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1997 Volume 8 Issue 6
1997, 8(6): 465-466
Abstract:
The reaction of benzimidazole methoidide salt with bis-Grignard reagent is reported,and a new method for the preparation of dialdehyde is provided.
The reaction of benzimidazole methoidide salt with bis-Grignard reagent is reported,and a new method for the preparation of dialdehyde is provided.
1997, 8(6): 467-470
Abstract:
In this paper the reaction of vinyl triazole denvatives with hydroxylamine hydrochloride under the action of sodium carbonate was studied.The result indicated that cyclization took place and new heterocyclic compounds of 1,2-oxazocyclopentanes were obtained.
In this paper the reaction of vinyl triazole denvatives with hydroxylamine hydrochloride under the action of sodium carbonate was studied.The result indicated that cyclization took place and new heterocyclic compounds of 1,2-oxazocyclopentanes were obtained.
1997, 8(6): 471-472
Abstract:
TiCl4/Zn system reduces arylsulfonyl chlorides and sodium alkyl thiosulfates to corresponding disulfides in moderate to good yields.
TiCl4/Zn system reduces arylsulfonyl chlorides and sodium alkyl thiosulfates to corresponding disulfides in moderate to good yields.
1997, 8(6): 473-474
Abstract:
Using N-bromosuccinimide and pyridine as the oxidation system to dehydrogenate aryl substituted semicarbazide to form azo compounds is described for the first time in this paper.Nine azo compounds have been prepared in excellent yield under mild condition.This method only needs simple instrument and short reaction time.
Using N-bromosuccinimide and pyridine as the oxidation system to dehydrogenate aryl substituted semicarbazide to form azo compounds is described for the first time in this paper.Nine azo compounds have been prepared in excellent yield under mild condition.This method only needs simple instrument and short reaction time.
1997, 8(6): 475-476
Abstract:
Three cyclodextrin dimers bridged at C-6 by the shortest tether-a sulfur atom are synthesized by reacting cyclodextrin tosylates with Na2S and their binding properties are evaluated.
Three cyclodextrin dimers bridged at C-6 by the shortest tether-a sulfur atom are synthesized by reacting cyclodextrin tosylates with Na2S and their binding properties are evaluated.
1997, 8(6): 477-478
Abstract:
By ketal formation with chiral glycols like methyl or ethyl ester of tartaric acid,hydrogenation of ketals from the corresponding α,β-unsaturated 15-membered cyclic ketone produces (R)-muscone in good chemical and optical yield in the presence of chiral catalysts.
By ketal formation with chiral glycols like methyl or ethyl ester of tartaric acid,hydrogenation of ketals from the corresponding α,β-unsaturated 15-membered cyclic ketone produces (R)-muscone in good chemical and optical yield in the presence of chiral catalysts.
1997, 8(6): 479-482
Abstract:
By the Grignard reaction of 1,1-di-deutero-1-bromobutane with phthalaldehydic acid 1',1'-di-deutero-3-n-butyl phthalide was obtained.which underwent a rearrangement reaction using AlCl3 as catalyst in CS2 to give 1-methyl-5-carboxy-3,4-di-deutero-tetrahydronaphthalene.The mechanism was proposed to be a series of consecutive 1,2-hydride transfers rather than a direct 1,4-hydride transfer.
By the Grignard reaction of 1,1-di-deutero-1-bromobutane with phthalaldehydic acid 1',1'-di-deutero-3-n-butyl phthalide was obtained.which underwent a rearrangement reaction using AlCl3 as catalyst in CS2 to give 1-methyl-5-carboxy-3,4-di-deutero-tetrahydronaphthalene.The mechanism was proposed to be a series of consecutive 1,2-hydride transfers rather than a direct 1,4-hydride transfer.
1997, 8(6): 483-486
Abstract:
A novel type of estrogen-based receptor has been synthesized.These receptor compounds 3a-d have been characterized by mass spectra,1H NMR spectra,IR spectra and elemental analyses.
A novel type of estrogen-based receptor has been synthesized.These receptor compounds 3a-d have been characterized by mass spectra,1H NMR spectra,IR spectra and elemental analyses.
1997, 8(6): 487-490
Abstract:
Dendrimers have attracted attention in abroad area of chemistry.In this paper,octopus polyestrones were easily synthesized in a novel convergent strategy.
Dendrimers have attracted attention in abroad area of chemistry.In this paper,octopus polyestrones were easily synthesized in a novel convergent strategy.
1997, 8(6): 491-492
Abstract:
1α-and 1β-methyl agarofuran 1 and 2 were stereoselectively synthesized,the key intermediates being synthesized through stereoselective Robinson annulation.The conjugated double bond was reduced in an improved way.Alkylation of imine 7 with enone 8,9,10 was performed.
1α-and 1β-methyl agarofuran 1 and 2 were stereoselectively synthesized,the key intermediates being synthesized through stereoselective Robinson annulation.The conjugated double bond was reduced in an improved way.Alkylation of imine 7 with enone 8,9,10 was performed.
1997, 8(6): 493-496
Abstract:
Crinasiadine 1 has been easily synthesized by palladium acetate catalyzed cyclization of N-(o-bromophenyl)-3,4-methylenedioxybenzamide.The synthesis of trisphearidine 8 with a practical type of palladium chloride catalyzed cyclization as the key step is reported.
Crinasiadine 1 has been easily synthesized by palladium acetate catalyzed cyclization of N-(o-bromophenyl)-3,4-methylenedioxybenzamide.The synthesis of trisphearidine 8 with a practical type of palladium chloride catalyzed cyclization as the key step is reported.
1997, 8(6): 497-498
Abstract:
A novel type of fluorine-containing surfactants 5 was synthesized using aleuritic acid as a starting material in six steps with an overall yield of 9%.
A novel type of fluorine-containing surfactants 5 was synthesized using aleuritic acid as a starting material in six steps with an overall yield of 9%.
1997, 8(6): 499-502
Abstract:
Five new zwitterionic surfactants with long chain alkyl betaine structure incorporated with hydroxylpropyl group have been synthesized.Their structures were identified by elemental analysis,IR,1HNMR,and 13CNMR.Surface tension experiments showed that these surfactants have higher surface activity than those without hydroxypropyl group.The values of CMC and γCMC of these surfactants have been determined.
Five new zwitterionic surfactants with long chain alkyl betaine structure incorporated with hydroxylpropyl group have been synthesized.Their structures were identified by elemental analysis,IR,1HNMR,and 13CNMR.Surface tension experiments showed that these surfactants have higher surface activity than those without hydroxypropyl group.The values of CMC and γCMC of these surfactants have been determined.
1997, 8(6): 503-504
Abstract:
In this paper Comparative Molecular Field Analysis (CoMFA) method was applied to study the three-dimensional quantitative structure activity relationship (3D-QSAR) on a set of new herbicidal sulfonylureas.We optimized molecular structures to improve their activities.
In this paper Comparative Molecular Field Analysis (CoMFA) method was applied to study the three-dimensional quantitative structure activity relationship (3D-QSAR) on a set of new herbicidal sulfonylureas.We optimized molecular structures to improve their activities.
1997, 8(6): 505-508
Abstract:
One of the crucial parameters determining the electron transfer rate,Franck-Condon factor,was evaluated quantitatively for electron exchange reactions involving hexaquo-metal ions.Adopting appropriate spectroscopic and photoemission data,reasonable results were obtained and compared in terms of classical and quantum-mechanical theory.Investigation shows that for such reactions occurred at room temperature,nuclear tunneling effects increase the absolute rates by several times,which are not dramatic but still should be considered for complementary purpose.
One of the crucial parameters determining the electron transfer rate,Franck-Condon factor,was evaluated quantitatively for electron exchange reactions involving hexaquo-metal ions.Adopting appropriate spectroscopic and photoemission data,reasonable results were obtained and compared in terms of classical and quantum-mechanical theory.Investigation shows that for such reactions occurred at room temperature,nuclear tunneling effects increase the absolute rates by several times,which are not dramatic but still should be considered for complementary purpose.
1997, 8(6): 509-510
Abstract:
A new stilbene diglucoside,gnetifolin K.was isolated from the lianas of Gnetum parvifolium.Its structure was established as isorhapotigenin-3,4'-di-O-β-D-glucoside on the basis of spectral and chemical evidence.
A new stilbene diglucoside,gnetifolin K.was isolated from the lianas of Gnetum parvifolium.Its structure was established as isorhapotigenin-3,4'-di-O-β-D-glucoside on the basis of spectral and chemical evidence.
1997, 8(6): 511-514
Abstract:
Four new steroidal alkaloids,named sarcovagine A-D,were isolated from the roots of Sarcococca vagans.Their structures were determined as 20α-dimemylamino-2β,4β-dihydroxy-3β-tigloylamino-5α-pregnane (sarcovagine A,1),20α-dimethylamino-2α-hydroxy-4β-acetoxy-3β-tigloylamino-5α-pregnane (sarcovagine B,2),20α-dimethylamino-4β-acetoxy-3β-tigloylamino-5α-pregnane (sarcovagine C,3),20α-dimemylamino-3-tigloylamino-5α-pregn-2(3)-en-4-one (sarcovagine D,4),respectively.
Four new steroidal alkaloids,named sarcovagine A-D,were isolated from the roots of Sarcococca vagans.Their structures were determined as 20α-dimemylamino-2β,4β-dihydroxy-3β-tigloylamino-5α-pregnane (sarcovagine A,1),20α-dimethylamino-2α-hydroxy-4β-acetoxy-3β-tigloylamino-5α-pregnane (sarcovagine B,2),20α-dimethylamino-4β-acetoxy-3β-tigloylamino-5α-pregnane (sarcovagine C,3),20α-dimemylamino-3-tigloylamino-5α-pregn-2(3)-en-4-one (sarcovagine D,4),respectively.
1997, 8(6): 515-518
Abstract:
The metabolism of 7-(4-Chlorbenzyl)-7,8,13,13a-tetrahydroberberine chloride (CTHB),a potential anti-arrhythmia and anti-ischemia drug,was studied in rat bile.A metabolite and unchanged CTHB were found in the bile.Characterization and structural elucidation of the metabolite was achieved by LC/MS and LC/NMR.
The metabolism of 7-(4-Chlorbenzyl)-7,8,13,13a-tetrahydroberberine chloride (CTHB),a potential anti-arrhythmia and anti-ischemia drug,was studied in rat bile.A metabolite and unchanged CTHB were found in the bile.Characterization and structural elucidation of the metabolite was achieved by LC/MS and LC/NMR.
1997, 8(6): 519-522
Abstract:
Silica gel bonded stationary phases containing monoaza crown ether was synthesized via a series of solid-liquid phase reactions.The bonded molecular structure was characterized by chemical and instrumental analyses.The bonded stationary phase was provided with complexing ability with copper ion as well as hydrophobic property.The chromatographic retention behaviours of some substituted polar phenol derivatives,organic acids and bases on the bonded stationary phase were studied using methanol and/or aqueous solution of dibasic potassium phosphate buffer as mobile phase.When copper ion was added to the mobile phase at pH 5.4.the retention of substituted phenols became strong.
Silica gel bonded stationary phases containing monoaza crown ether was synthesized via a series of solid-liquid phase reactions.The bonded molecular structure was characterized by chemical and instrumental analyses.The bonded stationary phase was provided with complexing ability with copper ion as well as hydrophobic property.The chromatographic retention behaviours of some substituted polar phenol derivatives,organic acids and bases on the bonded stationary phase were studied using methanol and/or aqueous solution of dibasic potassium phosphate buffer as mobile phase.When copper ion was added to the mobile phase at pH 5.4.the retention of substituted phenols became strong.
1997, 8(6): 523-526
Abstract:
Prior to formation of the micelles of cationic surfactant (CSF),bromopyrogallol red (BPR) could exist in the forms of both monomer and oligomer.After that,however,only BPR monomer existed.Nonionic surfactant OP-10 favoured the oligomerization of BPR monomer.The mixed micellar media prepared by mixing CSF and OP-10 in an appropriate ratio could be used for the sensitive and selective determination of Mo in Mo/W binary mixtures.
Prior to formation of the micelles of cationic surfactant (CSF),bromopyrogallol red (BPR) could exist in the forms of both monomer and oligomer.After that,however,only BPR monomer existed.Nonionic surfactant OP-10 favoured the oligomerization of BPR monomer.The mixed micellar media prepared by mixing CSF and OP-10 in an appropriate ratio could be used for the sensitive and selective determination of Mo in Mo/W binary mixtures.
1997, 8(6): 527-528
Abstract:
A new method of differential thermal analysis and instrument were developed.The solution and pure solvent were placed in a cooling bath whose temperature was decreased by a semiconductor chip.Three detectors were used to sense the temperature (Ts,Tr and Tw) of solution (S),pure solvent (R) and cooling bath (W).When (Tr-Ts)-(Ts-Tw) presented maximum,(Tr-Ts) was the freezing point depression of the solution which was proportional to the concentration of solution.An instrument for the method was designed.
A new method of differential thermal analysis and instrument were developed.The solution and pure solvent were placed in a cooling bath whose temperature was decreased by a semiconductor chip.Three detectors were used to sense the temperature (Ts,Tr and Tw) of solution (S),pure solvent (R) and cooling bath (W).When (Tr-Ts)-(Ts-Tw) presented maximum,(Tr-Ts) was the freezing point depression of the solution which was proportional to the concentration of solution.An instrument for the method was designed.
1997, 8(6): 529-532
Abstract:
Adsorptive enhancements of several water-soluble polymers on copper(Ⅱ) were studied by adsorptive stripping voltammetry with a hanging mercury drop electrode.Increases in peak current of Cu(Ⅱ) were observed in alkaline carbonate media.The enhancing power of poly(vinyl alcohol),starch and polyallylamine is 15,4.1,and 2.5 times,respectively.
Adsorptive enhancements of several water-soluble polymers on copper(Ⅱ) were studied by adsorptive stripping voltammetry with a hanging mercury drop electrode.Increases in peak current of Cu(Ⅱ) were observed in alkaline carbonate media.The enhancing power of poly(vinyl alcohol),starch and polyallylamine is 15,4.1,and 2.5 times,respectively.
1997, 8(6): 533-534
Abstract:
In this letter,we report EQCM studies on the electrochemistry of poly(aminothiophenol) monolayer on Au in aqueous solutions.Results show that the monolayer polymer investigated exhibits only a one-step proton-involving redox process without doping and undoping behaviors similar to polyaniline.
In this letter,we report EQCM studies on the electrochemistry of poly(aminothiophenol) monolayer on Au in aqueous solutions.Results show that the monolayer polymer investigated exhibits only a one-step proton-involving redox process without doping and undoping behaviors similar to polyaniline.
1997, 8(6): 535-538
Abstract:
One kind of dual layer function separated architecture photoreceptors was prepared.As compared with that of single layered photoreceptor made of the same photogenerator material,their absorption spectra and electrophotographic properties were investigated systematically.The experimental results indicate that phthalocyanine compounds are appropriate photogenerators.The existence of CTL in the dual layered photoreceptor efficiently accelerated photodecay process and bring about a lower Vr value,and higher light sensitivity than that of single layered photoreceptor.These are attributed to carrier injection from CGL to CTL.The process might be interpreted as assistance sensitization effect based on carrier injection.It might play an important role in promoting the performance of dual layered photoreceptor.
One kind of dual layer function separated architecture photoreceptors was prepared.As compared with that of single layered photoreceptor made of the same photogenerator material,their absorption spectra and electrophotographic properties were investigated systematically.The experimental results indicate that phthalocyanine compounds are appropriate photogenerators.The existence of CTL in the dual layered photoreceptor efficiently accelerated photodecay process and bring about a lower Vr value,and higher light sensitivity than that of single layered photoreceptor.These are attributed to carrier injection from CGL to CTL.The process might be interpreted as assistance sensitization effect based on carrier injection.It might play an important role in promoting the performance of dual layered photoreceptor.
1997, 8(6): 539-542
Abstract:
Unilamellar vesicles from the mixtures of 1:1 sodium 10-undecenoate and trimethyl[2-(10-undecenoyloxy) ethyl] ammonium iodide in the mixed solvents of ethanol and heptane can be formed spontaneously or by sonication.They can exist in the variation of concentrations and volume ratios of ethanol to heptane,which indicates to some extent the high capability of vesicle formation in such mixed systems.
Unilamellar vesicles from the mixtures of 1:1 sodium 10-undecenoate and trimethyl[2-(10-undecenoyloxy) ethyl] ammonium iodide in the mixed solvents of ethanol and heptane can be formed spontaneously or by sonication.They can exist in the variation of concentrations and volume ratios of ethanol to heptane,which indicates to some extent the high capability of vesicle formation in such mixed systems.
1997, 8(6): 543-546
Abstract:
Excimer formation of pyrene and benzyl 4-(1-pyrenyl) butanoate was used to study the microviscosity of polystyrene/toluene solutions over the entire concentration range.Two critical concentrations (CPS~0.32,0.82g/ml) have been observed from the log-log plot of IE/IM vs CPS.The results are explained in terms of the onset of cohesional interaction and the glass transition of the polymer chains,respectively.
Excimer formation of pyrene and benzyl 4-(1-pyrenyl) butanoate was used to study the microviscosity of polystyrene/toluene solutions over the entire concentration range.Two critical concentrations (CPS~0.32,0.82g/ml) have been observed from the log-log plot of IE/IM vs CPS.The results are explained in terms of the onset of cohesional interaction and the glass transition of the polymer chains,respectively.
1997, 8(6): 547-550
Abstract:
It was found that the oxovanadium (V) complex of triethanolamine (TEA) exhibits catalytic activity to the oxidative cleavage of catechols.On the other hand,the vanadyl nitrilotriacetic acid (NTA) complex is inactive.but leads to the formation of stable ternary complex.The main products of the catalytic oxidative cleavage of 3.5-di-tert-butylcatechol were separated and characterized.Based on the results,a reaction mechanism was discussed.
It was found that the oxovanadium (V) complex of triethanolamine (TEA) exhibits catalytic activity to the oxidative cleavage of catechols.On the other hand,the vanadyl nitrilotriacetic acid (NTA) complex is inactive.but leads to the formation of stable ternary complex.The main products of the catalytic oxidative cleavage of 3.5-di-tert-butylcatechol were separated and characterized.Based on the results,a reaction mechanism was discussed.
1997, 8(6): 551-552
Abstract:
The binding of Co(phen)2dppz3+ to calf thymus DNA was investigated using absorption spectroscopy,viscosity and electrophoresis measurements,where dppz is dipyrido[3,2-a:2'3'-c] phenazine.The compound shows absorption hypochromicity and the specific viscosity increased upon binding to calf thymus DNA.The complex is also shown to be more efficient photosensitisers for single strand breaks in plasmid DNA.
The binding of Co(phen)2dppz3+ to calf thymus DNA was investigated using absorption spectroscopy,viscosity and electrophoresis measurements,where dppz is dipyrido[3,2-a:2'3'-c] phenazine.The compound shows absorption hypochromicity and the specific viscosity increased upon binding to calf thymus DNA.The complex is also shown to be more efficient photosensitisers for single strand breaks in plasmid DNA.
1997, 8(6): 553-554
Abstract:
The attractive and important complexes,manganese porphyrin aromatic thiolates,are prepared directly by the reaction of chloro(5,10,15,20-tetraphenylporphyrinato) manganese Mn(TPP)Cl with PhSNa and (p-NO2)PhSNa under extremely simple and mild reaction conditions.
The attractive and important complexes,manganese porphyrin aromatic thiolates,are prepared directly by the reaction of chloro(5,10,15,20-tetraphenylporphyrinato) manganese Mn(TPP)Cl with PhSNa and (p-NO2)PhSNa under extremely simple and mild reaction conditions.
1997, 8(6): 555-556
Abstract:
Two μ-isophthalato oxovanadium (Ⅱ) binuclear complexes,[(VO)2-(IPHTA)(phen)2]SO4 (1) and [(VO)2(IPHTA)(NO2-phen)2]SO4 (2) were synthesized and characterized.The magnetism of complex (1) was studied.
Two μ-isophthalato oxovanadium (Ⅱ) binuclear complexes,[(VO)2-(IPHTA)(phen)2]SO4 (1) and [(VO)2(IPHTA)(NO2-phen)2]SO4 (2) were synthesized and characterized.The magnetism of complex (1) was studied.
1997, 8(6): 557-558
Abstract:
A new Schiff base (LK) obtained from 2,4,-dihydroxybenzaldehyde and glycyl-DL-phenylalanine reacted with Cu(Ⅱ),Zn(Ⅱ),Ni(Ⅱ) and Co(Ⅱ) to yield new complexes.The complexes were characterized by elemental analyses,molar conductance,1H NMR,DTA,TG,BR and UV spectroscopy.In these complexes the ligand is coordinated to the metal through its phenolic oxygen,carboxyl oxygen,imino nitrogen and amide nitrogen.All complexes are non-electrolytes and four-coordinated with 1:1 (metal:ligand) stoichiometry.The probable structure of the complexes is suggested.
A new Schiff base (LK) obtained from 2,4,-dihydroxybenzaldehyde and glycyl-DL-phenylalanine reacted with Cu(Ⅱ),Zn(Ⅱ),Ni(Ⅱ) and Co(Ⅱ) to yield new complexes.The complexes were characterized by elemental analyses,molar conductance,1H NMR,DTA,TG,BR and UV spectroscopy.In these complexes the ligand is coordinated to the metal through its phenolic oxygen,carboxyl oxygen,imino nitrogen and amide nitrogen.All complexes are non-electrolytes and four-coordinated with 1:1 (metal:ligand) stoichiometry.The probable structure of the complexes is suggested.
