 10, 11-Hexahydro-6-methoxy-9b-methyl-7-(1-methylethyl) phenanthro {1,2-c[furan-1,5-dione]}
Xue Qiang YIN , Guang Zhong YANG , Yuan Chao LI
2001, 12(7): 579-580
[Abstract](196) [FullText HTML] [PDF 24KB](3)
trans-3, 3b, 4, 9b, 10, ll-Hexahydro-6-methoxy-9b-methyl-7-(l-methylethyl) phenanthro {1,2-c[furan-l,5-dione]} was synthesized with good yield in two steps from triptophenolide methyl ether under mild conditions.
Facial Selectivity in the Nucleophilic Additions of endo-Tricyclo [5.2.1.O2.6]deca-2 (6),8-dien-3-one
2001, 12(7): 581-584
[Abstract](216) [FullText HTML] [PDF 36KB](1)
Nucleophilic additions to endo-tricyclo []deca-2(6),8-dien-3-one 4 are described.Experimental results show high preference for exo-facial attack to the enone moiety of tricyclodecadienone. Steric hindrance is the main kinetically controlling factor in the nucleophilic reaction. The shielding effect and the stabilizing effect of the norbornene double bond favor the exo-facial attack also.
Study on Nucleophilic Additions to endo-tricyclo [5.2.1.O2.6]deca-2 (6),8-dien-3-one and an Unusual Payne Rearrangementof α, β-Epoxy Tricyclodecenone
2001, 12(7): 585-588
[Abstract](188) [FullText HTML] [PDF 37KB](0)
Synthesis of highly strained tetracyclic ketones was achieved by cyclopropanation or epoxidation of tricyclodecenone 1. An unusual formation of α-methoxy β-hydroxy ketone from an α,β-unsaturated enone system via Payne rearrangement was reported.
Study on the Synthesis and Biodegradation of Aliphatic Polyester
Chang Ying ZHU , Xiao Di KOU , Zhi Qiang ZHANG , Ying Cai YOU , Diao Hu Xin
2001, 12(7): 589-592
[Abstract](204) [FullText HTML] [PDF 28KB](0)
An aliphatic polyester, poly(hexalene adipate) (PHA) and an aliphatic copolyester, poly (hexalene adipate succinate) (PHAS) were synthesized by direct condensation of corresponding binary acid and binary alcohol in the presence of a catalyst, p-toluene sulfonic acid. The biodegradation of these polyesters were studied in the laboratory by enzyme attack and outdoor soil burial. The results show that these polyesters have good biodegradability and the copolyester PHAS, even displayed a better biodegradability than the polyester PHA. In the presence of Penicillium chrysogenum the weight loss reached 18.3% for the PHAS (film thickness 1.0 mm)and 9.1% for the PHA (film thickness 1.0 mm) after 28 days. Outdoor soil burial tests indicate that these polyesters also have good biodegradability in natural conditions. The weight loss reached 14.2% for PHAS (film thickness 0.1 mm) and 6.7% for PHA (film thickness 0.1mm) after burying in soil for 36 days.
Synthesis and Characterization of Poly (ether imide)s Containing Phthalazinone and Isopropyl Moieties
Jin Yan WANG , Xi Gao JIAN , Shu De XIAO
2001, 12(7): 593-594
[Abstract](193) [FullText HTML] [PDF 22KB](0)
A novel poly (ether imide)s containing phthalazinone and isopropyl moieties derived from 2-(4-aminophenyl)-4-[4-(4-aminophenoxy) phenyl]-phthalazin-l-one and bisphenol-A diphthalic anhydride was synthesized by one-step solution condensation polymerization in m-cresol. The polymer was characterized by FTIR, NMR, molecular weights, glass transition temperature,thermal degradation temperature and WAXD.
Synthesis of Dendritic-Linear Block Copolymers by Atom Transfer Radical Polymerization
You Liang ZHAO , Ai Jun GONG , Jing JIANG , Hong Wei LIU , Chuan Fu CHEN , Fu XI
2001, 12(7): 595-596
[Abstract](184) [FullText HTML] [PDF 20KB](0)
The dendritic polyarylether 2-bromoisobutyrate as the macromolecular initiator for the controlled free radical polymerization of styrene was investigated. The polymerization was carried out with CuBr/2,2'-bipyridine catalyst at 110℃. It is found that the hybrid dendritic-linear block copolymers possess well-defined molecular weights and low polydispersities.
A New Eudesmanolide and a New Aromatic Derivative from Carpesium cernuun
Chao YANG , Qi Xiu ZHU , Wei YONG , Zhong Jian JIA
2001, 12(7): 598-600
[Abstract](190) [FullText HTML] [PDF 33KB](1)
A new eudesmanolide and a new aromatic derivative were isolated from the roots of Carpesium cernuun. Their structures were elucidated as 13-hydroxy-5,7(11)-eudesmadien-12,8-olide and 3-methyl-8-acetoxy-9,10-diisobutyryloxy-p-cymene by spectral methods (EIMS, FAB-MS, 1D and 2D NMR).
Two New Eremophilane Sesquiterpenes from Cacalia ainsliaeflora
Man Jun MAO , Zhong Jian JIA
2001, 12(7): 601-602
[Abstract](193) [FullText HTML] [PDF 23KB](0)
Two new eremophilane sesquiterpenes 33-angeloyloxy-8α-hydroxy-6β-methoxy eremophil-7 (11), 9 (10)-dien-8, 12-olide (1) and 3β-angeloyloxy-6β, 8α-dihydroxy-eremophi-7(11), 9 (10)-dien-8, 12-olide (2) were isolated from Cacalia ainsliaeflora. Their structures were established by spectroscopic methods and 2D NMR experiments.
Three New Coumarins from Micromelum integerrimum
Hong Ping HE , Yun ZOU , Yue Mao SHEN , Xiao Yan HAO , Guo Yin ZUO , Xiao Jiang HAO
2001, 12(7): 603-606
[Abstract](198) [FullText HTML] [PDF 36KB](1)
Three derivatives of micromelin, named hydramicromelins A-C (1-3), were isolated from the aerial part of Micromelum integerrimum (Buch.-Ham) Roem., respectively.Hydramicromelins A-C (1-3) were epimers which possessed the same plane structure and molecular formula. Their structures were elucidated based on MS and NMR data. The relative configurations of 1-3 were established by NOE analysis.
Leiocyclocin A and B, Two Cyclopeptides from Goniothalamus leiocarpus
Qing MU , Rong Wei TENG , Chao Ming LI , De Zu WANG , Yu WU , Han Dong SUN , Chang Qi HU
2001, 12(7): 607-610
[Abstract](193) [FullText HTML] [PDF 38KB](0)
Two new cyclopeptides, leiocyclocin A (1), B (2), were isolated from the seeds of Goniothalamus leiocarpus. Their structures were elucidated by means of spectral and chemical methods.
Gnetupendin C, a New Stilbene Dimer from the Lianas of Gnetum Pendulum
Xiao Mei LI , Ying Hong WANG , Mao LIN
2001, 12(7): 611-612
[Abstract](220) [FullText HTML] [PDF 34KB](1)
Gnetupendin C, a new dimer coupled by a resveratrol and an oxyresveratrol unit, was isolated from the lianas of Gnetum pendulum C.Y. Cheng (Gnetaceae). Its structure was established on the basis of spectroscopic evidence, especially 2D techniques.
A New Spirostanol Saponin from Dioscorea futshauensis
Hong Wei LIU , Hisayoshi KOBAYASHI , Ge Xia QU , Xin Sheng YAO
2001, 12(7): 613-616
[Abstract](189) [FullText HTML] [PDF 32KB](0)
A new spirostanol saponin presenting strong activity of inducing morphological deformation of Pyricularia oryzae mycelia was isolated from Dioscorea futshauensis R. Kunth by bioactivity-guided fractionation. The structure was established as (25S)-spirost-5-en-3β,27-diol-3-O-[α-L-rhamnopyranosyl (1→2)-β-D -glucopyranosyl (l→3)]-β-D-glucopyranoside on the basis of chemical evidences and spectral analysis, especially by 2D-NMR techniques.
A New Benzosesquiterpenoid Dimer from Polyalthia cheliensis Hu
Wei Ming ZHU , Xin HONG , Yue Mao SHEN , Bi Tao ZHAO , Hong Ping HE , Xiao Jiang HAO
2001, 12(7): 617-618
[Abstract](202) [FullText HTML] [PDF 24KB](2)
A new benzosesquiterpenoid dimer, 3",3"'-bispolycerasoidol (1), along with its monomer, polycerasoidol, were isolated from the dried leaves of Polyalthia cheliensis Hu. The structure of 1 was established by spectroscopic methods.
Intercalation of Epinephrine with Calf-thymus ds-DNA
Sai Jing ZHENG Xiang Qin LIN
2001, 12(7): 619-622
[Abstract](200) [FullText HTML] [PDF 40KB](0)
A strong interaction between double stranded calf-thymus DNA (ds-DNA) and epinephrine but no interaction between single stranded calf-thymus DNA (ss-DNA) and epinephrine were observed by the use of UV-spectroscopy and cyclic voltammetry. It is suggested that the interaction leads to an intercalation of EP molecules into the groove of ds-DNA and the formation of ds-DNA(EP)n complex.
Study of Oxidation of Glutathione Treated with Hypochlorous Acid by Capillary Electrophoresis
Xian LUO , Jian De LU , Xiao Yun FU
2001, 12(7): 623-624
[Abstract](187) [FullText HTML] [PDF 22KB](0)
Capillary electrophoresis (CE) method was developed for the separation and quantification of reduced glutathione (GSH), oxidized glutathione (GSSG) and glutathione sulphonic acid (GSO3H). Baseline separation was obtained within five minutes. The effects of reaction time and molar ratio of hypochlorous acid (HOCI) to GSH on the oxidation of GSH were investigated.
A Hydrogen Peroxide Biosensor Combined HRP Doped Polypyrrole with Ferrocene Modified Sol-gel Derived Composite Carbon Electrode
Fa Ming TIAN , Bo XU , Guo Yi ZHU
2001, 12(7): 625-728
[Abstract](192) [FullText HTML] [PDF 34KB](1)
A novel amperometric biosensor for the detection of hydrogen peroxide is described.The biosensor was constructed by electrodepositing HRP/PPy membrane on the surface of ferrocenecarboxylic acid mediated sol-gel derived composite carbon electrode. The biosensor gives response to hydrogen peroxide in a few seconds with detection limit of 5×l0-7 mol · L-1 (based on signal:noise=3). Linear range is up to 0.2 mmol · L-1.
Direct Electrochemistry of Hemoglobin in Layer-by-layer {PDDA/Hb}n Films Assembled on Pyrolytic Graphite Electrodes
Ping Li HE , Nai Fei HU
2001, 12(7): 629-630
[Abstract](194) [FullText HTML] [PDF 26KB](0)
Layer-by-layer {PDDA/Hb}n films were assembled by means of alternate adsorption of positively charged poly (diallyldimethyl ammonium) (PDDA) and negatively charged hemoglobin (Hb) at pH 9.2 from their aqueous solutions on pyrolytic graphite (PG) electrodes. Film growth during adsorption cycles was demonstrated by cyclic voltammetry and UV-Vis spectroscopy.Direct electrochemistry of Hb in {PDDA/Hb}n films on PG was studied.
Two-photon Pumped Up-conversion Lasing Properties of A Series of Organic Salts with Different Side-chains
Yu Peng TIAN , Fu Ying HAO , Jie Ying WU , Qi FANG , Min Hua JIANG
2001, 12(7): 631-634
[Abstract](188) [FullText HTML] [PDF 30KB](0)
The synthesis and upconverted fluorescent properties of a series of organic compounds with the structure:donor/bridge/acceptor, and different side-chains are reported. The results show that the compounds with different side-chains exhibit different two-photon induced fluorescent properties, although they have the same main donor/bridge/acceptor structure.
Spectrophotometric Determination of Trace Chromium (Ⅵ)in Mass Chromium (Ⅲ)
Zi Gang XU , Xian Hong WEN , Qing Zhou WU
2001, 12(7): 631-634
[Abstract](176) [FullText HTML] [PDF 18KB](0)
The method for the sepration and determination of trace Cr(VI) exiting in mass Cr(Ⅲ) has been researched. The method is highly sensitive and less interference, but is simple and useful for analysis trace Cr(VI).
Theoretical Studies on the Conformation of mono-6-O-p-nitrobenzoyl-β-cyclodextrin in Aqueous Solution
Yong FENG , Hai Ming ZHANG , Lei LIU , Yong Hui WANG , Zhao Xiong LIANG , Qing Xiang GUO
2001, 12(7): 637-640
[Abstract](203) [FullText HTML] [PDF 68KB](0)
The conformation of mono-6-O-p-nitrobenzoyl-β-cyclodextrin was studied with B3LYP/6-311g**//PM3 calculations in vacuum and in water solution. It was concluded that the p-nitrobenzoyl group of the molecule should be located above the primary hydroxyls of the cyclodextrin instead of being completely enclosed by the cavity. It was proposed that the behavior might be caused by the requirement of a cis ester bond in the self-included conformation of the molecule.
Kinetic Model of Hypophosphite Oxidation on a Nickel Electrode in D2O Solution
Yue ZENG , Hui Xian WANG , Shang Ci YU , Xin De WU , Xue Qiang CAO
2001, 12(7): 641-644
[Abstract](191) [FullText HTML] [PDF 78KB](0)
Kinetic model of hypophosphite oxidation on a nickel electrode was studied in D2Osolution in order to reach a better understanding of the oxidation mechanism. In the model the electrooxidation of hypophosphite undergo a H abstraction of hypophosphite from the P-H bond to form the phosphorus-centered radical PHO2-, which subsequently is electrochemically reacted with water to form the final product, phosphite. The kinetic equations were derived, and the kinetic parameters were obtained from a comparison of experimental results and the kinetic equations. The process of hypophosphite electrooxidation could be well simulated by this model
Study of the Electrical Double Layer of a Spherical Micelle:Functional Theoretical Approach
Zheng Wu WANG , Gan Zuo LI , Da Ren GUAN , Xi Zhang YI , An Jing LOU
2001, 12(7): 645-646
[Abstract](205) [FullText HTML] [PDF 26KB](0)
By using the iterative method in functional theory, an analytic expression of the Poisson-Boltzmann equation (PB eq.), which describes the distribution of the potential of electrical double layer of a spherical micelle, has been carried out under the general potential condition for the first time. The method also can give the radius, the surface potential, and the thickness of the layer.
Influence of Geometric Structure of Immobilized Aluminium Chloride Catalyst on Catalytic Property in Isobutene Polymerization
Tian Xi CAI , Min HE , Xian Zhe SHI , Xin Ping WANG
2001, 12(7): 647-650
[Abstract](189) [FullText HTML] [PDF 37KB](0)
The catalytic property of AlCl3 catalyst immobilized on γ-Al2O3 for isobutene polymerization has been studied. It was found that the activity, selectivity and stability of the catalyst are dependent greatly on geometric characteristic of the pore structure and size of catalyst.Although the activity and selectivity of the catalysts with micro-and meso-pore structure are all high in initial stage, but their stability is low, while those with bimodal meso-and macro-pore structure are excellent. Increasing granularity of the catalyst (particle become fine) brings about an increase in isobutene conversion, but a decrease in selectivity, resulting in lower average molecular weight and its broader distribution.
Synthesis, Characterization and Luminescence of Lanthanide Chloride Complexes with N,N,N',N'-Tetra [(2-benzimidazolyl) methyl]-l,2-Ethanediamine
Ming Jie ZHANG , Ling HUANG , Xiu Fang SHI , De Qing GAO , Song Lin LI , Gui Mei CAI , Yan Yi HUANG , Guang Qing YAO , Jing LI
2001, 12(7): 651-654
[Abstract](183) [FullText HTML] [PDF 43KB](0)
N,N,N',N'-tetra [(2-benzimidazolyl) methyl]-l,2-ethanediamine (EDTB) lanthanidechloride complexes were prepared (Ln3+=Eu3+, Tb3+or Gd3+). The results of single crystal X-ray structural analysis show that [(EDTB) GdCl2]Cl(C2H5OH)(H2O)2 crystal is in space group P21/c with a=8.848(2) Å, b=26.313(5) Å, c=18.929(4) Å, β=97.82 (3)°, V=4366(2) Å3, Z=4. The luminescent properties of the terbium and europium complexes have been studied.
The Nature of Bonding in WC and WN
Xue Mei GAO , Shi Xi LIU , Xiao Guang XIE , Huai CAO , Shu Shan DAI
2001, 12(7): 655-658
[Abstract](191) [FullText HTML] [PDF 30KB](3)
The nature of bonding in the title compounds has been studied by using CASSCF and FOCl techniques. The ground states of WC and WN are found to be 3Δ and 4- state arising primarily from:...1σ2σ21π411 and...1σ2σ2421 configuration respectively. WC shows a strong character of covalent bond while WN have obvious character of ionic bond and the dissociation energy of WN is larger than that of WC (6.15 and 5.41 eV respective).
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