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2009 Volume 20 Issue 11
2009, 20(11): 1271-1274
doi: 10.1016/j.cclet.2009.05.022
Abstract:
Two novel fluorescent calix[4]arene derivatives (1a) and (1b) with benzoxazole or benzothiazole units in 1,3-alternate conformation have been synthesized and characterized by IR,1H NMR,13C NMR and MS. Their complexation properties to different heavy and transition metal ions have been studied by UV-vis spectroscopy and fluorescence spectrometer. Compounds (1a) and (1b) show selective recognition to Fe3+and Cr3+.
Two novel fluorescent calix[4]arene derivatives (1a) and (1b) with benzoxazole or benzothiazole units in 1,3-alternate conformation have been synthesized and characterized by IR,1H NMR,13C NMR and MS. Their complexation properties to different heavy and transition metal ions have been studied by UV-vis spectroscopy and fluorescence spectrometer. Compounds (1a) and (1b) show selective recognition to Fe3+and Cr3+.
2009, 20(11): 1275-1278
doi: 10.1016/j.cclet.2009.06.024
Abstract:
A series of aromatic aldehydes are turned in to 3,3,6,6-tetramethyl-9-aryl-1,8-dioxooctahydroxanthene derivatives using trichloroisocyanuric acid (TCCA) as the catalyst.
A series of aromatic aldehydes are turned in to 3,3,6,6-tetramethyl-9-aryl-1,8-dioxooctahydroxanthene derivatives using trichloroisocyanuric acid (TCCA) as the catalyst.
2009, 20(11): 1279-1282
doi: 10.1016/j.cclet.2009.06.006
Abstract:
New two-photon absorption dyes including benzophenone parts, p-N,N-diphenylamino-p'-phenacylstilbene (C1), 4,4-di-(4-benzoylstyrene)yltriphenylamine (C2) and 4,4',4"-tri(4-benzoylstyrene)yltriphenylamine (C3), were synthesized and characterizedby 1H NMR and elemental analysis. The ratio of the molar extinction coefficients of compounds was approximately equal to the ratio of the branch amount of the compounds, namely, C1:C2:C3 was 1:2:3. Extremely high fluorescence quantum yields were detected for these compounds. These molecules exhibited obvious two-photon upconcerted fluorescence as excited by 800 nm Ti:sapphire femtosecond laser.
New two-photon absorption dyes including benzophenone parts, p-N,N-diphenylamino-p'-phenacylstilbene (C1), 4,4-di-(4-benzoylstyrene)yltriphenylamine (C2) and 4,4',4"-tri(4-benzoylstyrene)yltriphenylamine (C3), were synthesized and characterizedby 1H NMR and elemental analysis. The ratio of the molar extinction coefficients of compounds was approximately equal to the ratio of the branch amount of the compounds, namely, C1:C2:C3 was 1:2:3. Extremely high fluorescence quantum yields were detected for these compounds. These molecules exhibited obvious two-photon upconcerted fluorescence as excited by 800 nm Ti:sapphire femtosecond laser.
2009, 20(11): 1283-1286
doi: 10.1016/j.cclet.2009.04.038
Abstract:
Two series of novel tolane-type liquid crystals (LCs) comprising of hydrogen-bonded organic acids were synthesized. The formation of dimerized H-bond LCs was confirmed by IR spectroscopy, and mesomorphic properties of the LCs were investigated by differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). It was found that the end groups of the liquid crystals as well as the unsaturated rigid core had effect on the mesomorphic properties.
Two series of novel tolane-type liquid crystals (LCs) comprising of hydrogen-bonded organic acids were synthesized. The formation of dimerized H-bond LCs was confirmed by IR spectroscopy, and mesomorphic properties of the LCs were investigated by differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). It was found that the end groups of the liquid crystals as well as the unsaturated rigid core had effect on the mesomorphic properties.
2009, 20(11): 1287-1290
doi: 10.1016/j.cclet.2009.05.028
Abstract:
A number of novel strobilurin analogues containing substituted N-phenylpyrimidin-2-amines were synthesized. The structures of these new compounds were confirmed by 1H NMR, IR and elemental analysis. Biological evaluation in the greenhouse showed several compounds have good fungicidal activities at 25 mg/L.
A number of novel strobilurin analogues containing substituted N-phenylpyrimidin-2-amines were synthesized. The structures of these new compounds were confirmed by 1H NMR, IR and elemental analysis. Biological evaluation in the greenhouse showed several compounds have good fungicidal activities at 25 mg/L.
2009, 20(11): 1291-1295
doi: 10.1016/j.cclet.2009.06.009
Abstract:
Series of new 2-aryl-6-styryl-2,3-dihydropyridin-4(1H)-one derivatives were synthesized in acceptable to good yields by treatment of the curcuminoids with aqueous ammonia, the mechanism was proposed. By modification of the primary products, total 13 new compounds were otained. The structures of all products were elucidated by spectroscopy analysis including HR-MS,1HNMR and 13C NMR.
Series of new 2-aryl-6-styryl-2,3-dihydropyridin-4(1H)-one derivatives were synthesized in acceptable to good yields by treatment of the curcuminoids with aqueous ammonia, the mechanism was proposed. By modification of the primary products, total 13 new compounds were otained. The structures of all products were elucidated by spectroscopy analysis including HR-MS,1HNMR and 13C NMR.
2009, 20(11): 1296-1298
doi: 10.1016/j.cclet.2009.06.025
Abstract:
A Fe-complexed dye containing crosslinkable polyamine groups was synthesized through diazotization and coupling reaction,chlorination, amination and metallization. The structure of the Fe-complexed crosslinking dye was characterized by FT-IR and Atomic Absorption Spectroscopic techniques. The dyeing and light fastness properties of the Fe-complex on silk and wool were tested, and the results showed that the novel Fe-complex exhibited both high fixation and good light fastness.
A Fe-complexed dye containing crosslinkable polyamine groups was synthesized through diazotization and coupling reaction,chlorination, amination and metallization. The structure of the Fe-complexed crosslinking dye was characterized by FT-IR and Atomic Absorption Spectroscopic techniques. The dyeing and light fastness properties of the Fe-complex on silk and wool were tested, and the results showed that the novel Fe-complex exhibited both high fixation and good light fastness.
2009, 20(11): 1299-1302
doi: 10.1016/j.cclet.2009.06.014
Abstract:
Oxonium ylide intermediates generated from α-diazocarbonyl compounds and water were trapped by Zn(Ⅱ)-activated adicarbonyl compounds. The reaction gave α,β-dihydroxyl acid derivatives in moderate yield.
Oxonium ylide intermediates generated from α-diazocarbonyl compounds and water were trapped by Zn(Ⅱ)-activated adicarbonyl compounds. The reaction gave α,β-dihydroxyl acid derivatives in moderate yield.
2009, 20(11): 1303-1306
doi: 10.1016/j.cclet.2009.05.010
Abstract:
Two series of novel cholesteryl-containing H-bonded liquid crystals were prepared through facile self-assembly between cholesteryl isonicotinate (proton acceptor) exhibiting a monotropic cholesteric phase, and the 4-alkoxy-benzoic acid or 4-alkoxy cinnamic acid (proton donor). It was found that the increase of the conjugate length as well as the terminal length can contribute to enhance the interaction of molecules and thus significantly influenced the thermal behaviors of H-bonded LCs. The cholesteric reflection spectra of the induced mesogenic complexes were located in the visible region with the color tuneable thermo-sensitivity,which could be used for display application.
Two series of novel cholesteryl-containing H-bonded liquid crystals were prepared through facile self-assembly between cholesteryl isonicotinate (proton acceptor) exhibiting a monotropic cholesteric phase, and the 4-alkoxy-benzoic acid or 4-alkoxy cinnamic acid (proton donor). It was found that the increase of the conjugate length as well as the terminal length can contribute to enhance the interaction of molecules and thus significantly influenced the thermal behaviors of H-bonded LCs. The cholesteric reflection spectra of the induced mesogenic complexes were located in the visible region with the color tuneable thermo-sensitivity,which could be used for display application.
2009, 20(11): 1307-1310
doi: 10.1016/j.cclet.2009.06.028
Abstract:
Sixteen new derivatives of spiromesifen were synthesized from 3-(2,4,6-trimethylphenyl)-4-hydroxy-△3-dihydrofuran-2-one.Their bioactivities against diamondbackmoth (Plutella xylostella) and spider mites (Tetranychus cinnabarinus) were also evaluated.The structures of these derivatives were confirmed by 1H NMR, MS.
Sixteen new derivatives of spiromesifen were synthesized from 3-(2,4,6-trimethylphenyl)-4-hydroxy-△3-dihydrofuran-2-one.Their bioactivities against diamondbackmoth (Plutella xylostella) and spider mites (Tetranychus cinnabarinus) were also evaluated.The structures of these derivatives were confirmed by 1H NMR, MS.
2009, 20(11): 1311-1314
doi: 10.1016/j.cclet.2009.06.020
Abstract:
Zinc chloride is an efficient and safe catalyst in the [3+2] cycloaddition reaction of organic nitriles with sodium azide in solventless condition. The corresponding 5-substituted 1H tetrazoles were obtained under mild conditions. This method can overcome disadvantages such as:the use of toxic metals and expensive reagents, drastic reaction conditions, water sensitivity and the presence of dangerous hydrazoic acid.
Zinc chloride is an efficient and safe catalyst in the [3+2] cycloaddition reaction of organic nitriles with sodium azide in solventless condition. The corresponding 5-substituted 1H tetrazoles were obtained under mild conditions. This method can overcome disadvantages such as:the use of toxic metals and expensive reagents, drastic reaction conditions, water sensitivity and the presence of dangerous hydrazoic acid.
Endonuclease-rolling circle amplification-based method for sensitive analysis of DNA-binding protein
2009, 20(11): 1315-1318
doi: 10.1016/j.cclet.2009.06.008
Abstract:
A sensitive approach for the qualitative detection of DNA-binding protein on the microarray was developed. DNA complexes in which a partial duplex region is formed from a biotin-primer and a circle single strand DNA (ssDNA) were spotted on a microarray.The endonuclease recognition site (ERS) and the DNA-binding sites (DBS) were arranged side by side within the duplex region.The working principle of the detection system is described as follows:when the DNA-binding protein capture the DBS, the endonuclease could not attach to the ERS, and the immobilized primer in the DNA complex could be extended along the circle ssDNA by rolling circle amplification (RCA). When no protein protects the DBS, the ERS could be attacked by the endonuclease and subsequently no rolling circle amplification occurs. Thereby we can detect the sequence specific DNA-binding activity with high-sensitivity due to the signal amplification of RCA.
A sensitive approach for the qualitative detection of DNA-binding protein on the microarray was developed. DNA complexes in which a partial duplex region is formed from a biotin-primer and a circle single strand DNA (ssDNA) were spotted on a microarray.The endonuclease recognition site (ERS) and the DNA-binding sites (DBS) were arranged side by side within the duplex region.The working principle of the detection system is described as follows:when the DNA-binding protein capture the DBS, the endonuclease could not attach to the ERS, and the immobilized primer in the DNA complex could be extended along the circle ssDNA by rolling circle amplification (RCA). When no protein protects the DBS, the ERS could be attacked by the endonuclease and subsequently no rolling circle amplification occurs. Thereby we can detect the sequence specific DNA-binding activity with high-sensitivity due to the signal amplification of RCA.
2009, 20(11): 1319-1320
doi: 10.1016/j.cclet.2009.06.003
Abstract:
A new alkaloid was isolated from the bulbs of Lycoris aurea (L'Herit.) Herb. Its structure was established as 3-o-ethyltazettinol through chemical and spectroscopic studies including 2D NMR.
A new alkaloid was isolated from the bulbs of Lycoris aurea (L'Herit.) Herb. Its structure was established as 3-o-ethyltazettinol through chemical and spectroscopic studies including 2D NMR.
2009, 20(11): 1321-1323
doi: 10.1016/j.cclet.2009.06.010
Abstract:
Phytochemical study on the BuOH-soluble fraction of the stem bark of Populus davidiana resulted in the isolation of a new salicin derivative (1), named davidianoside. The structure was elucidated on the basis of extensive physicochemical and spectroscopic analyses.
Phytochemical study on the BuOH-soluble fraction of the stem bark of Populus davidiana resulted in the isolation of a new salicin derivative (1), named davidianoside. The structure was elucidated on the basis of extensive physicochemical and spectroscopic analyses.
2009, 20(11): 1324-1326
doi: 10.1016/j.cclet.2009.05.021
Abstract:
A novel polyketide pigment (1) with the 4',10-coupled linkage between 1-naphthalenol and 1,4-anthraquinone, named rufoolivacin B together with the known analog rufoolivacin (2), has been isolated from the fruiting bodies of the Chinese toadstool Cortinarius rufo-olivaceus (basidiomycetes). Their structures were characterized by means of analysis of spectroscopic methods, including 2D-NMR experiments and HR-ESI-MS.
A novel polyketide pigment (1) with the 4',10-coupled linkage between 1-naphthalenol and 1,4-anthraquinone, named rufoolivacin B together with the known analog rufoolivacin (2), has been isolated from the fruiting bodies of the Chinese toadstool Cortinarius rufo-olivaceus (basidiomycetes). Their structures were characterized by means of analysis of spectroscopic methods, including 2D-NMR experiments and HR-ESI-MS.
2009, 20(11): 1327-1330
doi: 10.1016/j.cclet.2009.06.005
Abstract:
A new neophysalin, named 5α-hydroxy-25,27-dihydro-4,7-didehydro-7-deoxyneophysalin A(1), along with three other known neophysalins (2-4) were isolated from the calyxes of Physalis alkekengi L. var. francheti (Mast.) Makino. The structure of 1 was determined by means of 1D and 2D NMR, UV, IR and mass spectra. Compound 1 displayed potent cytotoxicities in vitro against PC-3 and LNCaP cell lines.
A new neophysalin, named 5α-hydroxy-25,27-dihydro-4,7-didehydro-7-deoxyneophysalin A(1), along with three other known neophysalins (2-4) were isolated from the calyxes of Physalis alkekengi L. var. francheti (Mast.) Makino. The structure of 1 was determined by means of 1D and 2D NMR, UV, IR and mass spectra. Compound 1 displayed potent cytotoxicities in vitro against PC-3 and LNCaP cell lines.
2009, 20(11): 1331-1334
doi: 10.1016/j.cclet.2009.07.002
Abstract:
A new compound, kudinoside LZ2 (1), was isolated from the leaves of Ilex kudincha. Its structure was elucidated by the combination of one- and two-dimensional NMR analysis, HR-ESI-MS, CD spectrum measurement and chemical evidences.
A new compound, kudinoside LZ2 (1), was isolated from the leaves of Ilex kudincha. Its structure was elucidated by the combination of one- and two-dimensional NMR analysis, HR-ESI-MS, CD spectrum measurement and chemical evidences.
2009, 20(11): 1335-1338
doi: 10.1016/j.cclet.2009.06.032
Abstract:
Three compounds were isolated from the tissue culture cells of Daphne giraldii cullus, their structures were identified as daphneolone (1), S-(+)-1-(4-hydroxy-3-methoxyphenyl)-3-hydroxy-5-phenyl-1-pentanone (2), S-(+)-1-(4-methoxyphenyl)-3- hydroxy-5-phenyl-1-pentanone (3), and among them, 2 was a new compound, 3 was a novel natural product.
Three compounds were isolated from the tissue culture cells of Daphne giraldii cullus, their structures were identified as daphneolone (1), S-(+)-1-(4-hydroxy-3-methoxyphenyl)-3-hydroxy-5-phenyl-1-pentanone (2), S-(+)-1-(4-methoxyphenyl)-3- hydroxy-5-phenyl-1-pentanone (3), and among them, 2 was a new compound, 3 was a novel natural product.
2009, 20(11): 1339-1341
doi: 10.1016/j.cclet.2009.07.001
Abstract:
A new macrolide glycoside, cuneataside F was isolated from the n-butanol extract of the stem of Sargentodoxa cuneata.The structure was elucidated on the basis of extensive 1D and 2D NMR as well as HRESI-MS spectroscopic analysis.
A new macrolide glycoside, cuneataside F was isolated from the n-butanol extract of the stem of Sargentodoxa cuneata.The structure was elucidated on the basis of extensive 1D and 2D NMR as well as HRESI-MS spectroscopic analysis.
2009, 20(11): 1342-1344
doi: 10.1016/j.cclet.2009.05.023
Abstract:
Two new isomeric compounds f rare acyclic C13-norisoprenoids, along with two known lignans sauchinone and licarin A, were isolated from the herb of Saururus chinensis (Lour.) Baill. Their structures were elucidated on the basis of spectral analysis.
Two new isomeric compounds f rare acyclic C13-norisoprenoids, along with two known lignans sauchinone and licarin A, were isolated from the herb of Saururus chinensis (Lour.) Baill. Their structures were elucidated on the basis of spectral analysis.
2009, 20(11): 1345-1347
doi: 10.1016/j.cclet.2009.05.011
Abstract:
Click chemistry was applied to immobilize L-proline derivative onto azide-modified silica gel to give a novel chiral stationary phase (denoted as click-CSP) for ligand exchange chromatography. The developed protocol combines the benefits of operational simplicity, exceptionally mild conditions and high surface loadings. The enantioselectivity α of some DL-amino acids on the click- CSP were found to be in the range from 1.13 to 3.46. The chromatographic resolutions of some DL-amino acids and the stability study firmly illustrate the potential of click chemistry for preparation chiral stationary phase for ligand exchange chromatography.
Click chemistry was applied to immobilize L-proline derivative onto azide-modified silica gel to give a novel chiral stationary phase (denoted as click-CSP) for ligand exchange chromatography. The developed protocol combines the benefits of operational simplicity, exceptionally mild conditions and high surface loadings. The enantioselectivity α of some DL-amino acids on the click- CSP were found to be in the range from 1.13 to 3.46. The chromatographic resolutions of some DL-amino acids and the stability study firmly illustrate the potential of click chemistry for preparation chiral stationary phase for ligand exchange chromatography.
2009, 20(11): 1348-1352
doi: 10.1016/j.cclet.2009.05.013
Abstract:
In situ melt polycondensation was proposed to prepare biodegradable aliphatic-aromatic copolyesters/nano-SiO 2hybrids based on terephthalic acid (TPA), poly(L-lactic acid) oligomer (OLLA), 1,4-butanediol (BDO) and nano-SiO 2. TEM and FT-IR characterizations confirmed that TPA, OLLA and BDO copolymerized to obtain biodegradable copolyesters, poly(butyleneterephthalate-co-lactate) (PBTL), and the abundant hydroxyl groups on the surface of nano-SiO 2 provided potential sites for In situ grafting with the simultaneous resulted PBTL. The nano-SiO 2 particles were chemically wrapped with PBTL to form PBTL/nano- SiO 2hybrids. Due to the good dispersion and interfacial adhesion of nano-SiO 2 particles with the copolyester matrix, the tensile strength and the Young's modulus increased from 5.4 and 5.6 MPa for neat PBTL to 16 and 390 MPa for PBTL/nano-SiO 2 hybrids with 5 wt.% nano-SiO 2, respectively. The mechanical properties of PBTL/nano-SiO 2 hybrids were substantially improved.
In situ melt polycondensation was proposed to prepare biodegradable aliphatic-aromatic copolyesters/nano-SiO 2hybrids based on terephthalic acid (TPA), poly(L-lactic acid) oligomer (OLLA), 1,4-butanediol (BDO) and nano-SiO 2. TEM and FT-IR characterizations confirmed that TPA, OLLA and BDO copolymerized to obtain biodegradable copolyesters, poly(butyleneterephthalate-co-lactate) (PBTL), and the abundant hydroxyl groups on the surface of nano-SiO 2 provided potential sites for In situ grafting with the simultaneous resulted PBTL. The nano-SiO 2 particles were chemically wrapped with PBTL to form PBTL/nano- SiO 2hybrids. Due to the good dispersion and interfacial adhesion of nano-SiO 2 particles with the copolyester matrix, the tensile strength and the Young's modulus increased from 5.4 and 5.6 MPa for neat PBTL to 16 and 390 MPa for PBTL/nano-SiO 2 hybrids with 5 wt.% nano-SiO 2, respectively. The mechanical properties of PBTL/nano-SiO 2 hybrids were substantially improved.
2009, 20(11): 1353-1356
doi: 10.1016/j.cclet.2009.06.007
Abstract:
Novel Y-shaped block copolymers of poly(ethylene glycol) and poly(N-isopropylacrylamide), PEG-b-(PNIPAM) 2, were successfully synthesized through atom transfer radical polymerization (ATRP). A difunctional macroinitiator was prepared by esterification of 2,2-dichloroacetyl chloride with poly(ethylene glycol) monomethyl ether (PEG). The copolymers were obtained via the ATRP of N-isopropylacrylamide (NIPAM) at 30 ℃with CuCl/Me6TREN as a catalyst system and DMF/H 2 O (v/v=3:1)n mixture as solvent. The resulting copolymers were characterized by gel permeation chromatography (GPC) and 1H NMR. These block copolymers show controllable molecular weights and narrow molecular weight distributions (PDI < 1.15). Their phase transition temperatures and the corresponding enthalpy changes in aqueous solution were measured by differential scanning calorimetry (DSC). As a result, the phase transition temperature of PEG 45-b-(PNIPAM 55) 2 is higher than that of PNIPAM, however,the corresponding enthalpy change is much lower, indicating the significant influence of the macromolecular composition and architecture on the phase transition.
Novel Y-shaped block copolymers of poly(ethylene glycol) and poly(N-isopropylacrylamide), PEG-b-(PNIPAM) 2, were successfully synthesized through atom transfer radical polymerization (ATRP). A difunctional macroinitiator was prepared by esterification of 2,2-dichloroacetyl chloride with poly(ethylene glycol) monomethyl ether (PEG). The copolymers were obtained via the ATRP of N-isopropylacrylamide (NIPAM) at 30 ℃with CuCl/Me6TREN as a catalyst system and DMF/H 2 O (v/v=3:1)n mixture as solvent. The resulting copolymers were characterized by gel permeation chromatography (GPC) and 1H NMR. These block copolymers show controllable molecular weights and narrow molecular weight distributions (PDI < 1.15). Their phase transition temperatures and the corresponding enthalpy changes in aqueous solution were measured by differential scanning calorimetry (DSC). As a result, the phase transition temperature of PEG 45-b-(PNIPAM 55) 2 is higher than that of PNIPAM, however,the corresponding enthalpy change is much lower, indicating the significant influence of the macromolecular composition and architecture on the phase transition.
2009, 20(11): 1357-1360
doi: 10.1016/j.cclet.2009.06.018
Abstract:
In this paper, we report the preparation of a new tertrahydrosalen-stabilized yttrium complex which was employed as an initiator-precursor for the polymerization of e-caprolactone (ε-CL) in the presence of NaBH 4 to give interesting hydroxytelechelic poly(ε-caprolactone) (PCL). The effect of [monomer]/[initiator] ([CL]/[I]), temperature and time on the polymerization was investigated. It was found that under the condition:[CL]/[I]=1200, 55 ℃, toluene:0.5 mL, ε-CL:0.5 mL, PCL with Mw=32,600 and PDI=1.47 was obtained.
In this paper, we report the preparation of a new tertrahydrosalen-stabilized yttrium complex which was employed as an initiator-precursor for the polymerization of e-caprolactone (ε-CL) in the presence of NaBH 4 to give interesting hydroxytelechelic poly(ε-caprolactone) (PCL). The effect of [monomer]/[initiator] ([CL]/[I]), temperature and time on the polymerization was investigated. It was found that under the condition:[CL]/[I]=1200, 55 ℃, toluene:0.5 mL, ε-CL:0.5 mL, PCL with Mw=32,600 and PDI=1.47 was obtained.
2009, 20(11): 1361-1365
doi: 10.1016/j.cclet.2009.06.011
Abstract:
Hydrophobically associative polyacrylamide (HAPAM) were prepared in aqueous solution by radical copolymerization of novel cationic surface-active monomer, dimethylhexadecyl(3-acrylamidopropyl)ammonium bromide (DMHAB), with acrylamide (AM)in the presence of DMHAB/CTAB mixed micelles. The length of hydrophobic microblock (NH) in HAPAM is controlled by the molar fraction of DMHAB in mixed micelles, which can be mediated by the ratio of CTAB to DMHAB. The results of steady-state fluorescence probe and viscometry experiments showed the ability of HAPAM association was determined by the length of the hydrophobic microblock. HAPAM with tunable association ability are promising materials for thickening agent.
Hydrophobically associative polyacrylamide (HAPAM) were prepared in aqueous solution by radical copolymerization of novel cationic surface-active monomer, dimethylhexadecyl(3-acrylamidopropyl)ammonium bromide (DMHAB), with acrylamide (AM)in the presence of DMHAB/CTAB mixed micelles. The length of hydrophobic microblock (NH) in HAPAM is controlled by the molar fraction of DMHAB in mixed micelles, which can be mediated by the ratio of CTAB to DMHAB. The results of steady-state fluorescence probe and viscometry experiments showed the ability of HAPAM association was determined by the length of the hydrophobic microblock. HAPAM with tunable association ability are promising materials for thickening agent.
2009, 20(11): 1366-1370
doi: 10.1016/j.cclet.2009.06.026
Abstract:
In this paper, a thiol-functionalized nanophotocatalyst MPTES/TiO 2 was first synthesized by one-pot method using P123 as a template. X-ray diffraction confirms the complete anatase crystalline of thiol-functionalized TiO 2, N2adsorption-desorption isotherm demonstrated that these materials possess high surface area and mesoporous structure. The results of XPS show that MPTES has been successfully polymerized in mesoporous structured SiO2. The photodegradation of phenanthrene (PHE) was investigated under visible light irradiation (λ > 420 nm) to evaluate the photocatalytic activity of these materials. Based the experiment results of GC-Mass analysis, a possible mechanism was proposed.
In this paper, a thiol-functionalized nanophotocatalyst MPTES/TiO 2 was first synthesized by one-pot method using P123 as a template. X-ray diffraction confirms the complete anatase crystalline of thiol-functionalized TiO 2, N2adsorption-desorption isotherm demonstrated that these materials possess high surface area and mesoporous structure. The results of XPS show that MPTES has been successfully polymerized in mesoporous structured SiO2. The photodegradation of phenanthrene (PHE) was investigated under visible light irradiation (λ > 420 nm) to evaluate the photocatalytic activity of these materials. Based the experiment results of GC-Mass analysis, a possible mechanism was proposed.
2009, 20(11): 1371-1375
doi: 10.1016/j.cclet.2009.07.019
Abstract:
The new macroscopic-scale SBA-15 spheres with diameter of 0.2-0.5 mm are prepared by a sol-gel method, in which the tetrabutylorthosilicate (TBOS) is used as silicon source and triblock copolymer (P123) and polyoxyethylene octylphenol ether (OP10)are used as templates. The resulting spherical samples are characterized by XRD, N 2 adsorption-desorption, TEM and SEM methods. The results show that the inner structure of SBA-15 macrospheres has macroporous channels (0.5 μm) and mesoporous skeleton (4-5 nm). These SBA-15 macrospheres with the hierarchical pore structure demonstrate high absorption capacity for Emodin molecules.
The new macroscopic-scale SBA-15 spheres with diameter of 0.2-0.5 mm are prepared by a sol-gel method, in which the tetrabutylorthosilicate (TBOS) is used as silicon source and triblock copolymer (P123) and polyoxyethylene octylphenol ether (OP10)are used as templates. The resulting spherical samples are characterized by XRD, N 2 adsorption-desorption, TEM and SEM methods. The results show that the inner structure of SBA-15 macrospheres has macroporous channels (0.5 μm) and mesoporous skeleton (4-5 nm). These SBA-15 macrospheres with the hierarchical pore structure demonstrate high absorption capacity for Emodin molecules.
2009, 20(11): 1376-1380
doi: 10.1016/j.cclet.2009.07.021
Abstract:
An efficient strategy that comprised shorten, chain extension, active groups introducing and homogeneous reaction tactics, was adopted to modify multiwalled carbon nanotubes (MWNTs) with cellulose acetate (CA). Specially, by utilizing 2,4,6-trichloro1,3,5-triazine, a reactive intermediate of the MWNTs (MWNT-triazine) was obtained. Suitable sol bility of the MWNT-triazine helps make the homogeneous modification become reality. Detailed characterizations further verified that reaction between chloride atoms in the MWNT-triazine and hydroxyl groups in the CA had contributed to the formation of MWNT-CA conjugates. The novel MWNT-CA consists of carbon (76.3%), oxygen (18.4%) and nitrogen (5.3%). With a nanotube-attached CA content of 42.8 wt%,the MWNT-CA is readily soluble in DMSO, NMP, DMF and DMAc. Confirmation of the CA-based modification route might lead to studies aiming for specific sorption and isolation.
An efficient strategy that comprised shorten, chain extension, active groups introducing and homogeneous reaction tactics, was adopted to modify multiwalled carbon nanotubes (MWNTs) with cellulose acetate (CA). Specially, by utilizing 2,4,6-trichloro1,3,5-triazine, a reactive intermediate of the MWNTs (MWNT-triazine) was obtained. Suitable sol bility of the MWNT-triazine helps make the homogeneous modification become reality. Detailed characterizations further verified that reaction between chloride atoms in the MWNT-triazine and hydroxyl groups in the CA had contributed to the formation of MWNT-CA conjugates. The novel MWNT-CA consists of carbon (76.3%), oxygen (18.4%) and nitrogen (5.3%). With a nanotube-attached CA content of 42.8 wt%,the MWNT-CA is readily soluble in DMSO, NMP, DMF and DMAc. Confirmation of the CA-based modification route might lead to studies aiming for specific sorption and isolation.
2009, 20(11): 1381-1385
doi: 10.1016/j.cclet.2009.05.015
Abstract:
A new 3D extended structural compound, (dpdo)2H2{[Cu(2,2'-bipy)2]2 (P2W18O62)}·5H2O 1 (dpdo=4,4'-bipyridine-N,N'- dioxide; 2,2'-bipy =2,2'-bipyridine), has been hydrothermally synthesized and characterized by elemental analyses, IR, TG analyses, cyclic voltammetry, and single-crystal X-ray diffraction. Compound 1 is built up of [P2W18O62]6- cluster as the structural motif covalently linked by [Cu(2,2'-bipy)2] 2+coordination complexes to yield the 1D chains, which are further in close contact forming a 3D supramolecular framework via aromatic π-π stacking interactions and extensive hydrogen-bonding interactions among polyoxoanions, coordinated 2,2'-bipy organic ligands, free dpdo organic molecules and lattice water molecules.
A new 3D extended structural compound, (dpdo)2H2{[Cu(2,2'-bipy)2]2 (P2W18O62)}·5H2O 1 (dpdo=4,4'-bipyridine-N,N'- dioxide; 2,2'-bipy =2,2'-bipyridine), has been hydrothermally synthesized and characterized by elemental analyses, IR, TG analyses, cyclic voltammetry, and single-crystal X-ray diffraction. Compound 1 is built up of [P2W18O62]6- cluster as the structural motif covalently linked by [Cu(2,2'-bipy)2] 2+coordination complexes to yield the 1D chains, which are further in close contact forming a 3D supramolecular framework via aromatic π-π stacking interactions and extensive hydrogen-bonding interactions among polyoxoanions, coordinated 2,2'-bipy organic ligands, free dpdo organic molecules and lattice water molecules.
2009, 20(11): 1386-1388
doi: 10.1016/j.cclet.2009.04.007
Abstract:
HIV-1 RT is an important target for the treatment of AIDS. There are two major classes of antiviral agents that inhibit HIV-1 RT have been identified, nucleoside RT inhibitors (NRTIs) and non-nucleoside RT inhibitors (NNRTIs). In this report, a noval class of non-nucleoside compound with potential RT inhibitory activity were found from the traditional Chinese medicines database (TCMD) using a combination of virtual screening, docking, molecular dynamic simulations, where results were ranked by scoring function of the docking tool. The result indicates that M4753 (a compound derived from TCMD) has not only the lowest bonding energy but also the best match in geometric conformation with the forthcoming NNRTIs. Accordingly M4753 might possibly become a promising lead compound of NNRTIs for AIDS therapy.
HIV-1 RT is an important target for the treatment of AIDS. There are two major classes of antiviral agents that inhibit HIV-1 RT have been identified, nucleoside RT inhibitors (NRTIs) and non-nucleoside RT inhibitors (NNRTIs). In this report, a noval class of non-nucleoside compound with potential RT inhibitory activity were found from the traditional Chinese medicines database (TCMD) using a combination of virtual screening, docking, molecular dynamic simulations, where results were ranked by scoring function of the docking tool. The result indicates that M4753 (a compound derived from TCMD) has not only the lowest bonding energy but also the best match in geometric conformation with the forthcoming NNRTIs. Accordingly M4753 might possibly become a promising lead compound of NNRTIs for AIDS therapy.
2009, 20(11): 1389-1392
doi: 10.1016/j.cclet.2009.05.029
Abstract:
Cyanide ion was studied as an inhibitor of Jack bean urease at 300 K in 30 mmol/L tris buffer, pH 7. The inhibition was investigated by isothermal titration calorimetry (ITC). The extended solvation model was used for CN -+ JBU interaction over the whole range of CN-concentrations. The binding parameters recovered from the solvation model were attributed to the cyanide ion interaction. It was found that cyanide ion acted as a non-cooperative inhibitor of urease, and there is a set of 12±0.12 identical and independent binding sites for CN- ions. The dissociation equilibrium constant is 749.99 mmol/L. The molar enthalpy of binding is △H=-13.60 kJ mol-1.
Cyanide ion was studied as an inhibitor of Jack bean urease at 300 K in 30 mmol/L tris buffer, pH 7. The inhibition was investigated by isothermal titration calorimetry (ITC). The extended solvation model was used for CN -+ JBU interaction over the whole range of CN-concentrations. The binding parameters recovered from the solvation model were attributed to the cyanide ion interaction. It was found that cyanide ion acted as a non-cooperative inhibitor of urease, and there is a set of 12±0.12 identical and independent binding sites for CN- ions. The dissociation equilibrium constant is 749.99 mmol/L. The molar enthalpy of binding is △H=-13.60 kJ mol-1.
