Login In
2006 Volume 17 Issue 10
2006, 17(10): 1279-1282
Abstract:
An analog of phthalascidin (Pt-650) was synthesized with an improved synthetic route.With precursor 2 as the starting material, compound 1 was prepared through 4 steps in a total yield of 47%. In vitro antitumor test of this Pt-650 analog showed that it possessed strong toxicity against a number of tumor cell lines including A2780, A549, Bel-7402, BGC-823, HELA, KB,KeTr3 and HCT-8.
An analog of phthalascidin (Pt-650) was synthesized with an improved synthetic route.With precursor 2 as the starting material, compound 1 was prepared through 4 steps in a total yield of 47%. In vitro antitumor test of this Pt-650 analog showed that it possessed strong toxicity against a number of tumor cell lines including A2780, A549, Bel-7402, BGC-823, HELA, KB,KeTr3 and HCT-8.
2006, 17(10): 1283-1286
Abstract:
An operationally simple and inexpensive catalyst system was developed for the cross coupling of potassium thiocyanate with aryl iodides by using CuI as catalyst, 1, 10-phenanthroline as ligand, and tetraethylammonium iodide as activator. The procedure is applicable for the synthesis of diverse aryl thiocyanates without any exotic, poisonous reagents.
An operationally simple and inexpensive catalyst system was developed for the cross coupling of potassium thiocyanate with aryl iodides by using CuI as catalyst, 1, 10-phenanthroline as ligand, and tetraethylammonium iodide as activator. The procedure is applicable for the synthesis of diverse aryl thiocyanates without any exotic, poisonous reagents.
2006, 17(10): 1287-1288
Abstract:
First total synthesis of saurufuran B 1, a furanoditerpene, from (E, E)-farnesol 2 and citraconic anhydride 3 through thirteen steps is described. Our work involves two key steps:(1)High regioselective alkylation of 2-(tert-butyldimethylsiloxy)-4-methylfuran 6 with allylic iodides 5 in the presence of silver trifluoroacetate1 and (2) Conversion of substituted γ-lactone 7 into furan derivative 82.
First total synthesis of saurufuran B 1, a furanoditerpene, from (E, E)-farnesol 2 and citraconic anhydride 3 through thirteen steps is described. Our work involves two key steps:(1)High regioselective alkylation of 2-(tert-butyldimethylsiloxy)-4-methylfuran 6 with allylic iodides 5 in the presence of silver trifluoroacetate1 and (2) Conversion of substituted γ-lactone 7 into furan derivative 82.
2006, 17(10): 1289-1292
Abstract:
The first total synthesis of natural 6β-cinnamoyloxy-1α-hydroxy-5, 10-bis-epi-eudesm-4-en-3-one (1), a highly complex natural eudesmane, was described.
The first total synthesis of natural 6β-cinnamoyloxy-1α-hydroxy-5, 10-bis-epi-eudesm-4-en-3-one (1), a highly complex natural eudesmane, was described.
2006, 17(10): 1293-1296
Abstract:
An efficient, environmentally friendly procedure is developed for the condensation of aldehydes/ketones and activatedmethylene compounds by using an aminopropyl-functionalized MCM-41 catalyst in aqueoussolution. Different aldehydes/ketones and activated methylene compounds gave thecorresponding alkenes in 78-97% isolated yields in mild reaction conditions.In comparison with organic solution, the aqueous solution gives higher yields in the same reaction conditions. Furthermore, the aminopropyl-functionalized MCM-41 in aqueous system can be reused for 8 times without significant decrease of activity.
An efficient, environmentally friendly procedure is developed for the condensation of aldehydes/ketones and activatedmethylene compounds by using an aminopropyl-functionalized MCM-41 catalyst in aqueoussolution. Different aldehydes/ketones and activated methylene compounds gave thecorresponding alkenes in 78-97% isolated yields in mild reaction conditions.In comparison with organic solution, the aqueous solution gives higher yields in the same reaction conditions. Furthermore, the aminopropyl-functionalized MCM-41 in aqueous system can be reused for 8 times without significant decrease of activity.
2006, 17(10): 1297-1300
Abstract:
An array of C2-symmetric chiral Schiff bases of substituted salicylaldehyde (1R, 2R)-1,2-cyclohexanediamine and (R)-(+)-2, 2'-diamino-1, 1'-binaphthalene, incorporated with lanthanide complexes, have been applied as catalysts for asymmetric hydrogenation of acetophenone for the first time. Highly enantioselective product with 90% enantiomeric excess (e.e.) was obtained when the catalyst, hybridized by the bulky electron-donating 3, 5-di-tert-butyl substituted Schiff base (2) and SmCl3·4THF, was employed.
An array of C2-symmetric chiral Schiff bases of substituted salicylaldehyde (1R, 2R)-1,2-cyclohexanediamine and (R)-(+)-2, 2'-diamino-1, 1'-binaphthalene, incorporated with lanthanide complexes, have been applied as catalysts for asymmetric hydrogenation of acetophenone for the first time. Highly enantioselective product with 90% enantiomeric excess (e.e.) was obtained when the catalyst, hybridized by the bulky electron-donating 3, 5-di-tert-butyl substituted Schiff base (2) and SmCl3·4THF, was employed.
2006, 17(10): 1301-1304
Abstract:
A series of novel antitumor agents-the solanesylpiperazinotriamine derivatives were designed and synthesized, their structures were confirmed by IR, 1H-NMR, MS, and element analysis. The preliminary tests showed that at low micromolar concentrations these compounds exhibited obvious toxicity on tumor cells in vitro, and the synergistic effect on clinical antitumor agent indicated that at noncytotoxic concentrations they also evidently enhanced the curative effect of vincristine.
A series of novel antitumor agents-the solanesylpiperazinotriamine derivatives were designed and synthesized, their structures were confirmed by IR, 1H-NMR, MS, and element analysis. The preliminary tests showed that at low micromolar concentrations these compounds exhibited obvious toxicity on tumor cells in vitro, and the synergistic effect on clinical antitumor agent indicated that at noncytotoxic concentrations they also evidently enhanced the curative effect of vincristine.
2006, 17(10): 1305-1308
Abstract:
A novel benzoxazine monomer containing aldehyde group, 3-phenyl-6-formyl-3,4-dihydro-2H-1, 3-benzoxazine (Ald-B), was synthesized via the Mannich condensation of formaldehyde, p-hydroxybenzaldehyde and aniline. Its structure was characterized by Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1HNMR). The side reaction in the synthesis is discussed.
A novel benzoxazine monomer containing aldehyde group, 3-phenyl-6-formyl-3,4-dihydro-2H-1, 3-benzoxazine (Ald-B), was synthesized via the Mannich condensation of formaldehyde, p-hydroxybenzaldehyde and aniline. Its structure was characterized by Fourier transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1HNMR). The side reaction in the synthesis is discussed.
2006, 17(10): 1309-1312
Abstract:
A convenient, efficient, one-pot, novel process has been developed for the synthesis of carbamates from corresponding alkyl halides and amines using basic resin/CO2 system.
A convenient, efficient, one-pot, novel process has been developed for the synthesis of carbamates from corresponding alkyl halides and amines using basic resin/CO2 system.
2006, 17(10): 1313-1316
Abstract:
Several of new chelating resins containing sulfoxide and heterocyclic functional groups (3-aminopyridine and 2-mercaptobenzothiazole) based on macroporous chloromethylated polystyrene were synthesized and characterized by elemental analysis and infrared spectra. Their adsorption capacities towards Zn2+, Cu2+, Pb2+, Hg2+ and Ag+ at pH 3.0 and 6.0 were investigated in detail. It was found that the adsorption capacities of the resins containing bis[(3-pyridylaminoethyl)sulfoxide or (2-benzothiazolylthioethyl) sulfoxide for the above ions were higher than that on ones containing single above-mentioned groups.
Several of new chelating resins containing sulfoxide and heterocyclic functional groups (3-aminopyridine and 2-mercaptobenzothiazole) based on macroporous chloromethylated polystyrene were synthesized and characterized by elemental analysis and infrared spectra. Their adsorption capacities towards Zn2+, Cu2+, Pb2+, Hg2+ and Ag+ at pH 3.0 and 6.0 were investigated in detail. It was found that the adsorption capacities of the resins containing bis[(3-pyridylaminoethyl)sulfoxide or (2-benzothiazolylthioethyl) sulfoxide for the above ions were higher than that on ones containing single above-mentioned groups.
2006, 17(10): 1317-1320
Abstract:
A series of novel ligustrazine derivatives were synthesized. These compounds have not been reported in literature, and their chemical structures were confirmed by IR, 1H NMR and ESI-MS. The preliminary antiplatelet aggregation screening results demonstrated that the compounds 7a, 7b and 7c showed higher potency than ligustrazine.
A series of novel ligustrazine derivatives were synthesized. These compounds have not been reported in literature, and their chemical structures were confirmed by IR, 1H NMR and ESI-MS. The preliminary antiplatelet aggregation screening results demonstrated that the compounds 7a, 7b and 7c showed higher potency than ligustrazine.
2006, 17(10): 1321-1324
Abstract:
Two new labdane diterpenoids named heteronone A (1) and heteronone B (2) were isolated from the aerial parts of Leonurus heterophyllus Sweet. Their structures were established by various spectroscopic means, and the structure of heteronone A is confirmed by X-ray diffraction analysis.
Two new labdane diterpenoids named heteronone A (1) and heteronone B (2) were isolated from the aerial parts of Leonurus heterophyllus Sweet. Their structures were established by various spectroscopic means, and the structure of heteronone A is confirmed by X-ray diffraction analysis.
2006, 17(10): 1325-1327
Abstract:
Two new compounds, linderafurane A and linchuniinone, were isolated from the root of Lindera chunii Merr.. The structures were elucidated by spectroscopic methods,and their activities against HIV-1 integrase were evaluated.
Two new compounds, linderafurane A and linchuniinone, were isolated from the root of Lindera chunii Merr.. The structures were elucidated by spectroscopic methods,and their activities against HIV-1 integrase were evaluated.
2006, 17(10): 1328-1330
Abstract:
A novel flavone glycoside named 3"'-carbonyl-2"-β-L-quinovosyl icariside Ⅱ was isolated from the aerial parts of Epimedium koreanum. Its chemical structure was elucidated on the basis of spectral analysis.
A novel flavone glycoside named 3"'-carbonyl-2"-β-L-quinovosyl icariside Ⅱ was isolated from the aerial parts of Epimedium koreanum. Its chemical structure was elucidated on the basis of spectral analysis.
2006, 17(10): 1331-1334
Abstract:
A new bis-iridoid glucoside, incaside 1 was isolated along with known iridoid, 6-O-veratroylcatalposide from the stem-bark of Mussaenda incana. The structure of the new iridoid was established mainly on the basis of the spectroscopic (including 2D NMR) and chemical studies of its octaacetate 1a.
A new bis-iridoid glucoside, incaside 1 was isolated along with known iridoid, 6-O-veratroylcatalposide from the stem-bark of Mussaenda incana. The structure of the new iridoid was established mainly on the basis of the spectroscopic (including 2D NMR) and chemical studies of its octaacetate 1a.
2006, 17(10): 1335-1338
Abstract:
A furostanol saponin was obtained from the n-butanol fraction of methanol extract from Tupistra chinensis rhizomes, a folk medicine of Shennongjia Forest District of Hubei Province.Its structure was determined as 3-O-β-D-glucopyranosyl-(25S)-22-O-methyl-5β-furost-1β, 3β, 5β,22α, 26-pentaol-26-O-β-D-glucopyranoside (1) on the basis of chemical and spectroscopic evidences. The n-butanol fraction displayed marked inhibitory activity in vitro towards HeLa and HL-60 human tumor cell lines by MTT method.
A furostanol saponin was obtained from the n-butanol fraction of methanol extract from Tupistra chinensis rhizomes, a folk medicine of Shennongjia Forest District of Hubei Province.Its structure was determined as 3-O-β-D-glucopyranosyl-(25S)-22-O-methyl-5β-furost-1β, 3β, 5β,22α, 26-pentaol-26-O-β-D-glucopyranoside (1) on the basis of chemical and spectroscopic evidences. The n-butanol fraction displayed marked inhibitory activity in vitro towards HeLa and HL-60 human tumor cell lines by MTT method.
2006, 17(10): 1339-1342
Abstract:
Two new flavonol glycosides, tamarixetin 3-O-β-D-xylopyranosyl-(1-2)-α-L-ribopyranoside (1) and tamarixetin 3-O-α-L-ribopyranoside (2) were isolated from the leaves of Bridelia tomentosa. Their structures were elucidated by 1D and 2D NMR analysis, as well as MS and IR spectra.
Two new flavonol glycosides, tamarixetin 3-O-β-D-xylopyranosyl-(1-2)-α-L-ribopyranoside (1) and tamarixetin 3-O-α-L-ribopyranoside (2) were isolated from the leaves of Bridelia tomentosa. Their structures were elucidated by 1D and 2D NMR analysis, as well as MS and IR spectra.
2006, 17(10): 1343-1346
Abstract:
A highly sensitive double artificial neural network (DANN) analysis with flow-injection chemiluminescence (FI-CL) has been developed to simultaneously determine the trace amounts of the gold and platinum in simulated mixed samples, without the boring process.
A highly sensitive double artificial neural network (DANN) analysis with flow-injection chemiluminescence (FI-CL) has been developed to simultaneously determine the trace amounts of the gold and platinum in simulated mixed samples, without the boring process.
2006, 17(10): 1347-1350
Abstract:
This work reports the spectrophotometric simultaneous determination of zinc(Ⅱ),manganese(Ⅱ) and iron(Ⅱ) in pharmaceutical preparation, using orthogonal signal correctionpartial least squares (OSC-PLS). All the factors affecting on the sensitivity were optimized and the linear dynamic range for determination of these metals was found. The PLS modeling was used for the multivariate calibration of the spectrophotometric data. The OSC was used for preprocessing of data matrices and the prediction results of model. The experimental calibration matrix was designed by measuring the absorbance over the range 450-570 nm for 21 samples of 0.05-1.05, 0.10-1.10 and 0.05-1.05 μg·mL-1 of zinc(Ⅱ), manganese(Ⅱ) and iron(Ⅱ), respectively. The RMSEP for zinc(Ⅱ), manganese(Ⅱ) and iron(Ⅱ) using OSC-PLS were 0.0164, 0.0132, 0.0146,respectively. The proposed method was successfully applied the determination of zinc(Ⅱ),manganese(Ⅱ) and iron(Ⅱ) in pharmaceutical preparations.
This work reports the spectrophotometric simultaneous determination of zinc(Ⅱ),manganese(Ⅱ) and iron(Ⅱ) in pharmaceutical preparation, using orthogonal signal correctionpartial least squares (OSC-PLS). All the factors affecting on the sensitivity were optimized and the linear dynamic range for determination of these metals was found. The PLS modeling was used for the multivariate calibration of the spectrophotometric data. The OSC was used for preprocessing of data matrices and the prediction results of model. The experimental calibration matrix was designed by measuring the absorbance over the range 450-570 nm for 21 samples of 0.05-1.05, 0.10-1.10 and 0.05-1.05 μg·mL-1 of zinc(Ⅱ), manganese(Ⅱ) and iron(Ⅱ), respectively. The RMSEP for zinc(Ⅱ), manganese(Ⅱ) and iron(Ⅱ) using OSC-PLS were 0.0164, 0.0132, 0.0146,respectively. The proposed method was successfully applied the determination of zinc(Ⅱ),manganese(Ⅱ) and iron(Ⅱ) in pharmaceutical preparations.
2006, 17(10): 1351-1352
Abstract:
Binding of cordycepin to the double helical DNA with a high affinity was investigated by CD spectra in this paper. The results proved that uncoiling, unbinding and denaturation of DNA proceeded continuously upon the increase of the concentration of cordycepin.
Binding of cordycepin to the double helical DNA with a high affinity was investigated by CD spectra in this paper. The results proved that uncoiling, unbinding and denaturation of DNA proceeded continuously upon the increase of the concentration of cordycepin.
2006, 17(10): 1353-1356
Abstract:
It is normally difficult to prepare nano-sized Ba0.5Sr0.5Co0.8Fe0.2O3-δ(BSCF) oxide at high temperature due to its high surface activity. The complexing process, which has successfully applied in the synthesis of nano Sm0.15Ce0.85O1.925 with crystallite size down to 5 nm1, just resulted in a coarse BSCF with crystallite size of 41.9 nm at 900℃. We applied a novel process by simply modifying the solid precursor from the complexing process with concentrated nitric acid treatment.The obtained BSCF powder had a crystallite size of ~25 nm even calcined at 1000℃. The small crystallite size is extremely promising to enhance the electrochemical performance of cathode for solid oxide fuel cell dramatically.
It is normally difficult to prepare nano-sized Ba0.5Sr0.5Co0.8Fe0.2O3-δ(BSCF) oxide at high temperature due to its high surface activity. The complexing process, which has successfully applied in the synthesis of nano Sm0.15Ce0.85O1.925 with crystallite size down to 5 nm1, just resulted in a coarse BSCF with crystallite size of 41.9 nm at 900℃. We applied a novel process by simply modifying the solid precursor from the complexing process with concentrated nitric acid treatment.The obtained BSCF powder had a crystallite size of ~25 nm even calcined at 1000℃. The small crystallite size is extremely promising to enhance the electrochemical performance of cathode for solid oxide fuel cell dramatically.
2006, 17(10): 1357-1360
Abstract:
Mn/Ba/Al2O3 catalyst for NO oxidation-storage and Pt/Ba/Al2O3 catalyst mixed with Mn/Ba/Al2O3 for NOx storage-reduction by hydrogen were investigated. The results showed that Mn/Ba/Al2O3 had large nitrogen oxides storage capacity (397.9 μmolg-1) under lean bum condition.When Pt/Ba/Al2O3 catalyst was mixed with Mn/Ba/Al2O3 in equal weight proportion, the NOx conversion increased between 250℃ and 500℃ under the dynamic lean-rich bum conditions, and the maximum NOx conversion increased from 95.4% to 98.2%. Mn/Ba/Al2O3 has promoted NOx storing in the lean stage and improved NOxreduction efficiency in the rich stage, these might result in higher NOx conversion over the low Pt loading content catalyst.
Mn/Ba/Al2O3 catalyst for NO oxidation-storage and Pt/Ba/Al2O3 catalyst mixed with Mn/Ba/Al2O3 for NOx storage-reduction by hydrogen were investigated. The results showed that Mn/Ba/Al2O3 had large nitrogen oxides storage capacity (397.9 μmolg-1) under lean bum condition.When Pt/Ba/Al2O3 catalyst was mixed with Mn/Ba/Al2O3 in equal weight proportion, the NOx conversion increased between 250℃ and 500℃ under the dynamic lean-rich bum conditions, and the maximum NOx conversion increased from 95.4% to 98.2%. Mn/Ba/Al2O3 has promoted NOx storing in the lean stage and improved NOxreduction efficiency in the rich stage, these might result in higher NOx conversion over the low Pt loading content catalyst.
2006, 17(10): 1361-1364
Abstract:
A novel, reactive amide-bridged ladder polyvinylsiloxane (abbr. LP) with Mn=2.4×104 was synthesized for the first time by means of aryl amide H-bonding self-assembled template.The regularity of LP was characterized by the XRD, 29Si NMR and DSC methods. XRD analysis demonstrated the ladder width w=9.09Å and the ladder thickness t=3.89Å, respectively, which are approximately consistent with the molecular simulation-calculated ones:w'=10.60Å and t'=3.06Å. 29Si NMR displayed a resonance peak with small half peak width, △1/2~4 ppm, for the moiety[=Si(Vi)O2/2-]n of LP. Besides, as a collateral evidence, DSC measurement revealed a high glass transition temperature Tg=225℃, suggesting high stiffness of the ladder main chain of LP.
A novel, reactive amide-bridged ladder polyvinylsiloxane (abbr. LP) with Mn=2.4×104 was synthesized for the first time by means of aryl amide H-bonding self-assembled template.The regularity of LP was characterized by the XRD, 29Si NMR and DSC methods. XRD analysis demonstrated the ladder width w=9.09Å and the ladder thickness t=3.89Å, respectively, which are approximately consistent with the molecular simulation-calculated ones:w'=10.60Å and t'=3.06Å. 29Si NMR displayed a resonance peak with small half peak width, △1/2~4 ppm, for the moiety[=Si(Vi)O2/2-]n of LP. Besides, as a collateral evidence, DSC measurement revealed a high glass transition temperature Tg=225℃, suggesting high stiffness of the ladder main chain of LP.
2006, 17(10): 1365-1368
Abstract:
Novel biodegradable copolymer poly(CC-co-EEP) was synthesized by ring-opening copolymerization of cyclic carbonate 9-phenyl-2, 4, 8, 10-tetraoxaspiro-[5, 5]undcane-3-one (CC)and ethylene ethyl phosphate (EEP). The obtained poly (CC-co-EEP)s were characterized by FTIR, 1H NMR, 13C NMR and gel permeation chromatography (GPC). In vitro hydrolytic degradation of the copolymers were investigated in phosphate buffer solution (pH=7.4).Hydrophilic phosphate units apparently improved the degradability of poly(carbonate-phosphate).
Novel biodegradable copolymer poly(CC-co-EEP) was synthesized by ring-opening copolymerization of cyclic carbonate 9-phenyl-2, 4, 8, 10-tetraoxaspiro-[5, 5]undcane-3-one (CC)and ethylene ethyl phosphate (EEP). The obtained poly (CC-co-EEP)s were characterized by FTIR, 1H NMR, 13C NMR and gel permeation chromatography (GPC). In vitro hydrolytic degradation of the copolymers were investigated in phosphate buffer solution (pH=7.4).Hydrophilic phosphate units apparently improved the degradability of poly(carbonate-phosphate).
2006, 17(10): 1369-1372
Abstract:
A new polysaccharide was extracted and purified from the roots of Angelica sinensis (Oliv) Diels (ASD). Its composition and linkage was elucidated by selective hydrolysis and GC/MS analysis of its derivatives. The polysaccharide was made of→1) Fruf(2→and→6) GlCp (1→as its backbone with highly branched structure. To our best knowledge, this is the first report of the fructose residue in polysaccharides from the roots of the ASD.
A new polysaccharide was extracted and purified from the roots of Angelica sinensis (Oliv) Diels (ASD). Its composition and linkage was elucidated by selective hydrolysis and GC/MS analysis of its derivatives. The polysaccharide was made of→1) Fruf(2→and→6) GlCp (1→as its backbone with highly branched structure. To our best knowledge, this is the first report of the fructose residue in polysaccharides from the roots of the ASD.
2006, 17(10): 1373-1376
Abstract:
Poly(phenylene sulfide/ether) (PPSE) was synthesized from 4,4'-dihydroxydiphenyl sulfide and 4,4'-dichlorodiphenyl sulfide in solution by nucleophilic substitution reaction. The resulting polymer was characterized by viscosity measurement, elemental analysis, FT-IR,1H NMR, X-ray diffraction and thermal analysis. The results showed that the viscosities of the resulting polymer were above 0.68 dL/g, and the linear chain structure of product was confirmed.PPSE had the same reflex indices as poly(p-phenylene sulfide), an orthorhombic crystalline with unit cell a=0.853, b=0.562, c=1.026nm. The melting temperature, glass transition temperature and initial decomposition temperature were found to be 228℃, 85℃ and 325℃, respectively.The product was soluble in common organic solvents such as NMP, N, N'-dimethylformamide,N, N'-dimethylacetamide and 1,2-dichloroethane.
Poly(phenylene sulfide/ether) (PPSE) was synthesized from 4,4'-dihydroxydiphenyl sulfide and 4,4'-dichlorodiphenyl sulfide in solution by nucleophilic substitution reaction. The resulting polymer was characterized by viscosity measurement, elemental analysis, FT-IR,1H NMR, X-ray diffraction and thermal analysis. The results showed that the viscosities of the resulting polymer were above 0.68 dL/g, and the linear chain structure of product was confirmed.PPSE had the same reflex indices as poly(p-phenylene sulfide), an orthorhombic crystalline with unit cell a=0.853, b=0.562, c=1.026nm. The melting temperature, glass transition temperature and initial decomposition temperature were found to be 228℃, 85℃ and 325℃, respectively.The product was soluble in common organic solvents such as NMP, N, N'-dimethylformamide,N, N'-dimethylacetamide and 1,2-dichloroethane.
2006, 17(10): 1377-1380
Abstract:
Novel interpenetrating polymer network (IPN) hydrogels based on konjac glucomannan (KGM) and poly(acrylic acid) (PAA) were prepared by polymerization and cross-linking of acrylic acid (AA) in the pre-fabricated KGM gel. The IPN gel was analyzed by FT-IR. The studies on the equilibrium swelling ratio of IPN hydrogels revealed their sensitive response to environmental pH value. The results of in vitro degradation showed that the IPN hydrogels retain the enzymatic degradation character of KGM.
Novel interpenetrating polymer network (IPN) hydrogels based on konjac glucomannan (KGM) and poly(acrylic acid) (PAA) were prepared by polymerization and cross-linking of acrylic acid (AA) in the pre-fabricated KGM gel. The IPN gel was analyzed by FT-IR. The studies on the equilibrium swelling ratio of IPN hydrogels revealed their sensitive response to environmental pH value. The results of in vitro degradation showed that the IPN hydrogels retain the enzymatic degradation character of KGM.
2006, 17(10): 1381-1384
Abstract:
Novel π-conjugated polymers constituted of 2,1,3-benzothiadiazole or cyano-containing unit copolymers were synthesized and characterized by UV-Vis, IR and PL.
Novel π-conjugated polymers constituted of 2,1,3-benzothiadiazole or cyano-containing unit copolymers were synthesized and characterized by UV-Vis, IR and PL.
2006, 17(10): 1385-1387
Abstract:
Novel polycarbonates from 5-allyloxy-1, 3-dioxan-2-one (ATMC) with 5, 5-dimethyl1, 3-dioxan-2-one (DTC) were successfully synthesized for the first time using immobilized porcine pancreas lipase (IPPL) as catalyst. The resulting copolymers were characterized by IR,1HNMR, 13C NMR and GPC. The molecular weight (Mn) of the copolymer with molar feed ratio of 10:90(ATMC:DTC) was 9300 and the polydispersity was 1.31, while the Mn increased to 14300 and polydispersity of 1.25 with the feed ratio of 50:50. Moreover, the composition of the copolymers agreed well with the monomer feed.
Novel polycarbonates from 5-allyloxy-1, 3-dioxan-2-one (ATMC) with 5, 5-dimethyl1, 3-dioxan-2-one (DTC) were successfully synthesized for the first time using immobilized porcine pancreas lipase (IPPL) as catalyst. The resulting copolymers were characterized by IR,1HNMR, 13C NMR and GPC. The molecular weight (Mn) of the copolymer with molar feed ratio of 10:90(ATMC:DTC) was 9300 and the polydispersity was 1.31, while the Mn increased to 14300 and polydispersity of 1.25 with the feed ratio of 50:50. Moreover, the composition of the copolymers agreed well with the monomer feed.
2006, 17(10): 1388-1390
Abstract:
New hydrogen bonded supramolecular hydrogels were formed through simultaneously gelating two isomeric building units, 4-oxo-4-(2-pyridinylamino)butanoic acid (G1) and 4-oxo-4-(3-pyridinylamino)butanoic acid (G2) at various molar ratios in water.
New hydrogen bonded supramolecular hydrogels were formed through simultaneously gelating two isomeric building units, 4-oxo-4-(2-pyridinylamino)butanoic acid (G1) and 4-oxo-4-(3-pyridinylamino)butanoic acid (G2) at various molar ratios in water.
2006, 17(10): 1391-1393
Abstract:
The preparation of sterically stabilized poly(3, 4-ethylenedioxythiophene)(PEDOT)colloidal dispersions doped with different sulfonic acids is described. Three different sulfonic acids, i.e., p-toluenesulfonic acid, β-naphthalenesuffonic acid and D-camphor-10-sulfonic acid are used, facilitating the preparation of sterically stable PEDOT colloidal particles. The influences of the dopants and concentration of polymeric stabilizer on the yields, morphologies and electrical properties of the resultant colloidal particles were investigated. The colloidal particles with the size ranging from 172 to 334 nm have been obtained in good yields. The compressed pellet conductivity was as high as 4.5 Scm-1.
The preparation of sterically stabilized poly(3, 4-ethylenedioxythiophene)(PEDOT)colloidal dispersions doped with different sulfonic acids is described. Three different sulfonic acids, i.e., p-toluenesulfonic acid, β-naphthalenesuffonic acid and D-camphor-10-sulfonic acid are used, facilitating the preparation of sterically stable PEDOT colloidal particles. The influences of the dopants and concentration of polymeric stabilizer on the yields, morphologies and electrical properties of the resultant colloidal particles were investigated. The colloidal particles with the size ranging from 172 to 334 nm have been obtained in good yields. The compressed pellet conductivity was as high as 4.5 Scm-1.
2006, 17(10): 1394-1396
Abstract:
Inspired by the locomotion of terrestrial limbless animals, the present work attempt to study the motion of biomimetic system based on poly(vinyl alcohol)/dimethylsulfoxide gel. The system was operated in air by employing a non-contacted DC electric field. The results showed that the gel exhibited a long-range snail-like motion and had a very fast response rate.
Inspired by the locomotion of terrestrial limbless animals, the present work attempt to study the motion of biomimetic system based on poly(vinyl alcohol)/dimethylsulfoxide gel. The system was operated in air by employing a non-contacted DC electric field. The results showed that the gel exhibited a long-range snail-like motion and had a very fast response rate.
2006, 17(10): 1397-1400
Abstract:
A sinter-locked three-dimensional network of microfibrous nickel catalyst has been fabricated based on wet layup papermaking and sintering processes and this novel approach permits the production of ~11 W fuel cell power H2 via NH3 decomposition with a conversion of 97% at 750℃ in a bed of 0.6 cm3.
A sinter-locked three-dimensional network of microfibrous nickel catalyst has been fabricated based on wet layup papermaking and sintering processes and this novel approach permits the production of ~11 W fuel cell power H2 via NH3 decomposition with a conversion of 97% at 750℃ in a bed of 0.6 cm3.
2006, 17(10): 1401-1404
Abstract:
New super-hydrophobic nanocomposite coatings were formed from modified nano-sized CaCO3 particles and polyacrylate at weight ratio of 9/1-8/2. SEM and XPS analysis indicated that such hydrophobicity could be attributed to the surface nano-microstructure and the surface enrichment of fluorine atoms. As the surface hydrophobicity increased, longer time was required for formation the initial frost, which makes super-hydrophobic coatings suitable for anti-frosting purpose.
New super-hydrophobic nanocomposite coatings were formed from modified nano-sized CaCO3 particles and polyacrylate at weight ratio of 9/1-8/2. SEM and XPS analysis indicated that such hydrophobicity could be attributed to the surface nano-microstructure and the surface enrichment of fluorine atoms. As the surface hydrophobicity increased, longer time was required for formation the initial frost, which makes super-hydrophobic coatings suitable for anti-frosting purpose.
2006, 17(10): 1405-1408
Abstract:
Single-crystalline, regular-edged gold nanoplates are synthesized through chemical reduction of AuCl4- by a suitable amount of citrate at room temperature, without additional capping agents or surfactants. The suitable molar ratio of sodium citrate to HAuCl4, low reaction temperature and the presence of natural light are critical factors for the formation of the regularly shaped nanoplates.
Single-crystalline, regular-edged gold nanoplates are synthesized through chemical reduction of AuCl4- by a suitable amount of citrate at room temperature, without additional capping agents or surfactants. The suitable molar ratio of sodium citrate to HAuCl4, low reaction temperature and the presence of natural light are critical factors for the formation of the regularly shaped nanoplates.
2006, 17(10): 1409-1412
Abstract:
A TAPO-11 molecular sieve with the space group Icm2 was synthesized successfully.The samples with different space group were controlled simply only by adjusting the crystallization temperature (CT) in the hydrothermal system. In the system of gel with a molar composition of 0.7R:xTiO2:P2O5:Al2O3:30H2O, where x is 0.01-0.10 and the R is a mixture of di-n-propylamine and diisopropylamine as templates. When CT was between 150-160℃, the calcined sample showed the space group of Icm2, while it showed Pna21 at CTlarger than 190℃.The characterizations of UV-Vis and FT-IR confirmed that Ti was incorporated into the AEL framework successfully.
A TAPO-11 molecular sieve with the space group Icm2 was synthesized successfully.The samples with different space group were controlled simply only by adjusting the crystallization temperature (CT) in the hydrothermal system. In the system of gel with a molar composition of 0.7R:xTiO2:P2O5:Al2O3:30H2O, where x is 0.01-0.10 and the R is a mixture of di-n-propylamine and diisopropylamine as templates. When CT was between 150-160℃, the calcined sample showed the space group of Icm2, while it showed Pna21 at CTlarger than 190℃.The characterizations of UV-Vis and FT-IR confirmed that Ti was incorporated into the AEL framework successfully.
2006, 17(10): 1413-1416
Abstract:
Colloidal dispersion of nano-Ru/SiO2 in PEG (polyethylene glycol, M.W.=400) was used for benzene hydrogenation. The system has the features of easy catalyst's recycling and high catalyst stability.
Colloidal dispersion of nano-Ru/SiO2 in PEG (polyethylene glycol, M.W.=400) was used for benzene hydrogenation. The system has the features of easy catalyst's recycling and high catalyst stability.
2006, 17(10): 1417-1420
Abstract:
As far as we known, with white powdery tungstic acid (WPTA) used as the dopant for the first time, tungsten-doped vanadium dioxide (VO2) nanopowders were synthesized through thermolysis at low temperature. The products were characterized by XRD, TEM and DSC.When WPTA was added into V2O5 (with W/V=2 atom%), the phase transition temperature (Tc)of VO2 decreased markedly from 67.15℃ to 26.46℃ after annealing at 500℃. Such a low Tc is beneficial to the application and development of smart windows materials.
As far as we known, with white powdery tungstic acid (WPTA) used as the dopant for the first time, tungsten-doped vanadium dioxide (VO2) nanopowders were synthesized through thermolysis at low temperature. The products were characterized by XRD, TEM and DSC.When WPTA was added into V2O5 (with W/V=2 atom%), the phase transition temperature (Tc)of VO2 decreased markedly from 67.15℃ to 26.46℃ after annealing at 500℃. Such a low Tc is beneficial to the application and development of smart windows materials.
