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2002 Volume 13 Issue 5
2002, 13(5): 393-395
Abstract:
Aseries of tetrahydrobenzo-[b]-pyran derivative was synthesized by the reaction of arylmethylene malononitrile or arylmethylene cyanoacetate with dimedone in ethylene glycol at 80℃ without catalyst. The structures of the two products were characterized by X-ray diffraction.
Aseries of tetrahydrobenzo-[b]-pyran derivative was synthesized by the reaction of arylmethylene malononitrile or arylmethylene cyanoacetate with dimedone in ethylene glycol at 80℃ without catalyst. The structures of the two products were characterized by X-ray diffraction.
2002, 13(5): 396-397
Abstract:
Allylic acetates were reduced with Pd(0)-SmI2 in the presence of ArSeBr to form corresponding allylic selenides in good yields.
Allylic acetates were reduced with Pd(0)-SmI2 in the presence of ArSeBr to form corresponding allylic selenides in good yields.
2002, 13(5): 398-401
Abstract:
For the first time the isomerization of 1, 3, 2-diazaphospholidine-2-selenide derivatives in refluxing benzene in the presence of trace water was observed. The structures of isomerized products were determined by IR, 1H NMR, 31P NMR, elemental analysis and X-ray crystallography. The mechanism of isomerization was also proposed.
For the first time the isomerization of 1, 3, 2-diazaphospholidine-2-selenide derivatives in refluxing benzene in the presence of trace water was observed. The structures of isomerized products were determined by IR, 1H NMR, 31P NMR, elemental analysis and X-ray crystallography. The mechanism of isomerization was also proposed.
2002, 13(5): 402-404
Abstract:
Bcnzotriazolc, aldehydes and primary selenoamides read together with elimination of water to form 1:1:1 adducts which arc rcduccd smoothly by NaBH4 to give the N-substituted selenoamides in good yield.
Bcnzotriazolc, aldehydes and primary selenoamides read together with elimination of water to form 1:1:1 adducts which arc rcduccd smoothly by NaBH4 to give the N-substituted selenoamides in good yield.
2002, 13(5): 405-406
Abstract:
Funclionalizcd bcnzylic zinc halides rcactcd with bcnzaldehydcs in the prcscncc of Lewis acid Mc3SiCl giving high yields of trans-vstilbcncs under the catalysis of Co(PPh3)3Cl.
Funclionalizcd bcnzylic zinc halides rcactcd with bcnzaldehydcs in the prcscncc of Lewis acid Mc3SiCl giving high yields of trans-vstilbcncs under the catalysis of Co(PPh3)3Cl.
2002, 13(5): 407-409
Abstract:
2'-Benzoxazolyl substituted cyclopropane derivatives were synthesized in the yield of 73-89% from the reaction of telluronium ylides with chalcones.
2'-Benzoxazolyl substituted cyclopropane derivatives were synthesized in the yield of 73-89% from the reaction of telluronium ylides with chalcones.
2002, 13(5): 410-411
Abstract:
A novel synthesis of polyfluoroalkyl substituted γ-butyrolactones from the reaction of polyfluoroalkyl iodides with 4-pentenoic acid initiated with sodium dithionite was realized in good yields.
A novel synthesis of polyfluoroalkyl substituted γ-butyrolactones from the reaction of polyfluoroalkyl iodides with 4-pentenoic acid initiated with sodium dithionite was realized in good yields.
2002, 13(5): 412-415
Abstract:
A series of 3-methoxycarbonylpropoxy-7-(imidazol-4-ylpropinamide)-1, 3-dihydrogen-1-methyl-5-phenyl-2H-1, 4-benzodiazepin-2-ones, as farnesyltransferase(Ftase) inhibitors, were synthesized. The preparation of the key intermediate, 7-amino-3-methoxycabonylpropoxy-1- methyl-5-phenyl-2H-1,4-benzodiazepin-2-one, was improved.
A series of 3-methoxycarbonylpropoxy-7-(imidazol-4-ylpropinamide)-1, 3-dihydrogen-1-methyl-5-phenyl-2H-1, 4-benzodiazepin-2-ones, as farnesyltransferase(Ftase) inhibitors, were synthesized. The preparation of the key intermediate, 7-amino-3-methoxycabonylpropoxy-1- methyl-5-phenyl-2H-1,4-benzodiazepin-2-one, was improved.
2002, 13(5): 416-419
Abstract:
Transesterification reaction of lactose with divinyladipate in pyridine catalyzed by an alkaline protease from Bacillus subtilis at 50℃ for 3 days gave 6'-O-vinyladipoyl-lactose (yield 35%). Poly(6'-O-vinyladipoyl-lactose) with Mn=21,200, Mw=32,900, Mw/Mn=1.56 could be obtained by chemical polymerization. Poly(vinyl alcohol) containing lactose branch was biodegradable. After 6 days in aqueous buffer (PH 7), this alkaline protease could degrade the polymer to an Mn of ca. 2100, Mw/Mn=2.56.
Transesterification reaction of lactose with divinyladipate in pyridine catalyzed by an alkaline protease from Bacillus subtilis at 50℃ for 3 days gave 6'-O-vinyladipoyl-lactose (yield 35%). Poly(6'-O-vinyladipoyl-lactose) with Mn=21,200, Mw=32,900, Mw/Mn=1.56 could be obtained by chemical polymerization. Poly(vinyl alcohol) containing lactose branch was biodegradable. After 6 days in aqueous buffer (PH 7), this alkaline protease could degrade the polymer to an Mn of ca. 2100, Mw/Mn=2.56.
2002, 13(5): 420-421
Abstract:
By using OH-terminated polyarylether dendrimer and N-Fmoc-glycine as raw materials, the dendritic polyarylether 2-aminoacetate (G3-NH2) was synthesized via two step reactions. G3-NH2 as a macroinitiator for the ring-opening polymerization of γ-benzyl L-glutamate N-carboxyanhydride was investigated. It is found that the resulting copolymers possessed relatively high molecular weight and narrow molecular weight distribution (1.12< Mw/Mn<1.28).
By using OH-terminated polyarylether dendrimer and N-Fmoc-glycine as raw materials, the dendritic polyarylether 2-aminoacetate (G3-NH2) was synthesized via two step reactions. G3-NH2 as a macroinitiator for the ring-opening polymerization of γ-benzyl L-glutamate N-carboxyanhydride was investigated. It is found that the resulting copolymers possessed relatively high molecular weight and narrow molecular weight distribution (1.12< Mw/Mn<1.28).
2002, 13(5): 422-425
Abstract:
A novel bipolar conjugated polymer containing triphenylamine and 1, 3, 4-oxadiazole units was synthesized by Suzuki reaction. Its structure and properties were characterized by NMR, IR, UV-Vis, PL spectroscopy and electrochemical measurement. The photoluminescent spectroscopy and cyclic voltammograms measurement demonstrated that the resulting polymer shows blue emission (477 nm) and possesses both electron and hole-transporting property
A novel bipolar conjugated polymer containing triphenylamine and 1, 3, 4-oxadiazole units was synthesized by Suzuki reaction. Its structure and properties were characterized by NMR, IR, UV-Vis, PL spectroscopy and electrochemical measurement. The photoluminescent spectroscopy and cyclic voltammograms measurement demonstrated that the resulting polymer shows blue emission (477 nm) and possesses both electron and hole-transporting property
2002, 13(5): 426-427
Abstract:
A new benzylisoquinoline alkaloid, 1, 2, 3, 4-tetrahydro-5-hydroxyl-8-methoxyl-2- methyl-4'-methoxyl-benzylisoquinoline, was isolated from the arial parts of Sabia parviflora. Its structure was established on the basis of spectral analysis.
A new benzylisoquinoline alkaloid, 1, 2, 3, 4-tetrahydro-5-hydroxyl-8-methoxyl-2- methyl-4'-methoxyl-benzylisoquinoline, was isolated from the arial parts of Sabia parviflora. Its structure was established on the basis of spectral analysis.
2002, 13(5): 428-429
Abstract:
A new flavone, 6, 2'-dihydroxy-5, 7, 8, 6'-tetramethoxyflavone, was isolated from the roots of Scutellaria baicalensis. Its structure was established on the basis of spectral evidences.
A new flavone, 6, 2'-dihydroxy-5, 7, 8, 6'-tetramethoxyflavone, was isolated from the roots of Scutellaria baicalensis. Its structure was established on the basis of spectral evidences.
2002, 13(5): 430-431
Abstract:
A new monoterpene glycoside, acetoxypaeoniflorin, was isolated from the root cortex of Paeonia veitchii Lynch.. The structure was elucidated by spectral methods.
A new monoterpene glycoside, acetoxypaeoniflorin, was isolated from the root cortex of Paeonia veitchii Lynch.. The structure was elucidated by spectral methods.
2002, 13(5): 432-435
Abstract:
Two new acyclic diterpene-γ-lactones named hanliuine Ⅲ (1) and hanliuine Ⅳ (2) were isolated from leaves of Salix matsudana(Chinese name "hanliu"). Their structures were deduced from spectral data.
Two new acyclic diterpene-γ-lactones named hanliuine Ⅲ (1) and hanliuine Ⅳ (2) were isolated from leaves of Salix matsudana(Chinese name "hanliu"). Their structures were deduced from spectral data.
2002, 13(5): 436-439
Abstract:
Functional Ni2+-polyacrylic acid (Ni2+-PAA) adsorbent has been prepared for metal chelate affinity chromatography. DNA elements coding for adjacent histidines were fused to the Aeromonas hydrophila ompTS gene. Subsequent expression in E. coli resulted in the production of hybrid protein 6His-OmpTS that could be purified by Ni2+-PAA affinity chromatography.
Functional Ni2+-polyacrylic acid (Ni2+-PAA) adsorbent has been prepared for metal chelate affinity chromatography. DNA elements coding for adjacent histidines were fused to the Aeromonas hydrophila ompTS gene. Subsequent expression in E. coli resulted in the production of hybrid protein 6His-OmpTS that could be purified by Ni2+-PAA affinity chromatography.
2002, 13(5): 440-441
Abstract:
A new method of determination for roxithromycin tablets by non-aqueous capillary electrophoresis (NACE) with square-wave amperometric detection was carried out. Several parameters affecting the NACE-AD determination were studied. The data was modified by spline wavelet least square (SWLS). The method is simple, rapid and highly reliable for routine analysis.
A new method of determination for roxithromycin tablets by non-aqueous capillary electrophoresis (NACE) with square-wave amperometric detection was carried out. Several parameters affecting the NACE-AD determination were studied. The data was modified by spline wavelet least square (SWLS). The method is simple, rapid and highly reliable for routine analysis.
2002, 13(5): 442-443
Abstract:
The standard association constants of ionic pair [GaCl]2+, Kas, were determined by emf(electromotive force) method at 278.15 to 318.15 K. The thermodynamic quantities for the ionic association process were calculated and it was pointed that the association entropy is driving force to form the ionic pair.
The standard association constants of ionic pair [GaCl]2+, Kas, were determined by emf(electromotive force) method at 278.15 to 318.15 K. The thermodynamic quantities for the ionic association process were calculated and it was pointed that the association entropy is driving force to form the ionic pair.
2002, 13(5): 444-447
Abstract:
Based on cryogenic FT-IR spectroscopic studies of hydrogen bonds in cholic acid, two-dimensional FT-IR spectroscopy was applied to enhance our understanding of the hydrogen bonds of cholic acid. Fine spectral structures were revealed by asynchronous 2D FT-IR spectra. The co-relationship among various bands was discussed according to the synchronous 2D FT-IR spectrum.
Based on cryogenic FT-IR spectroscopic studies of hydrogen bonds in cholic acid, two-dimensional FT-IR spectroscopy was applied to enhance our understanding of the hydrogen bonds of cholic acid. Fine spectral structures were revealed by asynchronous 2D FT-IR spectra. The co-relationship among various bands was discussed according to the synchronous 2D FT-IR spectrum.
2002, 13(5): 448-451
Abstract:
Dynamic behaviors on polyacrylic acid (PAA) gels and mass (small molecules) transports in the gels have been studied mainly by dynamic light scattering (DLS). The cross-linking degree (fc), monomer concentration (Cm) and temperature of the gels have significant influences on its dynamic behavior and mass transport in the gels. The increase of fc leads to decrease of the mesh sizes of the gels, thus the obstacle of the gels for mass transport is increased. As a result, small molecular diffusion Dk in the gels is decreased. So even if for small molecules, the Dk also is influenced.
Dynamic behaviors on polyacrylic acid (PAA) gels and mass (small molecules) transports in the gels have been studied mainly by dynamic light scattering (DLS). The cross-linking degree (fc), monomer concentration (Cm) and temperature of the gels have significant influences on its dynamic behavior and mass transport in the gels. The increase of fc leads to decrease of the mesh sizes of the gels, thus the obstacle of the gels for mass transport is increased. As a result, small molecular diffusion Dk in the gels is decreased. So even if for small molecules, the Dk also is influenced.
2002, 13(5): 452-455
Abstract:
Three dye-doped polymer rods in different matrices were synthesized in which weak hydrogen bond, strong hydrogen bond and covalent bond existed between the dye and the polymer chain. And the two-photon up-conversion luminescent properties of HMASPS and HEASPS1
Three dye-doped polymer rods in different matrices were synthesized in which weak hydrogen bond, strong hydrogen bond and covalent bond existed between the dye and the polymer chain. And the two-photon up-conversion luminescent properties of HMASPS and HEASPS1
2002, 13(5): 456-459
Abstract:
The effects of thermal history on the rheological properties of partially hydrolyzed polyacrylamide/sodium dodecyl sulfate complex aqueous solutions have been studied using both steady shear and dynamic temperature sweep characterizations. An abnormal rheological behavior was found that dynamic moduli of the aqueous solutions increased, while the viscosity decreased after thermal treatment, which could help to gain insight into the micro-phase evolution of the polymer/surfactant complex aqueous solutions and its dependence on temperature.
The effects of thermal history on the rheological properties of partially hydrolyzed polyacrylamide/sodium dodecyl sulfate complex aqueous solutions have been studied using both steady shear and dynamic temperature sweep characterizations. An abnormal rheological behavior was found that dynamic moduli of the aqueous solutions increased, while the viscosity decreased after thermal treatment, which could help to gain insight into the micro-phase evolution of the polymer/surfactant complex aqueous solutions and its dependence on temperature.
2002, 13(5): 460-463
Abstract:
A novel photochromic complex comprising of Keggin type tungstophosphate acid (PW12) and polyacrylamide (PAM) was prepared. FT-IR results showed that the Keggin geometry of PW12 was still preserved inside the composite, and a charge-transfer bridge was built between PW12 and PAM via hydrogen bond. AFM images indicated that surface topography of polymer matrix changed after adding PW12. Under UV irradiation, the film was reduced photochemically to yield a blue species, which was reversible in the present of oxygen in polymeric network.
A novel photochromic complex comprising of Keggin type tungstophosphate acid (PW12) and polyacrylamide (PAM) was prepared. FT-IR results showed that the Keggin geometry of PW12 was still preserved inside the composite, and a charge-transfer bridge was built between PW12 and PAM via hydrogen bond. AFM images indicated that surface topography of polymer matrix changed after adding PW12. Under UV irradiation, the film was reduced photochemically to yield a blue species, which was reversible in the present of oxygen in polymeric network.
2002, 13(5): 464-467
Abstract:
A transparent thin film was prepared by depositing the sol-gel mixture for the synthesis of MCM-41 mesoporous molecular sieve doped with rhodamine 6G (R6G) dye on glass substrates. The film of silica-surfactant-R6G materials, which was identified to possess hexagonally ordered mesostructure, was composed of nanocrystallites about 35 nm in diameter and 1-10(m in thickness. Cleanness of the substrates, concentration of the sol-gel mixture and rate of evaporation of the solvent were the key factors affecting transparency and homogeneity of the film. Moreover, optical change and lack in dye aggregation were observed to the R6G-functionalized MCM-41 thin film in contrast with that in ethanol solution.
A transparent thin film was prepared by depositing the sol-gel mixture for the synthesis of MCM-41 mesoporous molecular sieve doped with rhodamine 6G (R6G) dye on glass substrates. The film of silica-surfactant-R6G materials, which was identified to possess hexagonally ordered mesostructure, was composed of nanocrystallites about 35 nm in diameter and 1-10(m in thickness. Cleanness of the substrates, concentration of the sol-gel mixture and rate of evaporation of the solvent were the key factors affecting transparency and homogeneity of the film. Moreover, optical change and lack in dye aggregation were observed to the R6G-functionalized MCM-41 thin film in contrast with that in ethanol solution.
2002, 13(5): 468-471
Abstract:
Polyether moiety was introduced to the phosphinite and the phosphinite modified rhodium complex formed in situ was highly active in the hydroformylation of higher olefins in organic monophase system. After reaction, on cooling to room temperature, the catalyst could precipitate out from organic phase and was easily separated by decantation and reused six times without obvious decreasing in activity
Polyether moiety was introduced to the phosphinite and the phosphinite modified rhodium complex formed in situ was highly active in the hydroformylation of higher olefins in organic monophase system. After reaction, on cooling to room temperature, the catalyst could precipitate out from organic phase and was easily separated by decantation and reused six times without obvious decreasing in activity
2002, 13(5): 472-473
Abstract:
It is reported for the first time that the Pt/TiO2 electrocatalyst was successfully used for the electrocatalytic oxidation of CO in the electrochemical gas sensor with a controlled potential mode. The stability of electrocatalytic activity of the Pt-TiO2 electrocatalyst for the CO oxidation is better than that of Pt.
It is reported for the first time that the Pt/TiO2 electrocatalyst was successfully used for the electrocatalytic oxidation of CO in the electrochemical gas sensor with a controlled potential mode. The stability of electrocatalytic activity of the Pt-TiO2 electrocatalyst for the CO oxidation is better than that of Pt.
2002, 13(5): 474-477
Abstract:
A one-dimensional chain aluminophosphate C1.5H7.5N1.5Al0.5PO4 containing diprotonated racemic 1, 2-diaminopropane cations was synthesized from an alcoholic system. The compound consists of infinite inorganic [AlP2O8] chains of alternately connected AlO4 and PO2(=O)2 tetrahedral units and the racemic template molecules. The macroanionic chains contain corner-shared double four-membered rings.
A one-dimensional chain aluminophosphate C1.5H7.5N1.5Al0.5PO4 containing diprotonated racemic 1, 2-diaminopropane cations was synthesized from an alcoholic system. The compound consists of infinite inorganic [AlP2O8] chains of alternately connected AlO4 and PO2(=O)2 tetrahedral units and the racemic template molecules. The macroanionic chains contain corner-shared double four-membered rings.
2002, 13(5): 478-479
Abstract:
The Pt/C catalyst was prepared with solid phase reaction method (Pt/C(S)) for the first time. Its performances were compared with that prepared by the traditional liquid phase reaction method. The results demonstrate that the electrocatalytic activity of Pt/C catalyst with solid phase reaction method for methanol oxidation is higher than that with liquid phase reaction method. XRD and TEM measurements indicate that the Pt/C(S) possesses low crystalline extent and small particle size.
The Pt/C catalyst was prepared with solid phase reaction method (Pt/C(S)) for the first time. Its performances were compared with that prepared by the traditional liquid phase reaction method. The results demonstrate that the electrocatalytic activity of Pt/C catalyst with solid phase reaction method for methanol oxidation is higher than that with liquid phase reaction method. XRD and TEM measurements indicate that the Pt/C(S) possesses low crystalline extent and small particle size.
2002, 13(5): 480-483
Abstract:
The simultaneous removal of up to 92% of the surfactant template and chemical implantation of transition metal complexes into mesopores has been successfully achieved by treating as-synthesized pure siliceous MCM-41 with supercritical CO2 modified with CH2Cl2/MeOH mixture, resulting in the formation of functionalized material with uniform pore structure.
The simultaneous removal of up to 92% of the surfactant template and chemical implantation of transition metal complexes into mesopores has been successfully achieved by treating as-synthesized pure siliceous MCM-41 with supercritical CO2 modified with CH2Cl2/MeOH mixture, resulting in the formation of functionalized material with uniform pore structure.
2002, 13(5): 484-486
Abstract:
AFM has been utilized to study the surface topography and the local conductivity of nanocrystalline TiO2 films. Improving the local conductivity by Ti(iso-C3H7O)4 treatment is characterized by quantitative analysis of the simultaneous current image. The mechanism of Ti(iso C3H7O)4 treatment is discussed.
AFM has been utilized to study the surface topography and the local conductivity of nanocrystalline TiO2 films. Improving the local conductivity by Ti(iso-C3H7O)4 treatment is characterized by quantitative analysis of the simultaneous current image. The mechanism of Ti(iso C3H7O)4 treatment is discussed.
