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2006 Volume 17 Issue 1
2006, 17(1): 1-4
Abstract:
Enamines, promoted by the samarium/samarium diiodide mixed reagent, were synthesized via the cross-coupling of thioamides and diarylketones in good yields.
Enamines, promoted by the samarium/samarium diiodide mixed reagent, were synthesized via the cross-coupling of thioamides and diarylketones in good yields.
2006, 17(1): 5-8
Abstract:
Artabotrine 1 is a novel N-methoxylated 4, 5-dioxoaporphine alkaloid which has been reported to be cytotoxic against P-388 cells. The total synthesis of 1 was carried out, and one of its analogue, N-methoxycepharadione B 2, was also synthesized. Both of the alkaloids and several intermediates were cytotoxic to several selected tumor cell lines.
Artabotrine 1 is a novel N-methoxylated 4, 5-dioxoaporphine alkaloid which has been reported to be cytotoxic against P-388 cells. The total synthesis of 1 was carried out, and one of its analogue, N-methoxycepharadione B 2, was also synthesized. Both of the alkaloids and several intermediates were cytotoxic to several selected tumor cell lines.
2006, 17(1): 9-11
Abstract:
Reaction of 12-membered macrolide 1 with lead tetraacetate in dichloromethane afforded an unexpected, novel oxidative N-demethyl product 3.
Reaction of 12-membered macrolide 1 with lead tetraacetate in dichloromethane afforded an unexpected, novel oxidative N-demethyl product 3.
2006, 17(1): 12-14
Abstract:
Regioselective decomposition of 11-substituted-16α, 17α-methyleneazopregna-1, 4-dien-3, 20-dione I proceeded smoothly through thermal decomposition in the presence of BF3·Et2O or HC1O4with high yields. I was converted to 11-substituted-16-methylpregna-1, 4, 16(17)-trien-3, 20-dione Ⅱ by the thermal decomposition, while with HClO4 as a catalyst, 11-substituted-16α, 17α-methylenepregna-1, 4-dien-3, 20-dione Ⅲ was the main product.However, when BF3·Et20 was used as catalyst, a mixture of Ⅱ and Ⅲ (1:3) was obtained.
Regioselective decomposition of 11-substituted-16α, 17α-methyleneazopregna-1, 4-dien-3, 20-dione I proceeded smoothly through thermal decomposition in the presence of BF3·Et2O or HC1O4with high yields. I was converted to 11-substituted-16-methylpregna-1, 4, 16(17)-trien-3, 20-dione Ⅱ by the thermal decomposition, while with HClO4 as a catalyst, 11-substituted-16α, 17α-methylenepregna-1, 4-dien-3, 20-dione Ⅲ was the main product.However, when BF3·Et20 was used as catalyst, a mixture of Ⅱ and Ⅲ (1:3) was obtained.
2006, 17(1): 15-18
Abstract:
The reaction of p- and/α-subtituted benzyl alcohols in CaY-zeolite produced the corresponding dibenzyl ethers and/or benzyl toluenes as the principal products.
The reaction of p- and/α-subtituted benzyl alcohols in CaY-zeolite produced the corresponding dibenzyl ethers and/or benzyl toluenes as the principal products.
2006, 17(1): 19-22
Abstract:
5-(5"-Substituted phenyl-[1", 3", 4"]oxadiazol-2"-yl methylsulfanyl)-3-pyridin-3'-yl-[1,2,4] triazol-4-yl amines 1a-j were quaternarized with methyl iodide to afford the corresponding methyl pyridinium salts 2a-j. The reduction of compounds 2 with NaBH4 in methanol gave the target compounds 5-(5"-substituted phenyl-[1", 3", 4"]oxadiazol-2"-yl methylsulfanyl)-3-(1'-methyl-1', 2', 5', 6'-tetrahydropyridin-3'-yl)-[1,2,4]triazol-4-ylamines 3a-j. The endothelium vascular relaxing activity of the target compounds were screened.
5-(5"-Substituted phenyl-[1", 3", 4"]oxadiazol-2"-yl methylsulfanyl)-3-pyridin-3'-yl-[1,2,4] triazol-4-yl amines 1a-j were quaternarized with methyl iodide to afford the corresponding methyl pyridinium salts 2a-j. The reduction of compounds 2 with NaBH4 in methanol gave the target compounds 5-(5"-substituted phenyl-[1", 3", 4"]oxadiazol-2"-yl methylsulfanyl)-3-(1'-methyl-1', 2', 5', 6'-tetrahydropyridin-3'-yl)-[1,2,4]triazol-4-ylamines 3a-j. The endothelium vascular relaxing activity of the target compounds were screened.
2006, 17(1): 23-26
Abstract:
Novel water-soluble prodrugs of combretastatin A-4(5-8) were synthesized and evaluated for their in vitro cytotoxicity against lung carcinoma A549. Compound 5, bearing phosphoryl choline (PC) moiety, showed 90% inhibition at 32μg/mL concentration after 24 h. The findings showed the PC derivative would be a promising candidate for the development of new water-soluble prodrug of cytotoxic combretastatin A-4.
Novel water-soluble prodrugs of combretastatin A-4(5-8) were synthesized and evaluated for their in vitro cytotoxicity against lung carcinoma A549. Compound 5, bearing phosphoryl choline (PC) moiety, showed 90% inhibition at 32μg/mL concentration after 24 h. The findings showed the PC derivative would be a promising candidate for the development of new water-soluble prodrug of cytotoxic combretastatin A-4.
2006, 17(1): 27-30
Abstract:
A new abeotaxane was isolated from the seeds of Taxus mairei. Its structure was determined to be 2α, 5o, 13α-trihydroxy-7β, 10β-diacetoxy-2(3→20) abeotaxa-4(20), 11-dien-9-one on the basis of 1D and 2D spectral analysis.
A new abeotaxane was isolated from the seeds of Taxus mairei. Its structure was determined to be 2α, 5o, 13α-trihydroxy-7β, 10β-diacetoxy-2(3→20) abeotaxa-4(20), 11-dien-9-one on the basis of 1D and 2D spectral analysis.
2006, 17(1): 31-34
Abstract:
Two new steroidal glycosides named Lm-4(1) and Lm-5(2) were isolated from the tubers of Liriope muscari. Their structures were elucidated by 1D and 2D NMR, ESI/MALDIMS techniques, and chemical methods.
Two new steroidal glycosides named Lm-4(1) and Lm-5(2) were isolated from the tubers of Liriope muscari. Their structures were elucidated by 1D and 2D NMR, ESI/MALDIMS techniques, and chemical methods.
2006, 17(1): 35-37
Abstract:
A new biphenyl glycoside along with six known compounds were isolated from the water soluble fraction of the fresh leaves of Eriobotrya japonica. Its structure was elucidated as 5, 5'-dihydroxy-3'-methoxybiphenyl-2-O-β-D-glucopyranoside on the basis of cellulase hydrolysis and spectroscopic analysis.
A new biphenyl glycoside along with six known compounds were isolated from the water soluble fraction of the fresh leaves of Eriobotrya japonica. Its structure was elucidated as 5, 5'-dihydroxy-3'-methoxybiphenyl-2-O-β-D-glucopyranoside on the basis of cellulase hydrolysis and spectroscopic analysis.
2006, 17(1): 38-40
Abstract:
A new daphnane diterpene was isolated from the root barks of Daphne tangutica Maxim.Its structure was elucidated as 1, 2α-dihydro-20-palimoyldaphnetoxin by the spectroscopic evidence including 2D-NMR.
A new daphnane diterpene was isolated from the root barks of Daphne tangutica Maxim.Its structure was elucidated as 1, 2α-dihydro-20-palimoyldaphnetoxin by the spectroscopic evidence including 2D-NMR.
2006, 17(1): 41-44
Abstract:
Three viscotoxins have been isolated from Chinese mistletoe, Viscum coloratum (Kom.) Nakai. The primary structures were determined unambiguously by the combination of Edman degradation, endoproteinase Elu-c digestion, and Q-TOF mass spectrometry. One was identified as viscotoxin C1, which was for the first time isolated from Chinese mistletoe. The other two were new polypeptides, named as viscotoxin B5 and viscotoxin B8. Pharmacological studies showed that the polypeptides exhibit distinct cytotoxicity to human cancer cells.
Three viscotoxins have been isolated from Chinese mistletoe, Viscum coloratum (Kom.) Nakai. The primary structures were determined unambiguously by the combination of Edman degradation, endoproteinase Elu-c digestion, and Q-TOF mass spectrometry. One was identified as viscotoxin C1, which was for the first time isolated from Chinese mistletoe. The other two were new polypeptides, named as viscotoxin B5 and viscotoxin B8. Pharmacological studies showed that the polypeptides exhibit distinct cytotoxicity to human cancer cells.
2006, 17(1): 45-48
Abstract:
Two new diterpenes, 2β, 16β-ent-kaurane diol, 15α, 16α-epoxy-17β-al-ent-kaurane-19-oic acid were isolated from Helianthus annuus L. Their structures were determined by spectroscopic evidences.
Two new diterpenes, 2β, 16β-ent-kaurane diol, 15α, 16α-epoxy-17β-al-ent-kaurane-19-oic acid were isolated from Helianthus annuus L. Their structures were determined by spectroscopic evidences.
2006, 17(1): 49-52
Abstract:
Simulated enantiomeric excess of glutamic acid was determined by a lab-made sixteen-channel capillary array electrophoresis with confocal fluorescent rotary scanner. The experimental results indicated that the capillary array electrophoresis method can accurately determine the enantiomeric excess of glutamic acid and can be used for high-throughput screening system for combinatorial asymmetric catalysis.
Simulated enantiomeric excess of glutamic acid was determined by a lab-made sixteen-channel capillary array electrophoresis with confocal fluorescent rotary scanner. The experimental results indicated that the capillary array electrophoresis method can accurately determine the enantiomeric excess of glutamic acid and can be used for high-throughput screening system for combinatorial asymmetric catalysis.
2006, 17(1): 53-56
Abstract:
A laser-induced resonance light scattering (RLS) imaging method to determine heparin is described based on the high light scattering emission power of the aggregation species of heparin with α, β, γ, δtetra(4-trimethylaminoniumphenyl)prophyrin (TAPP) in solution. By imaging the light scattering signals of the aggregation species, we proposed the method to determine the heparin with a detection range of 0.02-0.6μg/mL and the detection limit (3σ) of 1.3 ng/mL.
A laser-induced resonance light scattering (RLS) imaging method to determine heparin is described based on the high light scattering emission power of the aggregation species of heparin with α, β, γ, δtetra(4-trimethylaminoniumphenyl)prophyrin (TAPP) in solution. By imaging the light scattering signals of the aggregation species, we proposed the method to determine the heparin with a detection range of 0.02-0.6μg/mL and the detection limit (3σ) of 1.3 ng/mL.
Determination of Gossypol in Trace Level by Flow Injection Analysis with Chemiluminescence Detection
2006, 17(1): 57-60
Abstract:
This work reports the single-molecule detection of gossypol by flow injection analysis with chemiluminescence method. The method is based on the reaction of luminol with ferricyanid in sodium hydroxide medium sensitized by gossypol. Under the optimum conditions, the CL intensity is proportional to the concentration of gossypol over the range of 1.11×10-17-2.78×10-16 mol/L in acid solution and 8.00×10-11-7.39×10-8 mol/L in neutral solution with correlation coefficients 0.9983 and 0.9905, respectively. The detection limits is 1.60×l0-18 mol/L (S/N=3). The proposed method has been applied for the determination of the gossypol in cottonseeds and pharmaceutical formulations with satisfactory results.
This work reports the single-molecule detection of gossypol by flow injection analysis with chemiluminescence method. The method is based on the reaction of luminol with ferricyanid in sodium hydroxide medium sensitized by gossypol. Under the optimum conditions, the CL intensity is proportional to the concentration of gossypol over the range of 1.11×10-17-2.78×10-16 mol/L in acid solution and 8.00×10-11-7.39×10-8 mol/L in neutral solution with correlation coefficients 0.9983 and 0.9905, respectively. The detection limits is 1.60×l0-18 mol/L (S/N=3). The proposed method has been applied for the determination of the gossypol in cottonseeds and pharmaceutical formulations with satisfactory results.
2006, 17(1): 61-64
Abstract:
The Pd-modified Cu (Pd/Cu) electrodes for nitrate reduction were prepared using electro-deposition method at different potentials. Compared with other different electrodes so far studied in our work (Cu, Sn/Cu and Pd/Ti electrode) using cyclic voltammetry method, Pd/Cu electrode showed the highest electrocatalytic capacity of nitrate reduction. It was found that at more negative electrode potential the smaller Pd particles formed on the Cu electrode, which was beneficial to the nitrate reduction. With increasing deposition amount of Pd, the capacity of nitrate reduction increased. Too rich Pd, however, has a negative influence on the capacity of nitrate reduction. In our study, the maximum nitrate reduction current was 2.07 mA/cm2, when electrodeposition potential of Pd was -0.3 V and deposition amount was 0.9 C.
The Pd-modified Cu (Pd/Cu) electrodes for nitrate reduction were prepared using electro-deposition method at different potentials. Compared with other different electrodes so far studied in our work (Cu, Sn/Cu and Pd/Ti electrode) using cyclic voltammetry method, Pd/Cu electrode showed the highest electrocatalytic capacity of nitrate reduction. It was found that at more negative electrode potential the smaller Pd particles formed on the Cu electrode, which was beneficial to the nitrate reduction. With increasing deposition amount of Pd, the capacity of nitrate reduction increased. Too rich Pd, however, has a negative influence on the capacity of nitrate reduction. In our study, the maximum nitrate reduction current was 2.07 mA/cm2, when electrodeposition potential of Pd was -0.3 V and deposition amount was 0.9 C.
2006, 17(1): 65-68
Abstract:
The non-covalent complexes between lappaconitine (LA) and β-cyclodextrin (β-CD) have been detected and characterized by electrospray ionization combined with ion trap tandem mass spectrometry (ESI-MSn). The experimental results showed that only 1:1 non-covalent complex can be formed in different starting molar ratios of LA to β-CD. Furthermore, the diagnostic fragmentation of the β-CD-LA complex, with a significant contribution of covalent fragmentation of LA leaving the N-acetyl anthranoyl (AN) moiety inserted to β-CD, provided the convincing evidence for the formation of non-covalent complex between LA and β-CD and the cite of LA molecule included to cavity of β-CD assigned to AN residue.
The non-covalent complexes between lappaconitine (LA) and β-cyclodextrin (β-CD) have been detected and characterized by electrospray ionization combined with ion trap tandem mass spectrometry (ESI-MSn). The experimental results showed that only 1:1 non-covalent complex can be formed in different starting molar ratios of LA to β-CD. Furthermore, the diagnostic fragmentation of the β-CD-LA complex, with a significant contribution of covalent fragmentation of LA leaving the N-acetyl anthranoyl (AN) moiety inserted to β-CD, provided the convincing evidence for the formation of non-covalent complex between LA and β-CD and the cite of LA molecule included to cavity of β-CD assigned to AN residue.
2006, 17(1): 69-72
Abstract:
A new europium complex is descried as a time-resolved luminescence-based sensor for fluoride anion. The sensor is selective even in the presence of intensive background fluorescence.
A new europium complex is descried as a time-resolved luminescence-based sensor for fluoride anion. The sensor is selective even in the presence of intensive background fluorescence.
2006, 17(1): 73-76
Abstract:
Resistive-type film humidity sensors were prepared with a silicone-containing polyelectrolyte (Si-PE) and their humidity sensitive properties have been investigated. The sensors so obtained show high sensitivity to humidity variation over a wide range of RH (20-96%).In addition, they exhibit high reversibility, quick response and well long-term stability.
Resistive-type film humidity sensors were prepared with a silicone-containing polyelectrolyte (Si-PE) and their humidity sensitive properties have been investigated. The sensors so obtained show high sensitivity to humidity variation over a wide range of RH (20-96%).In addition, they exhibit high reversibility, quick response and well long-term stability.
2006, 17(1): 77-80
Abstract:
A novel oscillating chemical reaction using ninhydrin as a single organic substrate was represented in this paper. It distinguished from the classically catalyzed BZ oscillating chemical reaction due to there was no active methene (CH2=) and/or enol structure in the ninhydrin molecule, which served as single organic substrate. This suggested that the substrates used in catalyzed BZ reaction were not always the organic compounds containing active methene (CH2=) and/or enol structure and bromination process in this kind of catalyzed chemical oscillating reaction was not also necessary.
A novel oscillating chemical reaction using ninhydrin as a single organic substrate was represented in this paper. It distinguished from the classically catalyzed BZ oscillating chemical reaction due to there was no active methene (CH2=) and/or enol structure in the ninhydrin molecule, which served as single organic substrate. This suggested that the substrates used in catalyzed BZ reaction were not always the organic compounds containing active methene (CH2=) and/or enol structure and bromination process in this kind of catalyzed chemical oscillating reaction was not also necessary.
2006, 17(1): 81-84
Abstract:
A non-polar organic dye, E, E-l, 4-bis[4'-(N, N-dibutylamino)styryl]-2, 5-dimethoxybenzene (DBASDMB), has been synthesized and characterized, and its structure has been determined. Pumped with a 200fs pulse this dye showed the up-conversion laser properties. The influences of various organic solvents and different pumping wavelength on the laser properties have been demonstrated.
A non-polar organic dye, E, E-l, 4-bis[4'-(N, N-dibutylamino)styryl]-2, 5-dimethoxybenzene (DBASDMB), has been synthesized and characterized, and its structure has been determined. Pumped with a 200fs pulse this dye showed the up-conversion laser properties. The influences of various organic solvents and different pumping wavelength on the laser properties have been demonstrated.
2006, 17(1): 85-88
Abstract:
Highly water soluble esters of scutellarin with variable molecular weight polyethylene glycol (PEG) were prepared via PEGylation. The physicochemical properties and the stabilities under different conditions were investigated. By PEG modification, the greatly increased water solubility and desirable partition coefficient of scutellarin were obtained, and the results showed that these conjugates were potential prodrugs for the oral delivery of scutellarin.
Highly water soluble esters of scutellarin with variable molecular weight polyethylene glycol (PEG) were prepared via PEGylation. The physicochemical properties and the stabilities under different conditions were investigated. By PEG modification, the greatly increased water solubility and desirable partition coefficient of scutellarin were obtained, and the results showed that these conjugates were potential prodrugs for the oral delivery of scutellarin.
2006, 17(1): 89-92
Abstract:
The kinetic study on the hydrolysis reaction of bis(4-nitrophenyl) phosphate (BNPP) catalyzed by Tb-BDBPH system(2:1) was carried out in 50% ethanol solution (pH 7.0-10.0) at 35℃ with I=0.10NaNO3. The second-order rate constant kBNPP, 2.3×10-3 (mol-1L S-1), was determined. The dinuclear monohydroxo species, L-2Tb-OH, is kinetically mainly active species.The hydrolysis rate of BNPP by the complex is increased almost 2.6 million-fold compared with the background hydroxide rate at the same condition.
The kinetic study on the hydrolysis reaction of bis(4-nitrophenyl) phosphate (BNPP) catalyzed by Tb-BDBPH system(2:1) was carried out in 50% ethanol solution (pH 7.0-10.0) at 35℃ with I=0.10NaNO3. The second-order rate constant kBNPP, 2.3×10-3 (mol-1L S-1), was determined. The dinuclear monohydroxo species, L-2Tb-OH, is kinetically mainly active species.The hydrolysis rate of BNPP by the complex is increased almost 2.6 million-fold compared with the background hydroxide rate at the same condition.
2006, 17(1): 93-96
Abstract:
A new cucurbit[6]uril bridged binuclear complex {[Gd(H2O)6]2[Q6(H2O)]}Cl6·4H2O, where Q6 represents cucurbit[6]uril, has been synthesized and characterized by X-ray diffraction.The crystal structure shows that the complex has an extended cucurbit[6]uril-bridged structure consisting of two gadolinium(Ⅲ) ions, in which each gadolinium(Ⅲ) ion is coordinated with two neighboring carbonylic oxygen atoms of Q6 and six oxygen atoms of water molecules that leans toward one side of the portal. One disordered guest water molecule resides in the Q6 molecule cavity and occupies two different positions. Hydrogen bonds assemble the complex to three-dimensional supramolecular structure.
A new cucurbit[6]uril bridged binuclear complex {[Gd(H2O)6]2[Q6(H2O)]}Cl6·4H2O, where Q6 represents cucurbit[6]uril, has been synthesized and characterized by X-ray diffraction.The crystal structure shows that the complex has an extended cucurbit[6]uril-bridged structure consisting of two gadolinium(Ⅲ) ions, in which each gadolinium(Ⅲ) ion is coordinated with two neighboring carbonylic oxygen atoms of Q6 and six oxygen atoms of water molecules that leans toward one side of the portal. One disordered guest water molecule resides in the Q6 molecule cavity and occupies two different positions. Hydrogen bonds assemble the complex to three-dimensional supramolecular structure.
2006, 17(1): 97-100
Abstract:
The influence of sulfated polysaccharide (SPS) isolated from marine algae Sargassum fusiforme on the morphology and phase compositions of urinary crystal calcium oxalate was investigated in vitro by means of scanning electron microscopy and X-ray diffraction. SPS maybe is a potential inhibitor to CaOxa urinary stones by inhibiting the growth of calcium oxalate monohydrate (COM), preventing the aggregation of COM, and inducing the formation of calcium oxalate dihydrate (COD) crystals.
The influence of sulfated polysaccharide (SPS) isolated from marine algae Sargassum fusiforme on the morphology and phase compositions of urinary crystal calcium oxalate was investigated in vitro by means of scanning electron microscopy and X-ray diffraction. SPS maybe is a potential inhibitor to CaOxa urinary stones by inhibiting the growth of calcium oxalate monohydrate (COM), preventing the aggregation of COM, and inducing the formation of calcium oxalate dihydrate (COD) crystals.
2006, 17(1): 101-104
Abstract:
The lysozyme crystals were made by batch crystallization method and the distribution of aggregate in solution were measured by dynamic light scattering. The results showed that the dimension of aggregate increased with the increase of the concentration of lysozyme and NaC1, lysozyme molecules aggregated gradually in solution and finally arrived at balance each other.The higher the concentrations of lysozyme and NaC1 were, the faster the growth rate of (110) face was. The growth rates of lysozyme crystal were obtained by a Zeiss microscope, and the effective surface energy (α) of growing steps were calculated about 4.01×l0-8 J·cm-2 according to the model of multiple two-dimensional nucleation mechanism.
The lysozyme crystals were made by batch crystallization method and the distribution of aggregate in solution were measured by dynamic light scattering. The results showed that the dimension of aggregate increased with the increase of the concentration of lysozyme and NaC1, lysozyme molecules aggregated gradually in solution and finally arrived at balance each other.The higher the concentrations of lysozyme and NaC1 were, the faster the growth rate of (110) face was. The growth rates of lysozyme crystal were obtained by a Zeiss microscope, and the effective surface energy (α) of growing steps were calculated about 4.01×l0-8 J·cm-2 according to the model of multiple two-dimensional nucleation mechanism.
2006, 17(1): 105-108
Abstract:
The thermal behaviors of five proteins in hydrophobic interaction chromatography (HIC) were investigated in the temperature range from 0 to 50℃. The thermodynamic parameters (△H°, △S°, △Cp°and △G°) of these proteins in the process of retention and unfolding were determined.The existence of enthalpy and entropy convergence with temperature was confirmed. The differences of the isoentropic and isoenthalpic temperatures for protein unfolding in HIC system from the traditional solution were elucidated.
The thermal behaviors of five proteins in hydrophobic interaction chromatography (HIC) were investigated in the temperature range from 0 to 50℃. The thermodynamic parameters (△H°, △S°, △Cp°and △G°) of these proteins in the process of retention and unfolding were determined.The existence of enthalpy and entropy convergence with temperature was confirmed. The differences of the isoentropic and isoenthalpic temperatures for protein unfolding in HIC system from the traditional solution were elucidated.
2006, 17(1): 109-112
Abstract:
Uniform Ni-B amorphous alloys about 14 nm have been prepared on CNTs-A support, named Ni-B/CNTs-A. In comparison with the Ni-B/CNTs amorphous catalyst, Ni-B/CNTs-A showed higher nickel loading, determined by ICP and better catalytic activity and ethylene selectivity in the acetylene hydrogenation reaction.
Uniform Ni-B amorphous alloys about 14 nm have been prepared on CNTs-A support, named Ni-B/CNTs-A. In comparison with the Ni-B/CNTs amorphous catalyst, Ni-B/CNTs-A showed higher nickel loading, determined by ICP and better catalytic activity and ethylene selectivity in the acetylene hydrogenation reaction.
2006, 17(1): 113-116
Abstract:
The work described the synthesis and evaluation of PEI-g-comb-PEG-transferrin as a potential system for gene therapy in vitro. The MW of PEG was 10KDa, and PEI was 2KDa.Its structure was identified by NMR, FT-IR and TGA spectroscopy. MTT assay found that at concentration up to 4000 n mol/L of the polymer, cell viability was over 85%. The bio-character of polymer/DNA complex was characterized by agarose gel electrophoresis, ethidium bromide exclusion and zeta-potential assay. The polymer could retardate DNA at N/P ratio 3.0-3.5(mol/mol). The particle size of the polymer/DNA complex was less than 300 nm. Transfection efficiency of the complex was studied in COS7 and NT2 cell lines.
The work described the synthesis and evaluation of PEI-g-comb-PEG-transferrin as a potential system for gene therapy in vitro. The MW of PEG was 10KDa, and PEI was 2KDa.Its structure was identified by NMR, FT-IR and TGA spectroscopy. MTT assay found that at concentration up to 4000 n mol/L of the polymer, cell viability was over 85%. The bio-character of polymer/DNA complex was characterized by agarose gel electrophoresis, ethidium bromide exclusion and zeta-potential assay. The polymer could retardate DNA at N/P ratio 3.0-3.5(mol/mol). The particle size of the polymer/DNA complex was less than 300 nm. Transfection efficiency of the complex was studied in COS7 and NT2 cell lines.
2006, 17(1): 117-120
Abstract:
The random copolymer poly (1, 3-pentadiene-co-styrene) formed through cationic copolymerization using the triethylamine hydrochloride and hydrous aluminium chloride (Et3NHC1-A1C13) room temperature ionic liquid as initiating agent in toluene was analyzed using IR spectra in conjunction with gel permeation chromatography (GPC). The room temperature ionic liquid was found to have high initiatic activity for copolymerization.
The random copolymer poly (1, 3-pentadiene-co-styrene) formed through cationic copolymerization using the triethylamine hydrochloride and hydrous aluminium chloride (Et3NHC1-A1C13) room temperature ionic liquid as initiating agent in toluene was analyzed using IR spectra in conjunction with gel permeation chromatography (GPC). The room temperature ionic liquid was found to have high initiatic activity for copolymerization.
2006, 17(1): 121-124
Abstract:
The synthetic parameters were changed to explore the formation mechanism of the oxygen-containing groups on the surfaces of the hypercrosslinked polymers. The FT-IR spectra and the Boehm titration were used to characterize the surface chemistry of the synthesized polymers. The GC-MS was applied to analyze nitrobenzene which was the solvent in the reaction.The functionalities such as carbonyls and phenols were formed through the oxidation of residual chloromethyl groups by nitrobenzene and the carboxylic groups were formed through further oxidation by oxygen. The nitrobenzene was deoxidized to nitrosobenzene and further to aniline.
The synthetic parameters were changed to explore the formation mechanism of the oxygen-containing groups on the surfaces of the hypercrosslinked polymers. The FT-IR spectra and the Boehm titration were used to characterize the surface chemistry of the synthesized polymers. The GC-MS was applied to analyze nitrobenzene which was the solvent in the reaction.The functionalities such as carbonyls and phenols were formed through the oxidation of residual chloromethyl groups by nitrobenzene and the carboxylic groups were formed through further oxidation by oxygen. The nitrobenzene was deoxidized to nitrosobenzene and further to aniline.
2006, 17(1): 125-128
Abstract:
The synthesis and characterization of hyperbranched polyester (HBP) with different molecular weight are studied. The effect of HBP on the modification of epoxy resins cured with anhydride is mainly discussed. The characteristics of HBP and the morphologies of cured system are determined by nuclear magnetic resonance spectroscopy (NMR), gel permeation chromatography (GPC) and scanning electron microscope (SEM). The impact strength of cured system is detected and Fourier transform infrared (FTIR) measurements were used to pursue the curing process. The investigation shows that HBP can improve the toughness by forming copolymer networks between epoxy resins, HBP and anhydride. Moreover, when the molecular weight of HBP is 1342g/mol the toughening effect is the best, and the changes of toughness are small with the increase of molecular weight of HBP to 3500 g/mol.
The synthesis and characterization of hyperbranched polyester (HBP) with different molecular weight are studied. The effect of HBP on the modification of epoxy resins cured with anhydride is mainly discussed. The characteristics of HBP and the morphologies of cured system are determined by nuclear magnetic resonance spectroscopy (NMR), gel permeation chromatography (GPC) and scanning electron microscope (SEM). The impact strength of cured system is detected and Fourier transform infrared (FTIR) measurements were used to pursue the curing process. The investigation shows that HBP can improve the toughness by forming copolymer networks between epoxy resins, HBP and anhydride. Moreover, when the molecular weight of HBP is 1342g/mol the toughening effect is the best, and the changes of toughness are small with the increase of molecular weight of HBP to 3500 g/mol.
2006, 17(1): 129-132
Abstract:
The hydrophilic, macroporous and beaded ternary copolymer of glycidyl methacrylate (GMA)/methacrylamide(MA)/N, N'-methylene-bis(acrylamide)(MBAA)was synthesized using the industrial agents by inverse suspension polymerization. The apparent activity of the immobilized penicillin G acylase reached 1096 IU/g for hydrolysis penicillin G on the beads with diameter of 0.11-0.13 mm, and it changed hardly after 50 cycles. It can be expected to be a good potential in industrial application.
The hydrophilic, macroporous and beaded ternary copolymer of glycidyl methacrylate (GMA)/methacrylamide(MA)/N, N'-methylene-bis(acrylamide)(MBAA)was synthesized using the industrial agents by inverse suspension polymerization. The apparent activity of the immobilized penicillin G acylase reached 1096 IU/g for hydrolysis penicillin G on the beads with diameter of 0.11-0.13 mm, and it changed hardly after 50 cycles. It can be expected to be a good potential in industrial application.
2006, 17(1): 133-136
Abstract:
In this paper, ethylenebisformamide was synthesized and used as a novel plasticizer for cornstarch to prepare thermoplastic starch (TPS). FT-IR expressed that ethylenebisformamide formed stronger and stable hydrogen bond with starch molecules compared to the native cornstarch.X-ray diffraction (XRD) showed that the typical A-style crystallinity in the native starch has been destructed. By scanning electron microscope (SEM) native cornstarch granules were proved to transfer to a homogeneous system. After being stored for one week at RH=33%, the mechanical properties of EPTPS was also studied. The elongation reached to 264% utmost. As a novel plasticizer, ethylenebisformamide would be practical to extend TPS application scopes.
In this paper, ethylenebisformamide was synthesized and used as a novel plasticizer for cornstarch to prepare thermoplastic starch (TPS). FT-IR expressed that ethylenebisformamide formed stronger and stable hydrogen bond with starch molecules compared to the native cornstarch.X-ray diffraction (XRD) showed that the typical A-style crystallinity in the native starch has been destructed. By scanning electron microscope (SEM) native cornstarch granules were proved to transfer to a homogeneous system. After being stored for one week at RH=33%, the mechanical properties of EPTPS was also studied. The elongation reached to 264% utmost. As a novel plasticizer, ethylenebisformamide would be practical to extend TPS application scopes.
2006, 17(1): 137-139
Abstract:
A new six-membered cyclic carbonate monomer, 5-allyloxytrimethylene carbonate (ATMC), was synthesized starting from glycerol, and the corresponding polycarbonates, poly(5-allyloxytrimethylene carbonate)(PATMC) were further synthesized by ring-opening polymerization in bulk at 150℃ using stannous octanoate as an initiator. The structures of the monomer and the polymers were confirmed by IR, 1H-NMR, 13C-NMR, and GPC analysis.
A new six-membered cyclic carbonate monomer, 5-allyloxytrimethylene carbonate (ATMC), was synthesized starting from glycerol, and the corresponding polycarbonates, poly(5-allyloxytrimethylene carbonate)(PATMC) were further synthesized by ring-opening polymerization in bulk at 150℃ using stannous octanoate as an initiator. The structures of the monomer and the polymers were confirmed by IR, 1H-NMR, 13C-NMR, and GPC analysis.
2006, 17(1): 140-142
Abstract:
A novel diacid chloride, 2-(4-chlorocarboxyphenyl)-4-[3, 5-dimethyl-4-(4-chlorocarbo-xylphenoxy)phenyl]-2, 3-phlhalazin-l-one 2, was synthesized and used for the preparation of polyarylates with inherent viscosities of 0.25-0.37dL·g-1, The glass tramsition temperatures of polyarylates were in the range of 217-272℃. The temperatures at 10% weight loss of polyarylates were found to be in the range of 434-464℃ in nitrogen atmosphere and their structure was confirmed by FTIR and 1H NMR. The amorphous polyarylates exhibited excellent solubility in a variety of solvents such as NMP, DMAc, DMF and chloroform.
A novel diacid chloride, 2-(4-chlorocarboxyphenyl)-4-[3, 5-dimethyl-4-(4-chlorocarbo-xylphenoxy)phenyl]-2, 3-phlhalazin-l-one 2, was synthesized and used for the preparation of polyarylates with inherent viscosities of 0.25-0.37dL·g-1, The glass tramsition temperatures of polyarylates were in the range of 217-272℃. The temperatures at 10% weight loss of polyarylates were found to be in the range of 434-464℃ in nitrogen atmosphere and their structure was confirmed by FTIR and 1H NMR. The amorphous polyarylates exhibited excellent solubility in a variety of solvents such as NMP, DMAc, DMF and chloroform.
