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2010 Volume 21 Issue 8
2010, 21(8): 889-891
doi: 10.1016/j.cclet.2010.03.017
Abstract:
Eudistalbin A was isolated from marine tunicate eudistoma album and possess cytotoxic activity (ED50 < 3.2μg/mL) in vitro against the growth of KB human buccal carinoma cells. The synthetic eudistalbin A showed potent inhibitory activity against the breast carcinoma cell line MDA-231 with an IC50 value of 2.1 μmol/L using the metabolic assay MTT. All structures of new compounds were confirmed by 1H NMR, 13C NMR, HRMS and optical rotation.
Eudistalbin A was isolated from marine tunicate eudistoma album and possess cytotoxic activity (ED50 < 3.2μg/mL) in vitro against the growth of KB human buccal carinoma cells. The synthetic eudistalbin A showed potent inhibitory activity against the breast carcinoma cell line MDA-231 with an IC50 value of 2.1 μmol/L using the metabolic assay MTT. All structures of new compounds were confirmed by 1H NMR, 13C NMR, HRMS and optical rotation.
2010, 21(8): 892-896
doi: 10.1016/j.cclet.2010.03.008
Abstract:
An efficient and simple method for the preparation of 5-arylamino-1H-tetrazole and 1-aryl-5-amino-1H-tetrazole derivatives is reported using aluminum (Ⅲ) hydrogensulfate (Al(HSO4)3) as an effective heterogeneous catalyst from secondary arylcyanamides.Generally, when the substitution in arylcyanamide is strongly electron-withdrawing the position of equilibrium would shift toward the isomer of 1-aryl-5-amino-1H-tetrazole (B) and as the electron-donating of substituent increased, the position of equilibrium is shifted toward the isomer of 5-arylamino-1H-tetrazole (A). The present methodology offers several advantages, such as excellent yields, short reaction times, easy work-up and greener conditions.
An efficient and simple method for the preparation of 5-arylamino-1H-tetrazole and 1-aryl-5-amino-1H-tetrazole derivatives is reported using aluminum (Ⅲ) hydrogensulfate (Al(HSO4)3) as an effective heterogeneous catalyst from secondary arylcyanamides.Generally, when the substitution in arylcyanamide is strongly electron-withdrawing the position of equilibrium would shift toward the isomer of 1-aryl-5-amino-1H-tetrazole (B) and as the electron-donating of substituent increased, the position of equilibrium is shifted toward the isomer of 5-arylamino-1H-tetrazole (A). The present methodology offers several advantages, such as excellent yields, short reaction times, easy work-up and greener conditions.
2010, 21(8): 897-901
doi: 10.1016/j.cclet.2010.02.009
Abstract:
Highly active calcium chloride (CaCl2) doped Zn-CoⅢ double metal-cyanide (Ca-DMC) catalysts were firstly reported. Ca-DMCs presented a very higher polymer yield (> 54 kg polymer/g catalyst) at relative low temperature (80-115℃) toward ring-opening polymerization (ROP) of propylene oxide (PO) than did DMC catalysts without modification.
Highly active calcium chloride (CaCl2) doped Zn-CoⅢ double metal-cyanide (Ca-DMC) catalysts were firstly reported. Ca-DMCs presented a very higher polymer yield (> 54 kg polymer/g catalyst) at relative low temperature (80-115℃) toward ring-opening polymerization (ROP) of propylene oxide (PO) than did DMC catalysts without modification.
2010, 21(8): 902-904
doi: 10.1016/j.cclet.2010.03.039
Abstract:
A series of heterocycle-substituted phthalimide derivatives were synthesized. Structurally diverse derivatives with heterocyclic rings, including furan, imidazo [1,2-a] pyridine, 1,3,4-thiadiazine, imidazo [2,1-b] [l,3,4]thiadiazine, pyrazole, 1,2,4-triazolo [3,4-b] [1,3,4]thiadiazine, thiazole and thiazoline, were obtained by the reactions of α-bromoketone intermediate with various nucleophiles containing oxygen, nitrogen and sulfur atom. Their cytotoxic activity was also evaluated against five human cancer cell lines in vitro.
A series of heterocycle-substituted phthalimide derivatives were synthesized. Structurally diverse derivatives with heterocyclic rings, including furan, imidazo [1,2-a] pyridine, 1,3,4-thiadiazine, imidazo [2,1-b] [l,3,4]thiadiazine, pyrazole, 1,2,4-triazolo [3,4-b] [1,3,4]thiadiazine, thiazole and thiazoline, were obtained by the reactions of α-bromoketone intermediate with various nucleophiles containing oxygen, nitrogen and sulfur atom. Their cytotoxic activity was also evaluated against five human cancer cell lines in vitro.
2010, 21(8): 905-910
doi: 10.1016/j.cclet.2010.04.009
Abstract:
A series of novel unsymmetrical N-(4-oxo-2-phenyl-3(4H)-quinazolinoyl)-N-(aryl) acetamidines was synthesized by reacting ethyl(1E)-N-(4-oxo-2-phenylquinazolin-3(4H)-yl)ethanimidoate (2) and suitable reactive aromatic amines. Structures' determina-tion of the synthesized compounds was carried out using spectroscopic techniques including IR, 1H NMR, and mass spectrometry.Structural effects on reactivity were also studied.
A series of novel unsymmetrical N-(4-oxo-2-phenyl-3(4H)-quinazolinoyl)-N-(aryl) acetamidines was synthesized by reacting ethyl(1E)-N-(4-oxo-2-phenylquinazolin-3(4H)-yl)ethanimidoate (2) and suitable reactive aromatic amines. Structures' determina-tion of the synthesized compounds was carried out using spectroscopic techniques including IR, 1H NMR, and mass spectrometry.Structural effects on reactivity were also studied.
2010, 21(8): 911-193
doi: 10.1016/j.cclet.2010.03.001
Abstract:
The kinetics of aniline degradation by persulfate processes with iron (Ⅱ) activation at ambient temperature was investigated in this study. With iron (Ⅱ) as initiator, the oxidation reactions were found to follow a biphasic rate phenomenon:a rapid transformation followed by a slow but sustained oxidation process. In the first 30 s, the reaction mainly relies on the persulfate-Fe2+ reaction in which aniline is oxidized rapidly. After 30 s, the aniline was still oxidized but the rate of reaction tended to be slower and the rates were clearly linear-proportional. After the initial fast oxidation, the reactions appeared to follow a pseudo-first-order model.
The kinetics of aniline degradation by persulfate processes with iron (Ⅱ) activation at ambient temperature was investigated in this study. With iron (Ⅱ) as initiator, the oxidation reactions were found to follow a biphasic rate phenomenon:a rapid transformation followed by a slow but sustained oxidation process. In the first 30 s, the reaction mainly relies on the persulfate-Fe2+ reaction in which aniline is oxidized rapidly. After 30 s, the aniline was still oxidized but the rate of reaction tended to be slower and the rates were clearly linear-proportional. After the initial fast oxidation, the reactions appeared to follow a pseudo-first-order model.
2010, 21(8): 914-918
doi: 10.1016/j.cclet.2010.04.008
Abstract:
Green, mild and efficient iodination of hydroxylated aromatic aldehydes and ketones using iodine and iodic acid in the solid-state by grinding under solvent-free conditions at room temperature. This method provides several advantages such as environmentally friendly, short reaction times, high yields, non-hazardous and simple work-up procedure.
Green, mild and efficient iodination of hydroxylated aromatic aldehydes and ketones using iodine and iodic acid in the solid-state by grinding under solvent-free conditions at room temperature. This method provides several advantages such as environmentally friendly, short reaction times, high yields, non-hazardous and simple work-up procedure.
2010, 21(8): 919-921
doi: 10.1016/j.cclet.2010.03.004
Abstract:
Acetonylacetone 1 was treated with thiourea, aniline, glycine and glutamic acid to give pyrrole derivatives 2, 3, 5, and 9by Paal-Knorr reaction, respectively. Then 3 was successfully transformed into the related pyrrole derivative 4 by Mannich reaction.Compounds 6, 7 and 8 were obtained by reacting 5 with phenethyl alcohol, phenylallylic alcohol and leaf alcohol by esterification reactions, respectively. The structures of all new products were elucidated by IR, NMR and HRMS spectra.
Acetonylacetone 1 was treated with thiourea, aniline, glycine and glutamic acid to give pyrrole derivatives 2, 3, 5, and 9by Paal-Knorr reaction, respectively. Then 3 was successfully transformed into the related pyrrole derivative 4 by Mannich reaction.Compounds 6, 7 and 8 were obtained by reacting 5 with phenethyl alcohol, phenylallylic alcohol and leaf alcohol by esterification reactions, respectively. The structures of all new products were elucidated by IR, NMR and HRMS spectra.
2010, 21(8): 922-926
doi: 10.1016/j.cclet.2010.03.013
Abstract:
Sulfuric acid immobilized on silica gel is designed as a very useful catalyst for synthesis of 2,3-unsaturated glycopyranosides.This handy,metal-free,environment friendly transformation provides high yields and α-stereoselectivities in a very few amount (< 0.02 eq.=of catalyst and in short reaction times (< 10 min).
Sulfuric acid immobilized on silica gel is designed as a very useful catalyst for synthesis of 2,3-unsaturated glycopyranosides.This handy,metal-free,environment friendly transformation provides high yields and α-stereoselectivities in a very few amount (< 0.02 eq.=of catalyst and in short reaction times (< 10 min).
2010, 21(8): 927-930
doi: 10.1016/j.cclet.2010.03.014
Abstract:
A three component one-pot protocol was investigated for the synthesis of methylene bis isoxazolo[4,5-b]-pyridine-N-oxides from commercially available materials.
A three component one-pot protocol was investigated for the synthesis of methylene bis isoxazolo[4,5-b]-pyridine-N-oxides from commercially available materials.
2010, 21(8): 931-934
doi: 10.1016/j.cclet.2010.03.027
Abstract:
In the presence of diethyl 1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylate (DHP) and a catalytic amount of potassium iodide,several α-halo ketones were easily reduced to the corresponding ketones in acetone media.The procedure presented here showed several merits such as short reaction time,practical experimental and isolated procedure,and excellent yields of products.
In the presence of diethyl 1,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylate (DHP) and a catalytic amount of potassium iodide,several α-halo ketones were easily reduced to the corresponding ketones in acetone media.The procedure presented here showed several merits such as short reaction time,practical experimental and isolated procedure,and excellent yields of products.
2010, 21(8): 935-938
doi: 10.1016/j.cclet.2010.03.028
Abstract:
One-step method for the synthesis of secondary aliphatic amine substituted nitrobenzaldehyde was developed.In the presence of Pd catalyst,halogenated nitrobenzaldehyde could be smoothly coupled with secondary aliphatic amine to give the target product in hexamethylphosphamide (HMPT) media without the protection of aldehyde groups.
One-step method for the synthesis of secondary aliphatic amine substituted nitrobenzaldehyde was developed.In the presence of Pd catalyst,halogenated nitrobenzaldehyde could be smoothly coupled with secondary aliphatic amine to give the target product in hexamethylphosphamide (HMPT) media without the protection of aldehyde groups.
2010, 21(8): 939-942
doi: 10.1016/j.cclet.2010.03.016
Abstract:
A series of quinoline-3-carbonitrile derivatives were designed and synthesized.Their cytotoxicity in vitro against four cancer cell lines (A549,HT-29,MDA-MB-231 and SMMC-7721) were evaluated by standard MTT assay.The pharmacological results showed that most of the prepared compounds displayed excellent selective cytotoxicity toward SMMC-7721 cell line.Among them,compounds 7c,7e,11b,11f and 11g were more active than Gefitinb against SMMC-7721 cell line.
A series of quinoline-3-carbonitrile derivatives were designed and synthesized.Their cytotoxicity in vitro against four cancer cell lines (A549,HT-29,MDA-MB-231 and SMMC-7721) were evaluated by standard MTT assay.The pharmacological results showed that most of the prepared compounds displayed excellent selective cytotoxicity toward SMMC-7721 cell line.Among them,compounds 7c,7e,11b,11f and 11g were more active than Gefitinb against SMMC-7721 cell line.
2010, 21(8): 943-946
doi: 10.1016/j.cclet.2010.04.024
Abstract:
A new macrocyclic diterpenoid,named kansuinine J (1),was isolated from the roots of Euphorbia kansui.Its structure was characterized on the basis of spectroscopic analysis.
A new macrocyclic diterpenoid,named kansuinine J (1),was isolated from the roots of Euphorbia kansui.Its structure was characterized on the basis of spectroscopic analysis.
2010, 21(8): 947-950
doi: 10.1016/j.cclet.2010.03.025
Abstract:
Azalomycin F4a 2-ethylpentyl ester,a new 36-membered macrocyclic lactone antibiotic,was isolated from mangrove actinomycete Streptomyces sp.211726.Its structure was elucidated on the basis of spectroscopic data.The compound showed broad-spectrum antifungal activity and moderate cytotoxicity against human colon tumor cell HCT-116.
Azalomycin F4a 2-ethylpentyl ester,a new 36-membered macrocyclic lactone antibiotic,was isolated from mangrove actinomycete Streptomyces sp.211726.Its structure was elucidated on the basis of spectroscopic data.The compound showed broad-spectrum antifungal activity and moderate cytotoxicity against human colon tumor cell HCT-116.
2010, 21(8): 951-954
doi: 10.1016/j.cclet.2010.02.025
Abstract:
The possibility of direct analytical applications of ferrate (Ⅵ) solution,which was freshly electrogenerated in low-concentration NaOH electrolyte,was studied by a flow-injection-chemiluminescence (FI-CL) system.It was found that some inorganic ions,organic molecule and biomolecule could enhance the chemiluminescence emission caused by ferrate (Ⅵ)-Iuminol reaction.Ⅴ (Ⅴ),Ca (Ⅱ),Mg (Ⅱ),phloroglucinol,and bovine hemoglobin (Hb) chosen as samples were successfully detected by this developed method.The analytical characteristics of the system for the analytes determination including linear ranges,correlation coefficients,limits of detection combined with FI analysis were studied.
The possibility of direct analytical applications of ferrate (Ⅵ) solution,which was freshly electrogenerated in low-concentration NaOH electrolyte,was studied by a flow-injection-chemiluminescence (FI-CL) system.It was found that some inorganic ions,organic molecule and biomolecule could enhance the chemiluminescence emission caused by ferrate (Ⅵ)-Iuminol reaction.Ⅴ (Ⅴ),Ca (Ⅱ),Mg (Ⅱ),phloroglucinol,and bovine hemoglobin (Hb) chosen as samples were successfully detected by this developed method.The analytical characteristics of the system for the analytes determination including linear ranges,correlation coefficients,limits of detection combined with FI analysis were studied.
2010, 21(8): 955-958
doi: 10.1016/j.cclet.2010.03.029
Abstract:
A new indirect inhibitive immunoassay using surface plasmon resonance (SPR)coupled with molecularly imprinted polymer (MIP)was developed.A sulfamethoxazole (SMX)MIP coating capillary was produced and used as an in-tube solid phase extraction (SPE)device.The MIP coating formed a nanometer film on the inner wall of the capillary.The anti-SMX mono-antibody was inhibited by SMX extracted by the MIP coating in a dose-dependent manner.The calibration curve was generated by linear fit over the range of 0.04-10.00 ng/mL.The limit of detection was 0.01 ng/mL.This method has high sensitivity and can be performed automatically.
A new indirect inhibitive immunoassay using surface plasmon resonance (SPR)coupled with molecularly imprinted polymer (MIP)was developed.A sulfamethoxazole (SMX)MIP coating capillary was produced and used as an in-tube solid phase extraction (SPE)device.The MIP coating formed a nanometer film on the inner wall of the capillary.The anti-SMX mono-antibody was inhibited by SMX extracted by the MIP coating in a dose-dependent manner.The calibration curve was generated by linear fit over the range of 0.04-10.00 ng/mL.The limit of detection was 0.01 ng/mL.This method has high sensitivity and can be performed automatically.
2010, 21(8): 959-962
doi: 10.1016/j.cclet.2010.03.033
Abstract:
TiO2 colloid was prepared by the sol-gel method and was bladed on transparent conduction glass to made nanoporous electrode.The impedance performance of TiO2 electrode was studied at various bias potential.A simplified equivalent circuit was proposed to investigate the charge transport impedance of TiO2 film and good fitting results were obtained.
TiO2 colloid was prepared by the sol-gel method and was bladed on transparent conduction glass to made nanoporous electrode.The impedance performance of TiO2 electrode was studied at various bias potential.A simplified equivalent circuit was proposed to investigate the charge transport impedance of TiO2 film and good fitting results were obtained.
2010, 21(8): 963-967
doi: 10.1016/j.cclet.2010.03.015
Abstract:
The interactions of carbofuran and DNA were studied using voltammetry and fluorescence spectroscopy.The formation of carbofuran-DNA makes the current peak of DNA decreased by voltammetry method.The binding number (n) and constant (Ka) for complex carbofuran-DNA were calculated to be 1.06±0.04 and 0.11±0.03 mol-1 L,respectively by fluorescence measurement.Chemometrics approach,such as singular valueal species in the drug-DNA binding process.And the pure spectra and concentration profiles in the kinetic system were clearly deduced by multivariate curve resolution alternating least squares (MCR-ALS) with the initial estimates by evolving factor analysis (EFA).
The interactions of carbofuran and DNA were studied using voltammetry and fluorescence spectroscopy.The formation of carbofuran-DNA makes the current peak of DNA decreased by voltammetry method.The binding number (n) and constant (Ka) for complex carbofuran-DNA were calculated to be 1.06±0.04 and 0.11±0.03 mol-1 L,respectively by fluorescence measurement.Chemometrics approach,such as singular valueal species in the drug-DNA binding process.And the pure spectra and concentration profiles in the kinetic system were clearly deduced by multivariate curve resolution alternating least squares (MCR-ALS) with the initial estimates by evolving factor analysis (EFA).
2010, 21(8): 968-972
doi: 10.1016/j.cclet.2010.03.010
Abstract:
The luminescent properties of microwave discharge electrodeless mercury lamp (MDEL-Hg) which was ignited within the resonant cavity and photolysis of hydrogen sulfide with low concentration were studied in this paper.Experiment results indicated that the Interior MDEL-Hg could be made the best of energy utilization and the efficiency of photolysis of H2S was very significant under the experimental conditions with the initial H2S concentration of 7.9 mg m-3.With residence time of 1.5 s,the removal efficiency of hydrogen sulfide was 91%,the absolute removal amount (ARA) was 3.24 μg s-1 and the energy consumption was 58.23 mg (kW h)-1.
The luminescent properties of microwave discharge electrodeless mercury lamp (MDEL-Hg) which was ignited within the resonant cavity and photolysis of hydrogen sulfide with low concentration were studied in this paper.Experiment results indicated that the Interior MDEL-Hg could be made the best of energy utilization and the efficiency of photolysis of H2S was very significant under the experimental conditions with the initial H2S concentration of 7.9 mg m-3.With residence time of 1.5 s,the removal efficiency of hydrogen sulfide was 91%,the absolute removal amount (ARA) was 3.24 μg s-1 and the energy consumption was 58.23 mg (kW h)-1.
2010, 21(8): 973-975
doi: 10.1016/j.cclet.2010.03.005
Abstract:
Trimethoxysilyl-functionalized PPEK (PKGS) films bad been designed to serve as wear resistant coatings for silicon surfaces.These surface films were formed by a dip-coating technique applied to self-assembled monolayers (SAMs).The formation and wetting behavior of PKGS films were characterized by means of contact angle measurement.The friction coefficient of the film prepared is very low (about 0.1),and the anti-wear behavior is good,with a lack of failure after sliding over 1800 s.
Trimethoxysilyl-functionalized PPEK (PKGS) films bad been designed to serve as wear resistant coatings for silicon surfaces.These surface films were formed by a dip-coating technique applied to self-assembled monolayers (SAMs).The formation and wetting behavior of PKGS films were characterized by means of contact angle measurement.The friction coefficient of the film prepared is very low (about 0.1),and the anti-wear behavior is good,with a lack of failure after sliding over 1800 s.
2010, 21(8): 976-978
doi: 10.1016/j.cclet.2010.04.023
Abstract:
A new aromatic diacid monomer containing pyridine unit,4-phenyl-2,6-bis [4-(4-carboxyphenoxy) phenyl]pyridine 3,was successfully synthesized in three steps,starting from 4-hydroxyacetophenone.The corresponding pyridine-containing polybenzi-midazole was prepared via polycondensation of 3 with tetraaminodiphenyl ether (TADE) in poly (phosphoric acid) (PPA).The resulting polybenzimidazole exhibits excellent solubility,good thermal stabilities and high thermal resistance.
A new aromatic diacid monomer containing pyridine unit,4-phenyl-2,6-bis [4-(4-carboxyphenoxy) phenyl]pyridine 3,was successfully synthesized in three steps,starting from 4-hydroxyacetophenone.The corresponding pyridine-containing polybenzi-midazole was prepared via polycondensation of 3 with tetraaminodiphenyl ether (TADE) in poly (phosphoric acid) (PPA).The resulting polybenzimidazole exhibits excellent solubility,good thermal stabilities and high thermal resistance.
2010, 21(8): 979-982
doi: 10.1016/j.cclet.2010.01.027
Abstract:
A new method for the preparation of microcapsule-supported palladium catalyst was described.The highly monodisperse crosslinked polystyrene microcapsules containing phosphine ligand were synthesized by the self-assembling of phase separated polymer (SaPSeP) method using diphenyl (4-vinylphenyl) phosphine and divinylbenzene as a monomer and crosslinking agent,respectively,and 2,2'-azobisisobutyronitrile (AIBN) as an initiator within the droplets of oil-in-water (O/W) emulsions,which were prepared by using the Shirasu Porous Glass (SPG) membrane emulsification technique.The prepared microcapsule-supported palladium catalyst exhibited high catalytic activity for Heck reaction and can be reused several times without loss of activity.
A new method for the preparation of microcapsule-supported palladium catalyst was described.The highly monodisperse crosslinked polystyrene microcapsules containing phosphine ligand were synthesized by the self-assembling of phase separated polymer (SaPSeP) method using diphenyl (4-vinylphenyl) phosphine and divinylbenzene as a monomer and crosslinking agent,respectively,and 2,2'-azobisisobutyronitrile (AIBN) as an initiator within the droplets of oil-in-water (O/W) emulsions,which were prepared by using the Shirasu Porous Glass (SPG) membrane emulsification technique.The prepared microcapsule-supported palladium catalyst exhibited high catalytic activity for Heck reaction and can be reused several times without loss of activity.
2010, 21(8): 983-986
doi: 10.1016/j.cclet.2010.03.030
Abstract:
Metallic cobalt was deposited on acetylene black to synthesize a composite Co/C by chemical reduction method.A platinum-free electrocatalyst Co-N/C (8 0 0) for oxygen reduction reaction (ORR) was synthesized by mixing the composite Co/C with urea and heat-treating at 800℃.The results from linear sweep voltammograms indicated that the Co-N/C (8 0 0) is active to ORR.The β-Co and cobalt oxides are not the active site of the catalyst Co-N/C.However,the existence of cobalt facilitated the modification of nitrogen to carbon black and led to the formation of active site of catalyst Co-N/C (8 0 0).
Metallic cobalt was deposited on acetylene black to synthesize a composite Co/C by chemical reduction method.A platinum-free electrocatalyst Co-N/C (8 0 0) for oxygen reduction reaction (ORR) was synthesized by mixing the composite Co/C with urea and heat-treating at 800℃.The results from linear sweep voltammograms indicated that the Co-N/C (8 0 0) is active to ORR.The β-Co and cobalt oxides are not the active site of the catalyst Co-N/C.However,the existence of cobalt facilitated the modification of nitrogen to carbon black and led to the formation of active site of catalyst Co-N/C (8 0 0).
2010, 21(8): 987-980
doi: 10.1016/j.cclet.2010.04.022
Abstract:
With high surface area, open porosity and high efficiency, a catalyst was prepared and firstly employed in electrocatalytic reduction of CO2 and electrosynthesis of dimethyl carbonate (DMC). The electrochemical property for electrocatalytic reduction of CO2 in ionic liquid was studied by cyclic voitammogram (CV). The effects of various reaction variables like temperature, working potential and cathode materials on the electrocatalytic performance were also investigated. 80% yield of DMC was obtained under the optimal reaction conditions.
With high surface area, open porosity and high efficiency, a catalyst was prepared and firstly employed in electrocatalytic reduction of CO2 and electrosynthesis of dimethyl carbonate (DMC). The electrochemical property for electrocatalytic reduction of CO2 in ionic liquid was studied by cyclic voitammogram (CV). The effects of various reaction variables like temperature, working potential and cathode materials on the electrocatalytic performance were also investigated. 80% yield of DMC was obtained under the optimal reaction conditions.
2010, 21(8): 991-994
doi: 10.1016/j.cclet.2010.02.010
Abstract:
A simple and general strategy is described for preparing network supported catalyst through a one-pot synthetic procedure using supramolecular gel as template. This procedure directly attaches iigand to support during fabricating the support. Using this strategy, supported CuBr/di-(2-picolyl) amine catalyst with U-shaped fibrillar network was prepared and used in atom transfer radical polymerization of methyl methacrylate. XPS and SEM characterization of the catalyst revealed homogeneous distribution of ligand, sufficient reactive sites, adequate mechanical strength and macroporosity. The polymerization results demonstrated high activity and reusability of such catalyst. This strategy might be extended to other supported catalysts used in column reactors.
A simple and general strategy is described for preparing network supported catalyst through a one-pot synthetic procedure using supramolecular gel as template. This procedure directly attaches iigand to support during fabricating the support. Using this strategy, supported CuBr/di-(2-picolyl) amine catalyst with U-shaped fibrillar network was prepared and used in atom transfer radical polymerization of methyl methacrylate. XPS and SEM characterization of the catalyst revealed homogeneous distribution of ligand, sufficient reactive sites, adequate mechanical strength and macroporosity. The polymerization results demonstrated high activity and reusability of such catalyst. This strategy might be extended to other supported catalysts used in column reactors.
2010, 21(8): 995-998
doi: 10.1016/j.cclet.2010.01.022
Abstract:
Bamboo charcoal polyester fiber (BC-PET) has been widely applied in home textiles, functional clothing and hydra-balance material, due to their strong adsorptivity, good resolvability, anti-statics, deodorization, antibacterial, anion releasing and far infrared emitting. But BC-PET is black and difficult to be dyed, and its application is limited. In this article, nitric acid was used to treat the surface of bamboo charcoal (BC) powder, and BC powder was modified by titanium dioxide sol to prepare white bamboo charcoal (white-BC) particle. White bamboo charcoal polyester fiber (white-BC-PET) was obtained by mixing white-BC and polyester (PET) resin in double screw extruder. Performance of fiber was tested referring to national standard GB/TI4464-2008 of common PET fiber and most of its indicators have already exceeded GB the level of excellent product. SEM photographs showed that the white-BC was uniformly distributed inside or on the surface of fiber. The white-BC-PET could absorb some aniline and had at least 90% anti-bacterial rate. The anti-bacterial rate could have almost been kept after it was washed 50 times. It was hopeful to be applied in various fields as functional fiber.
Bamboo charcoal polyester fiber (BC-PET) has been widely applied in home textiles, functional clothing and hydra-balance material, due to their strong adsorptivity, good resolvability, anti-statics, deodorization, antibacterial, anion releasing and far infrared emitting. But BC-PET is black and difficult to be dyed, and its application is limited. In this article, nitric acid was used to treat the surface of bamboo charcoal (BC) powder, and BC powder was modified by titanium dioxide sol to prepare white bamboo charcoal (white-BC) particle. White bamboo charcoal polyester fiber (white-BC-PET) was obtained by mixing white-BC and polyester (PET) resin in double screw extruder. Performance of fiber was tested referring to national standard GB/TI4464-2008 of common PET fiber and most of its indicators have already exceeded GB the level of excellent product. SEM photographs showed that the white-BC was uniformly distributed inside or on the surface of fiber. The white-BC-PET could absorb some aniline and had at least 90% anti-bacterial rate. The anti-bacterial rate could have almost been kept after it was washed 50 times. It was hopeful to be applied in various fields as functional fiber.
2010, 21(8): 999-1002
doi: 10.1016/j.cclet.2010.04.021
Abstract:
SnO2 nanorods were deposited on the Si substrates in an aqueous solution containing both SnCl4 and CO(NH2)2. It is found that different self-assembled patterns of SnO2 nanorods can be obtained by changing the deposition conditions such as the molar ratio of CO(NH2)2 to SnCl4 and the pretreatment of the substrate. Scattered SnO2 nanorods, for example, can be changed into flower-like patterns when the molar ratio of CO(NH2)2 to SnCl4 is raised, and well-aligned nanorod arrays can be formed when the pretreatment of the snbstrate is changed. In addition, some interesting patterns, e.g. tree-like patterns, can also be observed.
SnO2 nanorods were deposited on the Si substrates in an aqueous solution containing both SnCl4 and CO(NH2)2. It is found that different self-assembled patterns of SnO2 nanorods can be obtained by changing the deposition conditions such as the molar ratio of CO(NH2)2 to SnCl4 and the pretreatment of the substrate. Scattered SnO2 nanorods, for example, can be changed into flower-like patterns when the molar ratio of CO(NH2)2 to SnCl4 is raised, and well-aligned nanorod arrays can be formed when the pretreatment of the snbstrate is changed. In addition, some interesting patterns, e.g. tree-like patterns, can also be observed.
2010, 21(8): 1003-1006
doi: 10.1016/j.cclet.2010.02.008
Abstract:
Polymethyl methacrylate cadmium was grafted on TiO2 surface via the surface initiated atomic transfer radical polymerization of methyl methacrylate cadmium from a surface tether initiator. The coordinated cadmium as the source precursor reacts with H2S generates CdS nanoscrystal on TiO2 surface. The grain size of CdS is about 5 nm and stabilized by tether polymer chains. The light absorption of CdS/TiO2 is expanded to visible light region.
Polymethyl methacrylate cadmium was grafted on TiO2 surface via the surface initiated atomic transfer radical polymerization of methyl methacrylate cadmium from a surface tether initiator. The coordinated cadmium as the source precursor reacts with H2S generates CdS nanoscrystal on TiO2 surface. The grain size of CdS is about 5 nm and stabilized by tether polymer chains. The light absorption of CdS/TiO2 is expanded to visible light region.
2010, 21(8): 1007-1010
doi: 10.1016/j.cclet.2010.02.006
Abstract:
Nitration of 4,4'-biphenyldicarboxylic acid (BPDC) was studied and an aromatic carboxylic acid containing two nitro groups was synthesized and characterized through elemental analysis and IR spectra. Crystal structure of DNBPDC (DNBPDC=2,2'-dinitro-4,4'-biphenyldicarboxylic acid) was determined by X-ray single crystal diffraction and the thermal decomposition was carried out through DSC and TG-DTG analyses.
Nitration of 4,4'-biphenyldicarboxylic acid (BPDC) was studied and an aromatic carboxylic acid containing two nitro groups was synthesized and characterized through elemental analysis and IR spectra. Crystal structure of DNBPDC (DNBPDC=2,2'-dinitro-4,4'-biphenyldicarboxylic acid) was determined by X-ray single crystal diffraction and the thermal decomposition was carried out through DSC and TG-DTG analyses.
2010, 21(8): 1011-1014
doi: 10.1016/j.cclet.2010.04.010
Abstract:
A membrane composed of an alginate (ALG) layer and a chitosan (CHS) layer with sustained antimicrobial efficacy was prepared. Ciprofloxacin HCI (CIP) was incorporated into the ALG layer. Morphological feature of the composite membrane was analyzed by scanning electron microscopy (SEM). Water uptake capacity, in vitro drug release, and in vitro antimicrobial activity were evaluated. The composite membrane exhibited perfect binding characteristic between the two layers. The water uptake capacity of all the membranes was above 800%. The CIP could release from the composite membranes for 48 h. The membrane could control the bacterial growth persistently. The results suggested that this CHS/ALG composite membrane incorporated with CIP had the potential for wound dressing application.
A membrane composed of an alginate (ALG) layer and a chitosan (CHS) layer with sustained antimicrobial efficacy was prepared. Ciprofloxacin HCI (CIP) was incorporated into the ALG layer. Morphological feature of the composite membrane was analyzed by scanning electron microscopy (SEM). Water uptake capacity, in vitro drug release, and in vitro antimicrobial activity were evaluated. The composite membrane exhibited perfect binding characteristic between the two layers. The water uptake capacity of all the membranes was above 800%. The CIP could release from the composite membranes for 48 h. The membrane could control the bacterial growth persistently. The results suggested that this CHS/ALG composite membrane incorporated with CIP had the potential for wound dressing application.
