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1997 Volume 8 Issue 3
1997, 8(3): 189-190
Abstract:
The reaction of phenylethyne with 2,4-pentanedione in the presence of manganese(Ⅲ) acetate and oxygen at room temprature gave 4-acetyl-5-benzoyl-3-methyl-1,2-dioxolan-3-ol, 2-acetyl-3-benzoloxirane and 3-acetyl-2-methyl-phenylfuran.
The reaction of phenylethyne with 2,4-pentanedione in the presence of manganese(Ⅲ) acetate and oxygen at room temprature gave 4-acetyl-5-benzoyl-3-methyl-1,2-dioxolan-3-ol, 2-acetyl-3-benzoloxirane and 3-acetyl-2-methyl-phenylfuran.
1997, 8(3): 191-192
Abstract:
Sodium alkyl thiosulfates(Bunte salts) can be readily reduced to the corresponding disulfides with TiCl4/Sm system in good to excellent yields under mild conditions.
Sodium alkyl thiosulfates(Bunte salts) can be readily reduced to the corresponding disulfides with TiCl4/Sm system in good to excellent yields under mild conditions.
1997, 8(3): 193-194
Abstract:
It is experimentally found that different reaction courses exist when nitrite ion reacts with nitrobenzenes with different electron withdrawing groups.When it is substituted with strong electron withdrawing groups.self-condensation in aprotic polar solvent occurs to give symmetrical disubstituted diphenyl ethers.However.when it is substituted with moderate electron withdrawing groups,no diphenyl ethers are obtained under the same conditions,instead,corresponding carboxylates are yielded.As a result,the applicability of this reaction is distinctly clarified.
It is experimentally found that different reaction courses exist when nitrite ion reacts with nitrobenzenes with different electron withdrawing groups.When it is substituted with strong electron withdrawing groups.self-condensation in aprotic polar solvent occurs to give symmetrical disubstituted diphenyl ethers.However.when it is substituted with moderate electron withdrawing groups,no diphenyl ethers are obtained under the same conditions,instead,corresponding carboxylates are yielded.As a result,the applicability of this reaction is distinctly clarified.
1997, 8(3): 195-198
Abstract:
Twelve new (3-benzyl-4-aroyl-1,2,4-triazole-5-yl)[5-(3,4,5-trimethoxyphenyl)-1,3,4-oxadiazole-2-yl] sulfides(2) have been synthesized from the nucieophilic displacements of 3-benzyl-4-aroyl-1,2,4-triazole-5-hydrosulfuryl anion on the 2-position of 2-methylsulfonyl-5-(3,4,5-trimethoxyphenyl)-1,3,4-oxadiazole(1).Compounds(2) were screened for their antibacterial activity against E.Coli at 0.01%.The results show that some compounds(2) have strong inhibiting effects.
Twelve new (3-benzyl-4-aroyl-1,2,4-triazole-5-yl)[5-(3,4,5-trimethoxyphenyl)-1,3,4-oxadiazole-2-yl] sulfides(2) have been synthesized from the nucieophilic displacements of 3-benzyl-4-aroyl-1,2,4-triazole-5-hydrosulfuryl anion on the 2-position of 2-methylsulfonyl-5-(3,4,5-trimethoxyphenyl)-1,3,4-oxadiazole(1).Compounds(2) were screened for their antibacterial activity against E.Coli at 0.01%.The results show that some compounds(2) have strong inhibiting effects.
1997, 8(3): 199-202
Abstract:
Uridine 2',3'-cyclic phosphite has been synthesized and the diastereomers were analysed by 2D NMR technique to assign the configuration.
Uridine 2',3'-cyclic phosphite has been synthesized and the diastereomers were analysed by 2D NMR technique to assign the configuration.
1997, 8(3): 203-204
Abstract:
An unexpected diene isomerization of the triene acid 3 in the Lewis acid catalyzed intramolecular Diels-Alder reaction was observed.
An unexpected diene isomerization of the triene acid 3 in the Lewis acid catalyzed intramolecular Diels-Alder reaction was observed.
1997, 8(3): 205-206
Abstract:
Przewaquinone A, a natural orthoquinone was synthesized through several steps,the analytic data of the synthetic target compound was identical with that of przewaquinone A.
Przewaquinone A, a natural orthoquinone was synthesized through several steps,the analytic data of the synthetic target compound was identical with that of przewaquinone A.
1997, 8(3): 207-208
Abstract:
Five new nitroxyl spin labeled podophyllotoxins (2-6) have been synthesized. Compounds 2 and 3 have been tested for their anticancer activity in vitro.The results showed that compound 3 is much more potent than the clinically used etoposide (VP-16) in its inhibition of P388 cells,while compound 2 is not active.
Five new nitroxyl spin labeled podophyllotoxins (2-6) have been synthesized. Compounds 2 and 3 have been tested for their anticancer activity in vitro.The results showed that compound 3 is much more potent than the clinically used etoposide (VP-16) in its inhibition of P388 cells,while compound 2 is not active.
1997, 8(3): 209-212
Abstract:
This paper deals with the synthesis of three new symmetrical bis (macrocylic) polyamines and their dinuclear copper (Ⅱ) complexes.All these compounds were identified by elemental analysis and spectral analysis (IR,1H and 13C NMR).
This paper deals with the synthesis of three new symmetrical bis (macrocylic) polyamines and their dinuclear copper (Ⅱ) complexes.All these compounds were identified by elemental analysis and spectral analysis (IR,1H and 13C NMR).
1997, 8(3): 213-214
Abstract:
5,11,17,23-Tetra-tertbutyl-25,27-dihydroxy-26,28-1',7',13'-trioxa-4',10'-dithiatridecene calix[4]arene (Calix[4]dithiacrown-5) was synthesized from tetra-tert-butyl-calix[4]arene via 1,3-lower rim functionallization with chloroethyltosylate,followed by ring-closing condensation with β,β'-dimercaptoethyl ether in the presence of sodium ethoxide as a base under nitrogen atmosphere.It was found that the calix[4]dithiacrown-5 can form a platinum complex and the complex can catalyze the hydrosilylation of olefins with triethoxysilane efficiently.
5,11,17,23-Tetra-tertbutyl-25,27-dihydroxy-26,28-1',7',13'-trioxa-4',10'-dithiatridecene calix[4]arene (Calix[4]dithiacrown-5) was synthesized from tetra-tert-butyl-calix[4]arene via 1,3-lower rim functionallization with chloroethyltosylate,followed by ring-closing condensation with β,β'-dimercaptoethyl ether in the presence of sodium ethoxide as a base under nitrogen atmosphere.It was found that the calix[4]dithiacrown-5 can form a platinum complex and the complex can catalyze the hydrosilylation of olefins with triethoxysilane efficiently.
1997, 8(3): 215-218
Abstract:
The methylated β-cyclodextrins derived optically active polymers are first synthesized through asymmetric polymerization of N-diphenylmethyl maleimide with lithium salt of heptakis (2,6-O-dimethyl) β-cyclodextrin (DM-β-CD) as an initiator.The resulting polymers show negative specific rotation which is opposite in sign to that of DM-β-CD.The asymmetric induction is further confirmed by circular dichroism.The structure is characterized by IR and NMR spectroscopies.
The methylated β-cyclodextrins derived optically active polymers are first synthesized through asymmetric polymerization of N-diphenylmethyl maleimide with lithium salt of heptakis (2,6-O-dimethyl) β-cyclodextrin (DM-β-CD) as an initiator.The resulting polymers show negative specific rotation which is opposite in sign to that of DM-β-CD.The asymmetric induction is further confirmed by circular dichroism.The structure is characterized by IR and NMR spectroscopies.
1997, 8(3): 219-220
Abstract:
Inclusion complexes of nitro-compounds using β-cyclodextrin and hydroxypropyl-β-cyclodextrin as host molecule have been studied by cyclic voltammetric method.The inclusion constants of the corresponding complexes have been determined.Strong inclusion complexation by hydroxypropyl-β-cyclodextrin has been verified.
Inclusion complexes of nitro-compounds using β-cyclodextrin and hydroxypropyl-β-cyclodextrin as host molecule have been studied by cyclic voltammetric method.The inclusion constants of the corresponding complexes have been determined.Strong inclusion complexation by hydroxypropyl-β-cyclodextrin has been verified.
1997, 8(3): 221-224
Abstract:
Bovine serum albumin (BSA) was labeled with 9,10-anthraquinone and the photochemical fluorimetric reactivity of the covalently conjugated 9,10-anthraquinone was remarkably improved.The mechanism for the enhancement in the photochemical reactivity of conjugated 9,10-anthraquinone with BSA was discussed.
Bovine serum albumin (BSA) was labeled with 9,10-anthraquinone and the photochemical fluorimetric reactivity of the covalently conjugated 9,10-anthraquinone was remarkably improved.The mechanism for the enhancement in the photochemical reactivity of conjugated 9,10-anthraquinone with BSA was discussed.
1997, 8(3): 225-228
Abstract:
Erigoster A (1a),a new compound with a novel basic skeleton,was isolated from Erigeron breviscapus.The structure elucidation and complete proton and carbon NMR assignments were achieved by the utilization of a combination of two-dimensional NMR techniques.
Erigoster A (1a),a new compound with a novel basic skeleton,was isolated from Erigeron breviscapus.The structure elucidation and complete proton and carbon NMR assignments were achieved by the utilization of a combination of two-dimensional NMR techniques.
1997, 8(3): 229-230
Abstract:
A new coumarin glucoside,daphkoreanin,has been isolated from the roots and stems of Daphne koreana.Its structure was established as 5-methoxy-7-hydroxy coumarin-8-O-β-D-glucoside by physico-chemical properties and 1HNMR spectral analysis.
A new coumarin glucoside,daphkoreanin,has been isolated from the roots and stems of Daphne koreana.Its structure was established as 5-methoxy-7-hydroxy coumarin-8-O-β-D-glucoside by physico-chemical properties and 1HNMR spectral analysis.
1997, 8(3): 231-232
Abstract:
A new taxoid,taxuchin B[1],has been isolated from twigs and needles of Taxus chinensis.It is the first chlorine-containing taxoid reported to date.
A new taxoid,taxuchin B[1],has been isolated from twigs and needles of Taxus chinensis.It is the first chlorine-containing taxoid reported to date.
1997, 8(3): 233-234
Abstract:
A novel bioactive Amionaceous acetogenin,donhexocin (1),has been isolated from the roots of Goniothalamus donnaiensis (Annonaceae).1 is a new acetogenin lacking THF rings but bearing six hydroxyls including two vic-diol systems in the aliphatic chain.Its structure and stereochemistry has been elucidated by spectoscopic analysis and derivatization.
A novel bioactive Amionaceous acetogenin,donhexocin (1),has been isolated from the roots of Goniothalamus donnaiensis (Annonaceae).1 is a new acetogenin lacking THF rings but bearing six hydroxyls including two vic-diol systems in the aliphatic chain.Its structure and stereochemistry has been elucidated by spectoscopic analysis and derivatization.
1997, 8(3): 235-236
Abstract:
24s-Stigmasta,4,25-diene,3β,6β-diol 1,a new sterol has been isolated from the algae Laurencia majuscula collected from the south China sea.Its structure was elucidated by spectroscopic methods.Compound 1 was cytotoxic against the P-388 cell line with an IC50 value of 1.2 μg/ml.
24s-Stigmasta,4,25-diene,3β,6β-diol 1,a new sterol has been isolated from the algae Laurencia majuscula collected from the south China sea.Its structure was elucidated by spectroscopic methods.Compound 1 was cytotoxic against the P-388 cell line with an IC50 value of 1.2 μg/ml.
1997, 8(3): 237-238
Abstract:
Isaindigotone 1 and 3-(2'-hydroxyphenyl)-4(3H)-quinazolinone 2 were isolated from the roots of Isatis indigotica.Compound 1 was elucidated as a new alkaloid.Compound 2 was discovered for the first time from a natural source.
Isaindigotone 1 and 3-(2'-hydroxyphenyl)-4(3H)-quinazolinone 2 were isolated from the roots of Isatis indigotica.Compound 1 was elucidated as a new alkaloid.Compound 2 was discovered for the first time from a natural source.
1997, 8(3): 239-242
Abstract:
A zinc phthalocyanine containing (17-crown-5) ether subunits has been synthesized.UV-visible absorption and fluorescence emission spectra and associated photophysical parameters have been determined.In addition to the fluorescence at 710 nm from S1.a strong upper excited state emission around 424 nm has been detected.X-ray structural analysis showed that the crown ether unit is conformationally deformed and oblate like that accounted for the unusual spectroscopic properties.
A zinc phthalocyanine containing (17-crown-5) ether subunits has been synthesized.UV-visible absorption and fluorescence emission spectra and associated photophysical parameters have been determined.In addition to the fluorescence at 710 nm from S1.a strong upper excited state emission around 424 nm has been detected.X-ray structural analysis showed that the crown ether unit is conformationally deformed and oblate like that accounted for the unusual spectroscopic properties.
1997, 8(3): 243-246
Abstract:
Recently biospecific affinity chromatography has been widely used for the separation and purification of various enzymes and nucleic acids.In this paper,a series of synthetic reactions of solid-liquid phase were carried out on silica surface,using a macroporous (30μm), microspherical silica (8μm) as the matrix and γ-aminopropyltriethoxysilane as the activating agent,the nicotinamide adenine dinucleotide (NAD) was bonded through its amino groups to the carboxylic groups of linked phospholipid which was bonded covalently on aminated support.The bonded stationary phase has high thermal stability,and could be used to separate of nucleotides with good resolution.
Recently biospecific affinity chromatography has been widely used for the separation and purification of various enzymes and nucleic acids.In this paper,a series of synthetic reactions of solid-liquid phase were carried out on silica surface,using a macroporous (30μm), microspherical silica (8μm) as the matrix and γ-aminopropyltriethoxysilane as the activating agent,the nicotinamide adenine dinucleotide (NAD) was bonded through its amino groups to the carboxylic groups of linked phospholipid which was bonded covalently on aminated support.The bonded stationary phase has high thermal stability,and could be used to separate of nucleotides with good resolution.
1997, 8(3): 247-250
Abstract:
A new ascorbic acid sensor constituted of carbon paste and Fe(Ⅲ)Y zeolite was studied.The characters of the sensor such as linear range、potential window、apparent Michaelis constant、response time、stability and accuracy were investigated.The experimental results indicate that the analytical performance of the sensor is satisfactory.
A new ascorbic acid sensor constituted of carbon paste and Fe(Ⅲ)Y zeolite was studied.The characters of the sensor such as linear range、potential window、apparent Michaelis constant、response time、stability and accuracy were investigated.The experimental results indicate that the analytical performance of the sensor is satisfactory.
1997, 8(3): 251-254
Abstract:
A PVC membrane electrode,using bis(tribenzyltin) oxide as the carrier,displayed selective response to hydrogen phosphate in the 5×10-6mol/L to 10-1mol/L activity range with a slope of -30.1mV/dec.in solutions of pH 7.2.The comparison of potential response characteristics between the binuclear and mononuclear organotin compounds has been made,showing that binuclear organometallic compounds may become a promising class of carriers for anions.
A PVC membrane electrode,using bis(tribenzyltin) oxide as the carrier,displayed selective response to hydrogen phosphate in the 5×10-6mol/L to 10-1mol/L activity range with a slope of -30.1mV/dec.in solutions of pH 7.2.The comparison of potential response characteristics between the binuclear and mononuclear organotin compounds has been made,showing that binuclear organometallic compounds may become a promising class of carriers for anions.
1997, 8(3): 255-258
Abstract:
A new C2-symmetric diamine/diphosphine Ruthenium (Ⅱ) complex,RuCl2P2N2H4.was used as an excellent catalyst to carry out the catalytic hydrogen transfer reduction of acetophenone.The conversion of acetophenone to 2-phenylethanol was up to 99% under the following reaction conditions: substrate: Ru: (CH3)2CHOK=200:1:12; reaction temperature of 65℃,reaction time of 2 h.normal pressure.A hydride transfer mechanism was also discussed.
A new C2-symmetric diamine/diphosphine Ruthenium (Ⅱ) complex,RuCl2P2N2H4.was used as an excellent catalyst to carry out the catalytic hydrogen transfer reduction of acetophenone.The conversion of acetophenone to 2-phenylethanol was up to 99% under the following reaction conditions: substrate: Ru: (CH3)2CHOK=200:1:12; reaction temperature of 65℃,reaction time of 2 h.normal pressure.A hydride transfer mechanism was also discussed.
1997, 8(3): 259-262
Abstract:
A new type of ammine palladium(Ⅱ) chloride was prepared by evaporating the solution of [Pd(NH3)]4Cl2 at room temperature.Its crystal structure was refined from single-crystal X-ray data:P42/nmc,a=10.5390(10)Å,c=16.905(3)Å,Z=2,and R=0.0357 for 731 structure factors and 52 variable parameters.The framework of the title compound is composed of three sorts of structural units: [Pd(NH3)4]2+, [Pd(NH3)3Cl]+,and Cl-,of which the first kind of least squares plane exhibits distortion in some degree.
A new type of ammine palladium(Ⅱ) chloride was prepared by evaporating the solution of [Pd(NH3)]4Cl2 at room temperature.Its crystal structure was refined from single-crystal X-ray data:P42/nmc,a=10.5390(10)Å,c=16.905(3)Å,Z=2,and R=0.0357 for 731 structure factors and 52 variable parameters.The framework of the title compound is composed of three sorts of structural units: [Pd(NH3)4]2+, [Pd(NH3)3Cl]+,and Cl-,of which the first kind of least squares plane exhibits distortion in some degree.
1997, 8(3): 263-266
Abstract:
PbS nanoparticles coated with 2,6-O-diallyl-β-CD were prepared successfully and characterized by transmission electron microscope (TEM),X-ray photoelectron spectrometer (XPS).The sample shows a very rapid induced absorption.
PbS nanoparticles coated with 2,6-O-diallyl-β-CD were prepared successfully and characterized by transmission electron microscope (TEM),X-ray photoelectron spectrometer (XPS).The sample shows a very rapid induced absorption.
