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2002 Volume 13 Issue 3
2002, 13(3): 189-192
Abstract:
The reactions of 3,7-dinitrodibenzobromolium salt with some amines were studied. A reaction mechanism based on the structure of the major product 6 and the minor product 7 was proposed. The reaction was considered to proceed via a substituted benzyene intermediate.
The reactions of 3,7-dinitrodibenzobromolium salt with some amines were studied. A reaction mechanism based on the structure of the major product 6 and the minor product 7 was proposed. The reaction was considered to proceed via a substituted benzyene intermediate.
2002, 13(3): 193-194
Abstract:
The solid phase synthesis of 4 (1H) quinolones has been reported.
The solid phase synthesis of 4 (1H) quinolones has been reported.
2002, 13(3): 195-198
Abstract:
A new method for synthesis of 3-azido-3-deoxyxylofuranoside was described. D-ribose was methylated, then treated with methanesulfonyl chloride to give Ⅱ. Ⅱ was selectively replaced by benzoate at the 5-position to give Ⅲ. All these processes gave good yields. Ⅲ was treated with sodium azide to afford Ⅳ, whose structure was determined by 1H NMR and 13C NMR.
A new method for synthesis of 3-azido-3-deoxyxylofuranoside was described. D-ribose was methylated, then treated with methanesulfonyl chloride to give Ⅱ. Ⅱ was selectively replaced by benzoate at the 5-position to give Ⅲ. All these processes gave good yields. Ⅲ was treated with sodium azide to afford Ⅳ, whose structure was determined by 1H NMR and 13C NMR.
2002, 13(3): 199-200
Abstract:
Some dehydropeptide analogues were directly synthesized by the reaction of unsaturated oxazolones with free amino acids.
Some dehydropeptide analogues were directly synthesized by the reaction of unsaturated oxazolones with free amino acids.
2002, 13(3): 201-204
Abstract:
Total synthesis of two cytotoxic natural products, nelumol A (1) and nelumal A (2), were carried out by two different paths. 4-O-Benzyl substitute analogues 26 and 27, as well as the 4-O-(2-methyl-butenyl) derivatives 29 and 30 were also synthesized for a SAR investigation. 1 and 2 were also measured on different tumor cell line.
Total synthesis of two cytotoxic natural products, nelumol A (1) and nelumal A (2), were carried out by two different paths. 4-O-Benzyl substitute analogues 26 and 27, as well as the 4-O-(2-methyl-butenyl) derivatives 29 and 30 were also synthesized for a SAR investigation. 1 and 2 were also measured on different tumor cell line.
2002, 13(3): 205-206
Abstract:
By 1,4-bridging of p-tert-butylcalix [6] arene with 2,6-bis (bromomethyl)-4-methyl-anisole, a new type of bis-calix [5] arene analogue was obtained in high yield..
By 1,4-bridging of p-tert-butylcalix [6] arene with 2,6-bis (bromomethyl)-4-methyl-anisole, a new type of bis-calix [5] arene analogue was obtained in high yield..
2002, 13(3): 207-210
Abstract:
The condensation reaction between 5-amino-4, 6-dichloro-2-methylpyrimidine and 1-acetyl-2-imidazolin-2-one using POCl3 as solvent gave 4, 6-dichloro-2-methyl-5-(l-acetyl-tetrahydro-imidazo-2-ylidene)-aminopyrimidine predominantly and 4, 6-dichloro-2-methyl-5-{1-[ l-(2-oxo-tetrahydro-imidazolyl)]-acetyene}-aminopyrimidine as by-product. No 4, 6-dichloro-2-methyl-5-(1-acetyl-2-imidazolin-2-yl)-aminopyrimidine was found. The result indicated an esterifi-cation-addition-elimination mechanism.
The condensation reaction between 5-amino-4, 6-dichloro-2-methylpyrimidine and 1-acetyl-2-imidazolin-2-one using POCl3 as solvent gave 4, 6-dichloro-2-methyl-5-(l-acetyl-tetrahydro-imidazo-2-ylidene)-aminopyrimidine predominantly and 4, 6-dichloro-2-methyl-5-{1-[ l-(2-oxo-tetrahydro-imidazolyl)]-acetyene}-aminopyrimidine as by-product. No 4, 6-dichloro-2-methyl-5-(1-acetyl-2-imidazolin-2-yl)-aminopyrimidine was found. The result indicated an esterifi-cation-addition-elimination mechanism.
2002, 13(3): 211-212
Abstract:
Copper supported over silica exhibited very high activity and selectivity for the direct synthesis of indole at atmospheric pressure. Under the reaction temperature of 325℃,the yield of indole could obtain 88%.
Copper supported over silica exhibited very high activity and selectivity for the direct synthesis of indole at atmospheric pressure. Under the reaction temperature of 325℃,the yield of indole could obtain 88%.
2002, 13(3): 213-214
Abstract:
Chitosans reacted with selenious acid to prepare chitosan hydrogen selenites, which were found to be growth-inhibitory against sarcoma 180 solid tumor. The results indicated that the activity also depended on the molecular weight of chitosan supports.
Chitosans reacted with selenious acid to prepare chitosan hydrogen selenites, which were found to be growth-inhibitory against sarcoma 180 solid tumor. The results indicated that the activity also depended on the molecular weight of chitosan supports.
2002, 13(3): 215-216
Abstract:
Monoclonal antibody technique was employed to detect the conformational difference of CaM induced by metal ions. A trivalent europium ion induced conformation-specific anti-calmodulin monoclonal antibody was successfully prepared with europium-saturated calmodulin as antigen.
Monoclonal antibody technique was employed to detect the conformational difference of CaM induced by metal ions. A trivalent europium ion induced conformation-specific anti-calmodulin monoclonal antibody was successfully prepared with europium-saturated calmodulin as antigen.
2002, 13(3): 217-218
Abstract:
The design and synthesis of novel dendritic-linear block copolymers were described. The copolymers were synthesized by atom transfer radical polymerization (ATRP) using dendritic polyarylether 2-bromoisobutyrate macroinitiator. ATRP carried out in bulk with CuBr/bipy catalyst at 120℃, yielded well-defined block copolymers with polydispersities less than 1.36.
The design and synthesis of novel dendritic-linear block copolymers were described. The copolymers were synthesized by atom transfer radical polymerization (ATRP) using dendritic polyarylether 2-bromoisobutyrate macroinitiator. ATRP carried out in bulk with CuBr/bipy catalyst at 120℃, yielded well-defined block copolymers with polydispersities less than 1.36.
2002, 13(3): 219-222
Abstract:
The polystyrenylphosphonous acid (PSPA) of low polymerization degree was prepared with one step reaction. The reaction mechanism was changed with different initiators. For the reaction with AIBN or BPO as the initiator, there are 2 or 3 series of radical reaction chains and 5 or 9 series of polystyrenyl products. The main products are PSPA without or with the fragment of the initiator H[CH(C6H5)-CH2]n-PO2H2 and C6H5CO2-[CH2CH (C6H5)]n-PO2H2 respectively.
The polystyrenylphosphonous acid (PSPA) of low polymerization degree was prepared with one step reaction. The reaction mechanism was changed with different initiators. For the reaction with AIBN or BPO as the initiator, there are 2 or 3 series of radical reaction chains and 5 or 9 series of polystyrenyl products. The main products are PSPA without or with the fragment of the initiator H[CH(C6H5)-CH2]n-PO2H2 and C6H5CO2-[CH2CH (C6H5)]n-PO2H2 respectively.
2002, 13(3): 223-226
Abstract:
The cleavage of DNA (pUC18) by lipophilic macrocyclic polyamine Co(Ⅱ) complex was investigated in metallomicellar system. The results showed that the conversion of plasmid DNA (pUC18) increases with the increase of the concentration of complex under physiological conditions.
The cleavage of DNA (pUC18) by lipophilic macrocyclic polyamine Co(Ⅱ) complex was investigated in metallomicellar system. The results showed that the conversion of plasmid DNA (pUC18) increases with the increase of the concentration of complex under physiological conditions.
2002, 13(3): 227-230
Abstract:
The inclusion complex of lappaconitine (Lap) with β-cyclodextrin (β-CD) has been studied by the differential scanning calorimetry (DSC) and 1H-NMR, 2D-NMR spectroscopy.The structure of the complex has been deduced.
The inclusion complex of lappaconitine (Lap) with β-cyclodextrin (β-CD) has been studied by the differential scanning calorimetry (DSC) and 1H-NMR, 2D-NMR spectroscopy.The structure of the complex has been deduced.
2002, 13(3): 231-232
Abstract:
A new compound was isolated from Bletilla striata. Its structure was elucidated as 5-hydroxy-4-(p-hydroxybenzyl)-3', 3-dimethoxybibenzyl by spectroscopic method.
A new compound was isolated from Bletilla striata. Its structure was elucidated as 5-hydroxy-4-(p-hydroxybenzyl)-3', 3-dimethoxybibenzyl by spectroscopic method.
2002, 13(3): 233-236
Abstract:
In continuation of our studies on Aconitum hemsleyanum Pritz. var. pengzhouense, two new norditerpenoid alkaloids, pengshenines A (1) and B (2), have been isolated from the roots of the plants and their structures were elucidated by 1D-and 2D-NMR.
In continuation of our studies on Aconitum hemsleyanum Pritz. var. pengzhouense, two new norditerpenoid alkaloids, pengshenines A (1) and B (2), have been isolated from the roots of the plants and their structures were elucidated by 1D-and 2D-NMR.
2002, 13(3): 237-240
Abstract:
Two new phenolic glycosides, everninic acid methyl ester-2-O-β-D-xylopyran-osyl-(16)-β-D-glucopyranoside 1 and 7-hydroxy-5-methoxyphthalide-7-β-D-xylopyranosyl-(1→6)-β-D-glucopyranoside 2 were isolated from the roots of Rhododendron molle G. Don. Their structures were determined by spectral evidence including 2D NMR techniques.
Two new phenolic glycosides, everninic acid methyl ester-2-O-β-D-xylopyran-osyl-(16)-β-D-glucopyranoside 1 and 7-hydroxy-5-methoxyphthalide-7-β-D-xylopyranosyl-(1→6)-β-D-glucopyranoside 2 were isolated from the roots of Rhododendron molle G. Don. Their structures were determined by spectral evidence including 2D NMR techniques.
2002, 13(3): 241-244
Abstract:
A new furostanol saponin presenting moderate bioactivity of inducing morphological deformation of Pyricularia oryzae mycelia was isolated from Dioscorea futshauensis R.Kunth by bioactivity-guided fractionation. The structure was established as 26-O-β-D-glucopyranosyl-3β, 26-diol-23(S)-methoxyl-(25R)-furost-5,20 (22)-diene-3-O-[α-L-rhamnopyranosyl (1→2)-b-D-glucopyranosyl (1→3)]-β-D-glucopyranoside on the basis of chemical evidencesand spectral analysis, especially by 2D-NMR techniques.
A new furostanol saponin presenting moderate bioactivity of inducing morphological deformation of Pyricularia oryzae mycelia was isolated from Dioscorea futshauensis R.Kunth by bioactivity-guided fractionation. The structure was established as 26-O-β-D-glucopyranosyl-3β, 26-diol-23(S)-methoxyl-(25R)-furost-5,20 (22)-diene-3-O-[α-L-rhamnopyranosyl (1→2)-b-D-glucopyranosyl (1→3)]-β-D-glucopyranoside on the basis of chemical evidencesand spectral analysis, especially by 2D-NMR techniques.
2002, 13(3): 245-246
Abstract:
A new phytosterone named cyanosterone B (1) has been isolated from Cyanotis arachnoidea C. B. Clarke. The structure of cyanosterone B was elucidated as 3β, 5β, 14α, 20R, 22R-pentahydroxy-cholest-7-en-6-one on the basis of spectroscopic analysis.
A new phytosterone named cyanosterone B (1) has been isolated from Cyanotis arachnoidea C. B. Clarke. The structure of cyanosterone B was elucidated as 3β, 5β, 14α, 20R, 22R-pentahydroxy-cholest-7-en-6-one on the basis of spectroscopic analysis.
2002, 13(3): 247-248
Abstract:
Two new sesquiterpene lactone glycosides were isolated from the seeds of Carpesium macrocephalum. Their structures were elucidated as 2α-O-β-D-glucopyranosy-5α, 11αH-eudesma-4 (15)-en-12, 8β-olide and 2α-O-β-D-glucopyranosy-5αH-eudesma-4(15), 11 (13)-dien-12, 8β-olide by spectral methods (HRMS, ID and 2D NMR).
Two new sesquiterpene lactone glycosides were isolated from the seeds of Carpesium macrocephalum. Their structures were elucidated as 2α-O-β-D-glucopyranosy-5α, 11αH-eudesma-4 (15)-en-12, 8β-olide and 2α-O-β-D-glucopyranosy-5αH-eudesma-4(15), 11 (13)-dien-12, 8β-olide by spectral methods (HRMS, ID and 2D NMR).
2002, 13(3): 249-250
Abstract:
From the roots of Ligularia macrophylla,a bisesquiterpene,ligumacrophyllal was isolated and its structure was elucidated on the basis of spectroscopic methods.
From the roots of Ligularia macrophylla,a bisesquiterpene,ligumacrophyllal was isolated and its structure was elucidated on the basis of spectroscopic methods.
2002, 13(3): 251-252
Abstract:
One new triterpenoid saponin, monepaloside K (1) was isolated from the water-soluble part of the whole plant of a famous Tibetan medicinal herb, morina nepalensis var. alba Hand.-Mazz.. Its structure was determined to be 3-O-α-L-arabinopyranosyl-(1→3)-β-D-xylopyranosyl siaresinolic acid on the basis of spectroscopic evidences, especially 2D NMR techniques.
One new triterpenoid saponin, monepaloside K (1) was isolated from the water-soluble part of the whole plant of a famous Tibetan medicinal herb, morina nepalensis var. alba Hand.-Mazz.. Its structure was determined to be 3-O-α-L-arabinopyranosyl-(1→3)-β-D-xylopyranosyl siaresinolic acid on the basis of spectroscopic evidences, especially 2D NMR techniques.
2002, 13(3): 253-255
Abstract:
Two new triterpenoid glycosides, hederagenin-3-O-β-D-xylopyranoside (1), dodecandral 3-O-β-D-xylopyranoside(2), were isolated from Elsholtzia bodinieri Van't. The structures of 1 and 2 were established by spectroscopic and chemical methods.
Two new triterpenoid glycosides, hederagenin-3-O-β-D-xylopyranoside (1), dodecandral 3-O-β-D-xylopyranoside(2), were isolated from Elsholtzia bodinieri Van't. The structures of 1 and 2 were established by spectroscopic and chemical methods.
2002, 13(3): 256-257
Abstract:
A novel alternating conjugated copolymer containing triazole and carbazole units was synthesized by the Wittig reaction. The resulting bipolar conjugated polymer emits a pure light with good thermal stability, which is a promising candidate for polymer light emitting display.
A novel alternating conjugated copolymer containing triazole and carbazole units was synthesized by the Wittig reaction. The resulting bipolar conjugated polymer emits a pure light with good thermal stability, which is a promising candidate for polymer light emitting display.
2002, 13(3): 258-261
Abstract:
Two-dimensional nuclear overhauser enhancement (2D NOESY) measurements show that sodium dodecyl sulfonate SDSN molecules co-aggregate with poly-ethylene glycol PEG in their aqueous solution at a concentration range of SDSN between the so-called co-aggregation concentration (cac) and the normal critical micellar concentration (cmc). SDSN micelles are formed when the cmc of SDSN is reached with PEG uniformly distributed in the interior.
Two-dimensional nuclear overhauser enhancement (2D NOESY) measurements show that sodium dodecyl sulfonate SDSN molecules co-aggregate with poly-ethylene glycol PEG in their aqueous solution at a concentration range of SDSN between the so-called co-aggregation concentration (cac) and the normal critical micellar concentration (cmc). SDSN micelles are formed when the cmc of SDSN is reached with PEG uniformly distributed in the interior.
2002, 13(3): 262-265
Abstract:
The adsorption of bovine serum albumin (BSA) on porous polyethylene (PE) membrane was studied based on adsorption and desorption measurements as well as FTIR analysis. A different mechanism was proposed which showed that a critical concentration existed in the adsorptional process. Below this concentration, the adsorption seems to be conducted in a normal side-on way; above this concentration, the adsorption is in an aggregation way.
The adsorption of bovine serum albumin (BSA) on porous polyethylene (PE) membrane was studied based on adsorption and desorption measurements as well as FTIR analysis. A different mechanism was proposed which showed that a critical concentration existed in the adsorptional process. Below this concentration, the adsorption seems to be conducted in a normal side-on way; above this concentration, the adsorption is in an aggregation way.
2002, 13(3): 266-268
Abstract:
Aniline oligomer composite materials using heteropolyacid H4SiW12O40 as dopant was synthesized, and the effect of the doping concentration on the photoluminescence and surface photovoltaic properties were investigated.
Aniline oligomer composite materials using heteropolyacid H4SiW12O40 as dopant was synthesized, and the effect of the doping concentration on the photoluminescence and surface photovoltaic properties were investigated.
2002, 13(3): 269-272
Abstract:
A capillary electrophoresis (CE) method has been firstly used for the separation of the therapeutically important xanthones from Securidaca inappendiculata. The separation of the nine xanthones was systematically optimized with respect to pH, concentration of running buffers, addition of sulfated β-CD, applied voltage and column temperature. Baseline separation was achieved for the nine xanthones in less than 15 minutes using a background electrolyte consisting of 200 mmol/L borate (pH 9.5) and 10 mmol/L sulfated β-CD.
A capillary electrophoresis (CE) method has been firstly used for the separation of the therapeutically important xanthones from Securidaca inappendiculata. The separation of the nine xanthones was systematically optimized with respect to pH, concentration of running buffers, addition of sulfated β-CD, applied voltage and column temperature. Baseline separation was achieved for the nine xanthones in less than 15 minutes using a background electrolyte consisting of 200 mmol/L borate (pH 9.5) and 10 mmol/L sulfated β-CD.
2002, 13(3): 273-276
Abstract:
A novel micro-hole electrode was fabricated to investigate the electron transfer reaction at the interface between two immiscible electrolyte solutions (ITIES). The electron transfer reaction between ferro/ferricyanide in aqueous phase (W) and ferrocene in 1, 2-dichloroethane (O) phase was studied as a test experiment. The results showed that the diffusion coefficient obtained from the micro-hole electrode was consistent with that obtained at macro-interface. Due to its simplicity and the very small IR drop it will be a useful tool for the study of ITIES systems.
A novel micro-hole electrode was fabricated to investigate the electron transfer reaction at the interface between two immiscible electrolyte solutions (ITIES). The electron transfer reaction between ferro/ferricyanide in aqueous phase (W) and ferrocene in 1, 2-dichloroethane (O) phase was studied as a test experiment. The results showed that the diffusion coefficient obtained from the micro-hole electrode was consistent with that obtained at macro-interface. Due to its simplicity and the very small IR drop it will be a useful tool for the study of ITIES systems.
2002, 13(3): 277-278
Abstract:
Potential oscillation during the electrocatalytic oxidation of methanol can be modulated by the specific adsorption of Cl- on the platinum electrode, which suppresses the electrocatalytic oxidation of methanol, and makes the cross cycle in the cyclic voltammogram become smaller and finally disappear with the increase of Cl- concentration. The method is also applicable to the electrocatalytic oxidation of other small organic molecules.
Potential oscillation during the electrocatalytic oxidation of methanol can be modulated by the specific adsorption of Cl- on the platinum electrode, which suppresses the electrocatalytic oxidation of methanol, and makes the cross cycle in the cyclic voltammogram become smaller and finally disappear with the increase of Cl- concentration. The method is also applicable to the electrocatalytic oxidation of other small organic molecules.
2002, 13(3): 279-282
Abstract:
A novel class of desulfurization agent derived from hydrotalcite has been developed and its activity for Sox uptake have been investigated. The results showed that the Mg/Fe mixed oxide having high Sox uptake ability at a broad reaction temperature (e.g. 673K~973K). The Mg/Fe ratio of the mixed oxide strongly affect the desulfurization role of the material and it can be used repeatly without much loss of Sox uptake ability.
A novel class of desulfurization agent derived from hydrotalcite has been developed and its activity for Sox uptake have been investigated. The results showed that the Mg/Fe mixed oxide having high Sox uptake ability at a broad reaction temperature (e.g. 673K~973K). The Mg/Fe ratio of the mixed oxide strongly affect the desulfurization role of the material and it can be used repeatly without much loss of Sox uptake ability.
