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2003 Volume 14 Issue 5
2003, 14(5): 441-442
Abstract:
The first total synthesis of (±)-abieta-8, 11, 13-trien-7β-ol (7) was accomplished via a strategy of AC→ABC, in which the reduction of the ketone 6 with LiAlH4 gave exclusively the title compound.
The first total synthesis of (±)-abieta-8, 11, 13-trien-7β-ol (7) was accomplished via a strategy of AC→ABC, in which the reduction of the ketone 6 with LiAlH4 gave exclusively the title compound.
2003, 14(5): 443-444
Abstract:
The first total synthesis of (±)-3',7-dihydroxy-4'-methoxyflavan,a naturally occurring flavan, was described. The key step is the cyclization of 1,3-diaryl-1-propanol by BF3·Et2O.
The first total synthesis of (±)-3',7-dihydroxy-4'-methoxyflavan,a naturally occurring flavan, was described. The key step is the cyclization of 1,3-diaryl-1-propanol by BF3·Et2O.
2003, 14(5): 445-447
Abstract:
A novel β-cyclodextrin-based terpyridine derivatives has been prepared by the coupling of 4'-(4"-bromomethyl phenyl)-2, 2':6', 2"-terpyridine with mono-6-hydroxy permethylated β-cyclodextrin.The cyclodextrin dimmer appending a 4'-phenyl-2,2':6',2"-terpyridine spacer on the primary faces was synthesized by reaction of 4'-phenyl-2,2':6',2'-terpyridine-6,6'-dicarbonitrile with an excess of 6-deoxy-6-O-tosyl-β-cyclodextrin.
A novel β-cyclodextrin-based terpyridine derivatives has been prepared by the coupling of 4'-(4"-bromomethyl phenyl)-2, 2':6', 2"-terpyridine with mono-6-hydroxy permethylated β-cyclodextrin.The cyclodextrin dimmer appending a 4'-phenyl-2,2':6',2"-terpyridine spacer on the primary faces was synthesized by reaction of 4'-phenyl-2,2':6',2'-terpyridine-6,6'-dicarbonitrile with an excess of 6-deoxy-6-O-tosyl-β-cyclodextrin.
2003, 14(5): 448-450
Abstract:
The Knoevenagel condensation of carbonyl substrates with active methylene compounds proceeds smoothly with ammonium acetate as catalyst in n-butyl pyridinium nitrate to afford the desired products of good purity in moderate yields.
The Knoevenagel condensation of carbonyl substrates with active methylene compounds proceeds smoothly with ammonium acetate as catalyst in n-butyl pyridinium nitrate to afford the desired products of good purity in moderate yields.
2003, 14(5): 451-452
Abstract:
Poly[styrene(iodosodiacetate)] reacted with diaryl diselenides, followed by sodium azide, giving 1-azido-2-arylselenoalkanes regioselectively.The polymer reagent could be regenerated and reused.
Poly[styrene(iodosodiacetate)] reacted with diaryl diselenides, followed by sodium azide, giving 1-azido-2-arylselenoalkanes regioselectively.The polymer reagent could be regenerated and reused.
2003, 14(5): 453-455
Abstract:
Reacting calix[6]arene hexaesters with poly(ethyleneimine), a series of calix [6]amides-based polymers were obtained for the first time.It is found that they show high absorption capacities towards soft cations comparing to hard cations, and the absorption abilities enhanced with the increasing of calixarene content, which may indicates the cavity of calixarene plays crucial role in absorption.Polymer 2c shows good selective absorption capability towards Ag+ among the tested cations.
Reacting calix[6]arene hexaesters with poly(ethyleneimine), a series of calix [6]amides-based polymers were obtained for the first time.It is found that they show high absorption capacities towards soft cations comparing to hard cations, and the absorption abilities enhanced with the increasing of calixarene content, which may indicates the cavity of calixarene plays crucial role in absorption.Polymer 2c shows good selective absorption capability towards Ag+ among the tested cations.
2003, 14(5): 456-458
Abstract:
Polystyrene-supported 4-(phenylseleno)morpholine was synthesized and could be used as an efficient α-selenenylating agent for saturated aldehydes.α-Haloaldehydes were prepared by reaction of polystyrene-supported α-selenoaldehydes with bromine or sulfuryl chloride in good yield and high purity.
Polystyrene-supported 4-(phenylseleno)morpholine was synthesized and could be used as an efficient α-selenenylating agent for saturated aldehydes.α-Haloaldehydes were prepared by reaction of polystyrene-supported α-selenoaldehydes with bromine or sulfuryl chloride in good yield and high purity.
2003, 14(5): 459-460
Abstract:
In the presence of NaBH4/BF3, allyl ethers underwent deallylation to the corresponding alcohols or phenols in good yield and high reaction rate.
In the presence of NaBH4/BF3, allyl ethers underwent deallylation to the corresponding alcohols or phenols in good yield and high reaction rate.
2003, 14(5): 461-464
Abstract:
Diphenyl oxalate was synthesized from transesterification of dimethyl oxalate with phenol over TS-1( 2.5 wt% Ti ) catalyst.TS-1 catalyst, as a heterogeneous catalyst, showed excellent selectivity of diphenyl oxalate and methylphenyl oxalate compared with other homogeneous catalysts.Lewis acid sites on TS-1 catalyst were the active sites for transesterification of dimethyl oxalate with phenol.The high selectivity was closely related to the weak acid sites over TS-1.
Diphenyl oxalate was synthesized from transesterification of dimethyl oxalate with phenol over TS-1( 2.5 wt% Ti ) catalyst.TS-1 catalyst, as a heterogeneous catalyst, showed excellent selectivity of diphenyl oxalate and methylphenyl oxalate compared with other homogeneous catalysts.Lewis acid sites on TS-1 catalyst were the active sites for transesterification of dimethyl oxalate with phenol.The high selectivity was closely related to the weak acid sites over TS-1.
2003, 14(5): 465-467
Abstract:
The preparation of carbosilane dendrimers with cores of myo-inositol and the outmost periphery groups of allyl groups has been reported.By using alternate hydrosilylation and alkenylation reactions, the dendrimer have been carried up to the third generation with 48 allyl groups on the periphery.
The preparation of carbosilane dendrimers with cores of myo-inositol and the outmost periphery groups of allyl groups has been reported.By using alternate hydrosilylation and alkenylation reactions, the dendrimer have been carried up to the third generation with 48 allyl groups on the periphery.
2003, 14(5): 468-470
Abstract:
A new approach to synthesis of 6,7-dimethoxyisatin is reported.2-nitro-3, 4-dimethoxy mandelonitrile in glacial acetic acid was treated with the solution of stannous chloride in hydrochloric acid to give 6, 7-dimethoxyisatin in a high yield.
A new approach to synthesis of 6,7-dimethoxyisatin is reported.2-nitro-3, 4-dimethoxy mandelonitrile in glacial acetic acid was treated with the solution of stannous chloride in hydrochloric acid to give 6, 7-dimethoxyisatin in a high yield.
2003, 14(5): 471-474
Abstract:
A series of β-aromatic amino substituted triazolyl ketenes were reduced at different conditions to enols and saturated alcohols, respectively.The preliminary biological tests showed that some of them exhibit good fungicidal activities.
A series of β-aromatic amino substituted triazolyl ketenes were reduced at different conditions to enols and saturated alcohols, respectively.The preliminary biological tests showed that some of them exhibit good fungicidal activities.
2003, 14(5): 475-478
Abstract:
From rhizomes of Hemsleya giganthy collected in Shichuan of China, 16 compounds were isolated.Among them, three compounds (8, 9, 15) are new natural products called Hemslecins G; Hemsgiganosides A and B; respectively.Their structures were elucidated as 7-hydroxy-23, 24-dihydro-cucurbitacin F-25-O-acetate (8); 3-O-(6'-butyl ester-)-β-D-glu-curono-pyranosyl)-oleanolic acid-28-O-α-L-arabinopyranoside(9); 3-O-β-D-glucuropyranosyl oleanolic acid-28-O-β-D-gluco pyranosyl-(1→6)-β-D-glucopyranoside(15) by spectroscopic and chemical means.
From rhizomes of Hemsleya giganthy collected in Shichuan of China, 16 compounds were isolated.Among them, three compounds (8, 9, 15) are new natural products called Hemslecins G; Hemsgiganosides A and B; respectively.Their structures were elucidated as 7-hydroxy-23, 24-dihydro-cucurbitacin F-25-O-acetate (8); 3-O-(6'-butyl ester-)-β-D-glu-curono-pyranosyl)-oleanolic acid-28-O-α-L-arabinopyranoside(9); 3-O-β-D-glucuropyranosyl oleanolic acid-28-O-β-D-gluco pyranosyl-(1→6)-β-D-glucopyranoside(15) by spectroscopic and chemical means.
2003, 14(5): 479-482
Abstract:
Two new eremophilenolides (3β-angeloyloxy-8β, 10β-dihydroxy-6β-ethoxyeremophile-nolide (1) and 3β, 6β-diangeloyloxy-8α-methoxy-10α-hydroxyeremophilenolide (2) were isolated from the roots of Cacalia ainsliaeflora.Their structures were elucidated by spectroscopic methods.
Two new eremophilenolides (3β-angeloyloxy-8β, 10β-dihydroxy-6β-ethoxyeremophile-nolide (1) and 3β, 6β-diangeloyloxy-8α-methoxy-10α-hydroxyeremophilenolide (2) were isolated from the roots of Cacalia ainsliaeflora.Their structures were elucidated by spectroscopic methods.
2003, 14(5): 483-484
Abstract:
A new xanthanolide was isolated from the aerial parts of Carpesium longifolium.It's structure was elucidated as 1β, 4β-epoxy-5β-hydroxy-10αH-xantha-11(13)-en-12, 8β-olide by spectral methods (HRMS, 1D and 2D NMR).
A new xanthanolide was isolated from the aerial parts of Carpesium longifolium.It's structure was elucidated as 1β, 4β-epoxy-5β-hydroxy-10αH-xantha-11(13)-en-12, 8β-olide by spectral methods (HRMS, 1D and 2D NMR).
2003, 14(5): 485-486
Abstract:
Two new sesquiterpenes were isolated from the aerial parts of Inula japonica.Their structures were elucidated as 1β-hydroxy-8β-acetoxycostic acid methyl ester and 1β-hydroxy-8β-acetoxyisocostic acid methyl ester by spectral methods.
Two new sesquiterpenes were isolated from the aerial parts of Inula japonica.Their structures were elucidated as 1β-hydroxy-8β-acetoxycostic acid methyl ester and 1β-hydroxy-8β-acetoxyisocostic acid methyl ester by spectral methods.
2003, 14(5): 487-488
Abstract:
Two new styryllactones, iso-goniopypyrone and 8-acetyl-9-deoxygoniopypyrone, were isolated from the roots of Goniothalamus cheliensis.Their structure were elucidated on the basis of spectroscopic and chemical evidences
Two new styryllactones, iso-goniopypyrone and 8-acetyl-9-deoxygoniopypyrone, were isolated from the roots of Goniothalamus cheliensis.Their structure were elucidated on the basis of spectroscopic and chemical evidences
2003, 14(5): 489-490
Abstract:
A new compound, 4-hydroxy-α-tetralone-4-O-β-D-[6'-O-(3",4",5"-trihydroxybenzoyl) glucopyranoside (1), together with a known compound, 4-hydroxy-α-tetralone (2), has been isolated from the roots of Juglans regia.2 showed moderate bioactivity against protein tyrosine phosphatase 1B (PTP1B).
A new compound, 4-hydroxy-α-tetralone-4-O-β-D-[6'-O-(3",4",5"-trihydroxybenzoyl) glucopyranoside (1), together with a known compound, 4-hydroxy-α-tetralone (2), has been isolated from the roots of Juglans regia.2 showed moderate bioactivity against protein tyrosine phosphatase 1B (PTP1B).
2003, 14(5): 491-494
Abstract:
Two new spirostanol sapogenins named agavegenin A and B were isolated from the fermented leaves of Agave americana L. Their structures were elucidated as (23S, 25R)-5α-spirostan-3β, 6α, 11α, 23-tetraol (1) and (23S, 25S)-5α-spirostan-3β, 23, 27-triol (2) by spectral methods.
Two new spirostanol sapogenins named agavegenin A and B were isolated from the fermented leaves of Agave americana L. Their structures were elucidated as (23S, 25R)-5α-spirostan-3β, 6α, 11α, 23-tetraol (1) and (23S, 25S)-5α-spirostan-3β, 23, 27-triol (2) by spectral methods.
2003, 14(5): 495-498
Abstract:
The intramolecular charge transfer dual fluorescence of p-dibutylaminobenzoic acid-β-cyclodextrin inclusion complex showed a substantially higher sensitivity toward aqueous solution pH variation when compared with that of p-dibutylaminobenzoic acid alone, which established a new principle for direct CT fluorescence sensing in aqueous solution by using the CT fluorophore-cyclodextrin inclusion complex.
The intramolecular charge transfer dual fluorescence of p-dibutylaminobenzoic acid-β-cyclodextrin inclusion complex showed a substantially higher sensitivity toward aqueous solution pH variation when compared with that of p-dibutylaminobenzoic acid alone, which established a new principle for direct CT fluorescence sensing in aqueous solution by using the CT fluorophore-cyclodextrin inclusion complex.
2003, 14(5): 499-502
Abstract:
Positive ion ESI-MS has been used to examine the fragmentation pathways of the complex ions of deoxydinucleotides with H+, Na+, K+ by LCQ instrument.It had been found that the dissociation varied markedly due to the differences of the base sequence.The alkali-metal ion binding site and the characterization of dissociation were directed by the size of metal ion, the sequence of base and the steric hindrance.
Positive ion ESI-MS has been used to examine the fragmentation pathways of the complex ions of deoxydinucleotides with H+, Na+, K+ by LCQ instrument.It had been found that the dissociation varied markedly due to the differences of the base sequence.The alkali-metal ion binding site and the characterization of dissociation were directed by the size of metal ion, the sequence of base and the steric hindrance.
2003, 14(5): 503-504
Abstract:
Using continuous wavelet transform as the analytical tool, the fractal characteristic of nucleotide sequences was studied.The fractal dimension of the exon and intron sequences for different species was calculated.We use the Mexican hat wavelet function as the mother wavelet and Hurst exponent to describe the long-range correlation.It is found that the Hurst exponent of intron sequence is larger than that of exon sequence for the same gene.
Using continuous wavelet transform as the analytical tool, the fractal characteristic of nucleotide sequences was studied.The fractal dimension of the exon and intron sequences for different species was calculated.We use the Mexican hat wavelet function as the mother wavelet and Hurst exponent to describe the long-range correlation.It is found that the Hurst exponent of intron sequence is larger than that of exon sequence for the same gene.
2003, 14(5): 505-508
Abstract:
The bleaching of indigo-carmine catalyzed by laccase was monitored on-line by UV/Vis spectroscopy.The resulted data were analyzed by evolving factor analysis (EFA) and multivariate curve resolution (MCR), and the reaction mechanism was proposed.
The bleaching of indigo-carmine catalyzed by laccase was monitored on-line by UV/Vis spectroscopy.The resulted data were analyzed by evolving factor analysis (EFA) and multivariate curve resolution (MCR), and the reaction mechanism was proposed.
2003, 14(5): 509-512
Abstract:
Two charge-transfer complexes of 2a and 2b of Keggin type were synthesized and characterized by elemental analysis, IR spectra, UV spectra, XRD, TG-DSC; and were compared with Hquin-PW12.The primary structure of the heteropolyanions had not been changed after the formation of the charge transfer complexes.
Two charge-transfer complexes of 2a and 2b of Keggin type were synthesized and characterized by elemental analysis, IR spectra, UV spectra, XRD, TG-DSC; and were compared with Hquin-PW12.The primary structure of the heteropolyanions had not been changed after the formation of the charge transfer complexes.
2003, 14(5): 513-514
Abstract:
Hybrid self-assembled multilayer films were prepared by alternate adsorption of 1,10-diaminodecane (1,10-DAD) and Keggin polyoxometalates of SiW12O404-, SiW11VO405-, and PMo12O403-, respectively.The films were reproducibly grown at each adsorption cycle as monitored by UV spectroscopy.
Hybrid self-assembled multilayer films were prepared by alternate adsorption of 1,10-diaminodecane (1,10-DAD) and Keggin polyoxometalates of SiW12O404-, SiW11VO405-, and PMo12O403-, respectively.The films were reproducibly grown at each adsorption cycle as monitored by UV spectroscopy.
2003, 14(5): 515-518
Abstract:
The title compounds 2a-c were synthesized and characterized for the first time.Their proton numbers are around 3.2±0.15 and are not in proportion with the valid acidity-basicity of the central phosphonic acids.The entirety of phosphonic acids 1a-c is as the coordinate center of heteropoly anions of 2a-c.
The title compounds 2a-c were synthesized and characterized for the first time.Their proton numbers are around 3.2±0.15 and are not in proportion with the valid acidity-basicity of the central phosphonic acids.The entirety of phosphonic acids 1a-c is as the coordinate center of heteropoly anions of 2a-c.
2003, 14(5): 519-522
Abstract:
The synthesis and crystal structure of oxo-centered carboxylate-bridge trinuclear ruthenium complex, Ru3O(CH3COO)6(py)2Cl (py =pyridine) (1), are reported herein.The complex 1 has been characterized by IR, cyclic voltammetry (CV), UV-Vis and X-ray crystal analysis.The complex 1 in 0.1 mol/L (n-C4H9)4NPF6-CH2Cl2 solution at room temperature shows four one-electron redox processes at E1/2=-1.38,-1.20,-0.17 and 1.07 V vs.Ag/AgCl.
The synthesis and crystal structure of oxo-centered carboxylate-bridge trinuclear ruthenium complex, Ru3O(CH3COO)6(py)2Cl (py =pyridine) (1), are reported herein.The complex 1 has been characterized by IR, cyclic voltammetry (CV), UV-Vis and X-ray crystal analysis.The complex 1 in 0.1 mol/L (n-C4H9)4NPF6-CH2Cl2 solution at room temperature shows four one-electron redox processes at E1/2=-1.38,-1.20,-0.17 and 1.07 V vs.Ag/AgCl.
2003, 14(5): 523-524
Abstract:
A new type of ionic liquids containing cation of diacetone acrylamide [or N-(1,1-bismethyl-3-oxo-butyl)acrylamide] and anions such as CH3COO-(Ac), CF3COO(-(TF), BF4-(BF), PF6-(PF), HSO4-(SO) and Cl-(Cl) were prepared by normal neutralization.The obtained ionic liquids were identified by FT-IR and 1H NMR spectroscopy.However, their properties such as melting point, conductivity, viscosity etc.were determined.
A new type of ionic liquids containing cation of diacetone acrylamide [or N-(1,1-bismethyl-3-oxo-butyl)acrylamide] and anions such as CH3COO-(Ac), CF3COO(-(TF), BF4-(BF), PF6-(PF), HSO4-(SO) and Cl-(Cl) were prepared by normal neutralization.The obtained ionic liquids were identified by FT-IR and 1H NMR spectroscopy.However, their properties such as melting point, conductivity, viscosity etc.were determined.
2003, 14(5): 525-528
Abstract:
A new ligand, 10-ethylphenothiazinyl-3-yl-methylene thiosemicarbazon (HL) and its complexes ML2(M=Zn2+, Cd2+), which exhibit intensive two-photon excited (TPE) fluorescence at 800 nm laser pulses in femtosecond regime, were synthesized and characterized.The measured power dependence of the fluorescence signals provided direct evidence for TPE.All of them exhibited a large two-photon absorptive cross section and, more importantly from the application point of view, high photochemical/photothermal stability.
A new ligand, 10-ethylphenothiazinyl-3-yl-methylene thiosemicarbazon (HL) and its complexes ML2(M=Zn2+, Cd2+), which exhibit intensive two-photon excited (TPE) fluorescence at 800 nm laser pulses in femtosecond regime, were synthesized and characterized.The measured power dependence of the fluorescence signals provided direct evidence for TPE.All of them exhibited a large two-photon absorptive cross section and, more importantly from the application point of view, high photochemical/photothermal stability.
2003, 14(5): 529-532
Abstract:
The metabolic mechanism of 8-hydroxyguanine (8-OHGua) is so far unknown, however it is known to function in the mutagenic events in biological systems.In the present study, the metabolic processes is investigated by the reaction of 8-OHGua with PRPP catalyzed by HGPRT and Mg(Ⅱ).The evidence shows that the interaction between 8-OHGua and the enzyme is indeed taken place and 8-OHGMP is formed.
The metabolic mechanism of 8-hydroxyguanine (8-OHGua) is so far unknown, however it is known to function in the mutagenic events in biological systems.In the present study, the metabolic processes is investigated by the reaction of 8-OHGua with PRPP catalyzed by HGPRT and Mg(Ⅱ).The evidence shows that the interaction between 8-OHGua and the enzyme is indeed taken place and 8-OHGMP is formed.
2003, 14(5): 533-534
Abstract:
A new preparation and reduction method of γ-Al2O3 supported and PVP stabilized platinum nanoclusters was studied.The catalyst exhibited very high activity and selectivity for acetophenone hydrogenation in isopropanol-KOH solution at 25~60℃ and PH2=1~5 MPa.
A new preparation and reduction method of γ-Al2O3 supported and PVP stabilized platinum nanoclusters was studied.The catalyst exhibited very high activity and selectivity for acetophenone hydrogenation in isopropanol-KOH solution at 25~60℃ and PH2=1~5 MPa.
2003, 14(5): 535-538
Abstract:
Investigations of the absorption and fluorescence spectra of hexakis (4-aminophenoxy)-cyclotriphosphazene at room temperature in three solvents of different polarity (N, N-dimethyl-formamide, tetrahydrofuran and toluene) have been conducted.And fluorescence lifetimes of these three solutions were also measured.Major reasons of such spectral behavior are discussed
Investigations of the absorption and fluorescence spectra of hexakis (4-aminophenoxy)-cyclotriphosphazene at room temperature in three solvents of different polarity (N, N-dimethyl-formamide, tetrahydrofuran and toluene) have been conducted.And fluorescence lifetimes of these three solutions were also measured.Major reasons of such spectral behavior are discussed
2003, 14(5): 539-542
Abstract:
Ag-TiO2/ITO film electrode was used as photoanode to investigate the feasibility of a hybrid technology of Ag nanoparticles combined with the application of anodic bias.The results showed that the deposited Ag and applied anodic bias have an apparent additive effect.
Ag-TiO2/ITO film electrode was used as photoanode to investigate the feasibility of a hybrid technology of Ag nanoparticles combined with the application of anodic bias.The results showed that the deposited Ag and applied anodic bias have an apparent additive effect.
2003, 14(5): 543-546
Abstract:
The SEM and AFM images of three TiO2 nano-films prepared at different conditions were obtained and transformed into digital format.The multifractal analyses for three films were made using height from a depth of thickness of film B and q from 55 to-55.The scale-invariance is very good for all lnχq(ε)~lnε plots and τ(q)~q plots at least close to three orders of magnitude.But the multifractal spectra f(a) of the films are quite distinct due to their different height distribution.
The SEM and AFM images of three TiO2 nano-films prepared at different conditions were obtained and transformed into digital format.The multifractal analyses for three films were made using height from a depth of thickness of film B and q from 55 to-55.The scale-invariance is very good for all lnχq(ε)~lnε plots and τ(q)~q plots at least close to three orders of magnitude.But the multifractal spectra f(a) of the films are quite distinct due to their different height distribution.
2003, 14(5): 547-550
Abstract:
Two new D-π-A type compounds, where electron-donor D is tertiary amino group, electron-acceptor A is 2-benzothiazolyl and π is two conjugated styryl units, have been synthesized.They are named as trans, trans-2-{4-[4-(N, N-diethylamino)styryl]styryl}-1, 3-benzothiazole and trans, trans-2-{4-[4-(N, N-diphenylamino)styryl]styryl}-1, 3-benzothiazole.Both compounds show strong two-photon excited fluorescence in yellow-orange region when excited by a femtosecond laser at 800 nm.
Two new D-π-A type compounds, where electron-donor D is tertiary amino group, electron-acceptor A is 2-benzothiazolyl and π is two conjugated styryl units, have been synthesized.They are named as trans, trans-2-{4-[4-(N, N-diethylamino)styryl]styryl}-1, 3-benzothiazole and trans, trans-2-{4-[4-(N, N-diphenylamino)styryl]styryl}-1, 3-benzothiazole.Both compounds show strong two-photon excited fluorescence in yellow-orange region when excited by a femtosecond laser at 800 nm.
