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1995 Volume 6 Issue 7
1995, 6(7): 549-552
Abstract:
5'-Amino adenosines were synthesized by substitution of 5'-O-(1-benzotriazolyl)-sulfonyl adenosine with various amines in very good yields.
5'-Amino adenosines were synthesized by substitution of 5'-O-(1-benzotriazolyl)-sulfonyl adenosine with various amines in very good yields.
1995, 6(7): 553-554
Abstract:
Nitroarenes were selectively reduced to primary amines by treatment with sodium borohydride bismuth chloride in the presence of nitrites.The selectivity was always excellent.
Nitroarenes were selectively reduced to primary amines by treatment with sodium borohydride bismuth chloride in the presence of nitrites.The selectivity was always excellent.
1995, 6(7): 555-556
Abstract:
In this paper, we report the chemical synthesis of oligonucleotide d-(CCGTACGG) using new HELP method.
In this paper, we report the chemical synthesis of oligonucleotide d-(CCGTACGG) using new HELP method.
1995, 6(7): 557-558
Abstract:
The reaction of enamine with ethyl diazoacetate catalyzed by N-α-(4-chlorophenyl)-isobutyl(salicylaldimino) copper complex gives cyclopropanation product with a yield of about 12%.
The reaction of enamine with ethyl diazoacetate catalyzed by N-α-(4-chlorophenyl)-isobutyl(salicylaldimino) copper complex gives cyclopropanation product with a yield of about 12%.
1995, 6(7): 559-560
Abstract:
A ten-step synthesis of 7-deoxy-1, 2, 10, 20-tetrahydrotaxamairin B(5), a key precursor for taxamairin A(1), B(2), has been achieved.A Friedel-Crafts annunation is the key step.
A ten-step synthesis of 7-deoxy-1, 2, 10, 20-tetrahydrotaxamairin B(5), a key precursor for taxamairin A(1), B(2), has been achieved.A Friedel-Crafts annunation is the key step.
1995, 6(7): 561-564
Abstract:
Some phosphorus reagents were applied to the Mannich-type reaction of carbamate and p-toluenesulfonamide so that some important intermediates for the synthesis of phosphonopeptides were obtained easily.The structures of products were confirmed by 1HNMR and elemental analyses.
Some phosphorus reagents were applied to the Mannich-type reaction of carbamate and p-toluenesulfonamide so that some important intermediates for the synthesis of phosphonopeptides were obtained easily.The structures of products were confirmed by 1HNMR and elemental analyses.
1995, 6(7): 565-568
Abstract:
By refluxing with cuprous halides in acetonitrile trialkyl phosphites can be directly converted into the corresponding dialkyl alkylphosphonate.The conversion of trialkyl phosphites with cuprous iodide is more favorable than with cuprous chloride;The activity of the alkyl group for the rearrangement is in the order of Me> Et> butyl.
By refluxing with cuprous halides in acetonitrile trialkyl phosphites can be directly converted into the corresponding dialkyl alkylphosphonate.The conversion of trialkyl phosphites with cuprous iodide is more favorable than with cuprous chloride;The activity of the alkyl group for the rearrangement is in the order of Me> Et> butyl.
1995, 6(7): 569-572
Abstract:
Fullerene derivatives C60NAr 2 were synthesized by the reaction of fullerene C60 with p-substituted phenyl azides in refluxing chlorobenzene.The structure of each product was elucidated on the basis of FD-MS、UV-Vis, IR, 1H NMR and 13C NMR as a closed aziridine at a 6/6-ring junction.
Fullerene derivatives C60NAr 2 were synthesized by the reaction of fullerene C60 with p-substituted phenyl azides in refluxing chlorobenzene.The structure of each product was elucidated on the basis of FD-MS、UV-Vis, IR, 1H NMR and 13C NMR as a closed aziridine at a 6/6-ring junction.
1995, 6(7): 573-576
Abstract:
Three 1-long hydrocarbon chain substituted pyrryl fulgides, (2, 4-dimethyl-1-hexadecyl-5-phenyl-3-pyrryl)-ethylidene(isopropylidene)succinic anhydride(1E), (2, 4-dimethyl-1-octadecyl-5-phenyl-3-pyrryl)-ethylidene(isopropylidene)succinic anhydride(2E)and(2-methyl-1-(p-octadecoxyphenyl)-5-phenyl-3-pyrryl)-ethylidene(isopropylidene)succinic anhydride(3E)were synthesized.Their photochromic behaviors were also investigated.Compound 3E was obtained in much higher yield(41.7%)than others with an improved procedure.
Three 1-long hydrocarbon chain substituted pyrryl fulgides, (2, 4-dimethyl-1-hexadecyl-5-phenyl-3-pyrryl)-ethylidene(isopropylidene)succinic anhydride(1E), (2, 4-dimethyl-1-octadecyl-5-phenyl-3-pyrryl)-ethylidene(isopropylidene)succinic anhydride(2E)and(2-methyl-1-(p-octadecoxyphenyl)-5-phenyl-3-pyrryl)-ethylidene(isopropylidene)succinic anhydride(3E)were synthesized.Their photochromic behaviors were also investigated.Compound 3E was obtained in much higher yield(41.7%)than others with an improved procedure.
1995, 6(7): 577-580
Abstract:
Reaction of oxyphosphorane (1) with thymidine (2) followed by hydrolysis under mild conditions afforded TMP, TpT and thymidine-3'-yl benzoin phosphates (3).The structures of 3 were determined by 31P, 1H, 13C NMR and mass spectral data, and 31P-1H COSY experiments.The possible formation mechanism of 3 was also discussed.
Reaction of oxyphosphorane (1) with thymidine (2) followed by hydrolysis under mild conditions afforded TMP, TpT and thymidine-3'-yl benzoin phosphates (3).The structures of 3 were determined by 31P, 1H, 13C NMR and mass spectral data, and 31P-1H COSY experiments.The possible formation mechanism of 3 was also discussed.
1995, 6(7): 581-582
Abstract:
This paper describes the structural elucidatioa of a new insecticidal neo-clerodane diterpeae Ajugamarin L2 from Ajugs nipponeasis.based on spectral data and X-ray diffraction analysis as 4, 18-epoxy-6α-hydroxy-19-tigloyloxy-neo-cierod-13(14)-en-15, 16-olide.
This paper describes the structural elucidatioa of a new insecticidal neo-clerodane diterpeae Ajugamarin L2 from Ajugs nipponeasis.based on spectral data and X-ray diffraction analysis as 4, 18-epoxy-6α-hydroxy-19-tigloyloxy-neo-cierod-13(14)-en-15, 16-olide.
1995, 6(7): 583-584
Abstract:
A new guaiane sesquiterpene was isolated from Ligularia Nelumbifolia.Its structure was elucidated by spectroscopic methods including 2D-NMR techniques and showed to be 4α, 9α, 10β-tri-acetoxy-1β, 5α-guaia-6-ene(1).
A new guaiane sesquiterpene was isolated from Ligularia Nelumbifolia.Its structure was elucidated by spectroscopic methods including 2D-NMR techniques and showed to be 4α, 9α, 10β-tri-acetoxy-1β, 5α-guaia-6-ene(1).
1995, 6(7): 585-586
Abstract:
Two new sesquiterpeuoids.named as tussilagonone Ⅰ(1)and neotussilagolactone Ⅰ(2), were isolated from the dry flower bud of Tussilago farfara L., Their structures were elucidated by the spectroscopic methods.In the test of platelet aggregation caused by platelet activating factor(PAF), compounds 1 and 2 were active.
Two new sesquiterpeuoids.named as tussilagonone Ⅰ(1)and neotussilagolactone Ⅰ(2), were isolated from the dry flower bud of Tussilago farfara L., Their structures were elucidated by the spectroscopic methods.In the test of platelet aggregation caused by platelet activating factor(PAF), compounds 1 and 2 were active.
1995, 6(7): 587-588
Abstract:
A new chrome glycoside, 5, 7-dihydroxychromone-3-O-L-rhamnopyranoside, named smiglanin, was isolated from the root of Smilax glabra collected in Lanxi, Zhejiang province.Its structure was elucidated by special data and chemical evidence.
A new chrome glycoside, 5, 7-dihydroxychromone-3-O-L-rhamnopyranoside, named smiglanin, was isolated from the root of Smilax glabra collected in Lanxi, Zhejiang province.Its structure was elucidated by special data and chemical evidence.
1995, 6(7): 589-592
Abstract:
This paper discussed the determination method of flavonoid compounds in Gingko biloba leaves with supercritical CO2 and HPLC, The method is simple and accurate.It can eliminate the toxicity of residual solvents in organic solvent extracts.The average recovery is 87.3%(n=4), relative standard deviation(RSD)is 5.4% and the method detection limit(MDL)is 28ppb.The flavonoid content determined was 1.4%(w/w)in Gingko biloba leaves.
This paper discussed the determination method of flavonoid compounds in Gingko biloba leaves with supercritical CO2 and HPLC, The method is simple and accurate.It can eliminate the toxicity of residual solvents in organic solvent extracts.The average recovery is 87.3%(n=4), relative standard deviation(RSD)is 5.4% and the method detection limit(MDL)is 28ppb.The flavonoid content determined was 1.4%(w/w)in Gingko biloba leaves.
1995, 6(7): 593-596
Abstract:
A new kinetic method based on detecting the intermediate products in successive reactions is described.The special bandshape kinetic curve is essential to establish the method.Epinephrine is determined selectively by this method in four catecholamine mixtures.
A new kinetic method based on detecting the intermediate products in successive reactions is described.The special bandshape kinetic curve is essential to establish the method.Epinephrine is determined selectively by this method in four catecholamine mixtures.
1995, 6(7): 597-600
Abstract:
The photochemical reaction of methylene blue(n-butyltriphenyl) borate, MBRBPh3 was examined.The ultrafast quenching rate and large negative value of △G indicated that the intra-ion pair ET plays an important role in photoreaction of MBRBPh3.The sequent boron-carbon bond cleavage of butyltriphenylboranyl radical intermediate was found by GC-MS and photo-CIDNP studies.
The photochemical reaction of methylene blue(n-butyltriphenyl) borate, MBRBPh3 was examined.The ultrafast quenching rate and large negative value of △G indicated that the intra-ion pair ET plays an important role in photoreaction of MBRBPh3.The sequent boron-carbon bond cleavage of butyltriphenylboranyl radical intermediate was found by GC-MS and photo-CIDNP studies.
1995, 6(7): 601-604
Abstract:
Chemical equilibrium calculation for predicting the pH values and buffering capacity of acidic natural surface waters was developed.Effects of various influence factors were investigated through theoretical analysis.Some valuable conclusions are obtained.
Chemical equilibrium calculation for predicting the pH values and buffering capacity of acidic natural surface waters was developed.Effects of various influence factors were investigated through theoretical analysis.Some valuable conclusions are obtained.
1995, 6(7): 605-608
Abstract:
Water-insoluble carboxyl-containing starch graft polymers were prepared.Residual metal ion concentrations in solutions treated with the insoluble starch graft polymers were measured in different pH.The mechanism of removing heavy-metals from aqueous solutions with the carboxylated starchs was described.
Water-insoluble carboxyl-containing starch graft polymers were prepared.Residual metal ion concentrations in solutions treated with the insoluble starch graft polymers were measured in different pH.The mechanism of removing heavy-metals from aqueous solutions with the carboxylated starchs was described.
1995, 6(7): 609-612
Abstract:
ZnAl hydrotalcites have been intercalated by THPOMs[BW11O39Z(H2O)n-(Z=Ni2+, Cu2+ and Al3+)] via both hydrothermal reaction and ion exchange reaction.The spectra of powder X-ray diffraction and IR show that the synthesized complexes pillared by THPOMs are layered compounds with gallery heights of 9.7~9.9Å, The anions entering the layer retain their Keggin structure.
ZnAl hydrotalcites have been intercalated by THPOMs[BW11O39Z(H2O)n-(Z=Ni2+, Cu2+ and Al3+)] via both hydrothermal reaction and ion exchange reaction.The spectra of powder X-ray diffraction and IR show that the synthesized complexes pillared by THPOMs are layered compounds with gallery heights of 9.7~9.9Å, The anions entering the layer retain their Keggin structure.
1995, 6(7): 613-616
Abstract:
The catalytic performances and surface properties of MgO prepared from different precursors were studied using catalytic test and pulse reaction techniques.It was indicated that the MgO prepared from Mg(OH)2·4MgCO3·6H2O pretreated with distilled water exhibited the highest activity for the oxidative coupling of methane.High lattice oxygen mobility and strong surface basicity may favor the OCM reaction.
The catalytic performances and surface properties of MgO prepared from different precursors were studied using catalytic test and pulse reaction techniques.It was indicated that the MgO prepared from Mg(OH)2·4MgCO3·6H2O pretreated with distilled water exhibited the highest activity for the oxidative coupling of methane.High lattice oxygen mobility and strong surface basicity may favor the OCM reaction.
1995, 6(7): 617-620
Abstract:
Lanthanocene complexes Cp'2LnCl(Cp'=ButCp, Ln=Yb, Er;Cp'=MeCp, Ln=Yb)or Cp'LnCl2(Cp'=ButCp, Ln=Yb, Nd;Cp'=MeCp, Ln=Yb) together with BuLi were first found to catalyze the selective dimerization of butanal to butyl butyrate in moderate yields under mild conditions.The yields were found to be influenced by the structure of lanthanocene complexes.
Lanthanocene complexes Cp'2LnCl(Cp'=ButCp, Ln=Yb, Er;Cp'=MeCp, Ln=Yb)or Cp'LnCl2(Cp'=ButCp, Ln=Yb, Nd;Cp'=MeCp, Ln=Yb) together with BuLi were first found to catalyze the selective dimerization of butanal to butyl butyrate in moderate yields under mild conditions.The yields were found to be influenced by the structure of lanthanocene complexes.
1995, 6(7): 621-624
Abstract:
29Si NMR is used to measure the concentration of the various functional groups in an acid catalyzed Si(OEt)4:EtOH:H2O sol-gel systems.The corresponding rate expressions for the reactions are shown in equations(1-3).The non-linear dynamics in the sol-gel process has been discussed.The molecular structure is changeable as the reactions proceed and the diffusion of clusters is spatially constrained.These factors iead to an anomalous kinetics, The overall rate coefficients have been got from numerical solution.
29Si NMR is used to measure the concentration of the various functional groups in an acid catalyzed Si(OEt)4:EtOH:H2O sol-gel systems.The corresponding rate expressions for the reactions are shown in equations(1-3).The non-linear dynamics in the sol-gel process has been discussed.The molecular structure is changeable as the reactions proceed and the diffusion of clusters is spatially constrained.These factors iead to an anomalous kinetics, The overall rate coefficients have been got from numerical solution.
1995, 6(7): 625-626
Abstract:
A technique has been developed for preparing stable polyurethane emulsion which provides thermosetting film without the use of emulsifying agents.The reaction of an isocyanate terminated prepolymer with a stoichiometric excess of diethylenetriamine in the presence of ketones yields the poly(urethane-amine).Then the free amino group is generated when the polymer is treated with epichlorohydrin and the reaction occurs between them, and a stable self-emulsifiable thermosetting urethane emulsion can be obtained.This paper also presents the effect of the curing temperature and time on the typical mechanical properties of the films from this urethane emulsion.
A technique has been developed for preparing stable polyurethane emulsion which provides thermosetting film without the use of emulsifying agents.The reaction of an isocyanate terminated prepolymer with a stoichiometric excess of diethylenetriamine in the presence of ketones yields the poly(urethane-amine).Then the free amino group is generated when the polymer is treated with epichlorohydrin and the reaction occurs between them, and a stable self-emulsifiable thermosetting urethane emulsion can be obtained.This paper also presents the effect of the curing temperature and time on the typical mechanical properties of the films from this urethane emulsion.
1995, 6(7): 627-630
Abstract:
For the first time, LB films containing Eu(TTA)3 Phen are obtained by using composite subphase.Eu(TTA)3 Phen itself is difficult to be transferred onto solid substrate, mixed or alternate LB films are prepared.Hydrogen bonds form between Eu(TTA)3 Phen and AA or TPP(-COOH).TOPO and SB have a fluorescence enhancement effect on Eu(TTA)3 Phen.TPP(-COOH)and Fc have a fluorescence quenching effect on it.
For the first time, LB films containing Eu(TTA)3 Phen are obtained by using composite subphase.Eu(TTA)3 Phen itself is difficult to be transferred onto solid substrate, mixed or alternate LB films are prepared.Hydrogen bonds form between Eu(TTA)3 Phen and AA or TPP(-COOH).TOPO and SB have a fluorescence enhancement effect on Eu(TTA)3 Phen.TPP(-COOH)and Fc have a fluorescence quenching effect on it.
1995, 6(7): 631-632
Abstract:
The structural parameters of the aggregated state under various heat treatment for PA-1010 samples were computed by means of the desmearing intensity from SAXS, and by using the concept of the distance distribution function and 1D EDCF method.The results revealed that the maximum values of Q, I(O), Pmax(Z), dtr, Rg and Wc, x were obtained nearby T=175℃ for PA-1010 samples with various annealing treatment.The higher degree of the crystallinity, the greater values of all the structural parameters of the aggregated state for PA-1010 samples were.
The structural parameters of the aggregated state under various heat treatment for PA-1010 samples were computed by means of the desmearing intensity from SAXS, and by using the concept of the distance distribution function and 1D EDCF method.The results revealed that the maximum values of Q, I(O), Pmax(Z), dtr, Rg and Wc, x were obtained nearby T=175℃ for PA-1010 samples with various annealing treatment.The higher degree of the crystallinity, the greater values of all the structural parameters of the aggregated state for PA-1010 samples were.
1995, 6(7): 633-636
Abstract:
Energy band calculations of tetrathiafulvalene-metal bisdithiolenes(C6S8M)∞(M=Ni, Pt)with the extended Hückel molecular orbital(EHMO)method show that the multiple overlaps among frontier molecular orbitals(FMO)and the small band gap account for their conducting properties.Their estimated conductivities are in good agreement with experimental data.FMO are mainly composed of ligand orbitals.Differences of the band structures between polymers and layered salts with the same building block are revealed.
Energy band calculations of tetrathiafulvalene-metal bisdithiolenes(C6S8M)∞(M=Ni, Pt)with the extended Hückel molecular orbital(EHMO)method show that the multiple overlaps among frontier molecular orbitals(FMO)and the small band gap account for their conducting properties.Their estimated conductivities are in good agreement with experimental data.FMO are mainly composed of ligand orbitals.Differences of the band structures between polymers and layered salts with the same building block are revealed.
1995, 6(7): 637-640
Abstract:
The thermal decompositions of the complex of Cd(Ⅱ)with o-vanillin thiosemicarbazone(complex 1)and the mixed ligand complex of iron(Ⅲ)with 2-[(o-hydroxybenzylidene)amino]phenol and pyridine(complex 2)and their non-isothermal kinetics have been studied by TG and DTG techniques.The non-isothermal kinetic data were analyzed and the kinetic parameters for the first and second steps of the thermal decompositions were evaluated by two different methods——differential and integral methods.Their kinetic equations were obtained.
The thermal decompositions of the complex of Cd(Ⅱ)with o-vanillin thiosemicarbazone(complex 1)and the mixed ligand complex of iron(Ⅲ)with 2-[(o-hydroxybenzylidene)amino]phenol and pyridine(complex 2)and their non-isothermal kinetics have been studied by TG and DTG techniques.The non-isothermal kinetic data were analyzed and the kinetic parameters for the first and second steps of the thermal decompositions were evaluated by two different methods——differential and integral methods.Their kinetic equations were obtained.
1995, 6(7): 641-644
Abstract:
Four new binuclear copper(Ⅱ)complexes[Cu2(L)(μ-X)]have been synthesized and characterized, where X=C6H5COO(1), C2H5COO(2), pyrazolate(C3H3N2)(3)and 1, 3-N3(4).The ligand H3L is a 2:1 Schiff base derived from 2-hydroxy-1-naphthaldehyde and 1, 3-diamino-2-propanol.The variable temperature magnetic analyses show that complexes(1), (2)and(3)are paramagnetic with 2J=-158~-188 cm-1, and complex(4)is diamagnetic with|2J|>1000 cm-1.
Four new binuclear copper(Ⅱ)complexes[Cu2(L)(μ-X)]have been synthesized and characterized, where X=C6H5COO(1), C2H5COO(2), pyrazolate(C3H3N2)(3)and 1, 3-N3(4).The ligand H3L is a 2:1 Schiff base derived from 2-hydroxy-1-naphthaldehyde and 1, 3-diamino-2-propanol.The variable temperature magnetic analyses show that complexes(1), (2)and(3)are paramagnetic with 2J=-158~-188 cm-1, and complex(4)is diamagnetic with|2J|>1000 cm-1.
