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1998 Volume 9 Issue 3
1998, 9(3): 231-232
Abstract:
α, α'-Dicinnamoyl ketene cyclic S, S-acetals 4 were reacted with ethylenediamine to afford α, α'-dicinnamoyl ketene cyclic N, N-acetals 5. This process provides a new method for the synthesis of 5 in high yield under mild conditions.
α, α'-Dicinnamoyl ketene cyclic S, S-acetals 4 were reacted with ethylenediamine to afford α, α'-dicinnamoyl ketene cyclic N, N-acetals 5. This process provides a new method for the synthesis of 5 in high yield under mild conditions.
1998, 9(3): 233-234
Abstract:
Aluminum chloride induced Diels-Alder reactions of 3-carboethoxy-and 3-carbonitrile-2-cyclohexen-1-one with cyclopentadiene, isoprene and (E)-piperylene were described. The stereochemistry of the adducts were confirmed by 2D-NMR spectroscopy and isomerization reactions.
Aluminum chloride induced Diels-Alder reactions of 3-carboethoxy-and 3-carbonitrile-2-cyclohexen-1-one with cyclopentadiene, isoprene and (E)-piperylene were described. The stereochemistry of the adducts were confirmed by 2D-NMR spectroscopy and isomerization reactions.
1998, 9(3): 235-236
Abstract:
The preparations and intramolecular cyclizations of amides 5, (N-methyl-N-(2-trans-2-phenylethenyl)-3-phenyl-2, 3-cis-oxiranecarboxamide) and 8, (N-methyl-N-(2-cis-2-phenylethenyl)-3-pheny 1-2, 3-cis-oxiranecarboxamide) were reported.
The preparations and intramolecular cyclizations of amides 5, (N-methyl-N-(2-trans-2-phenylethenyl)-3-phenyl-2, 3-cis-oxiranecarboxamide) and 8, (N-methyl-N-(2-cis-2-phenylethenyl)-3-pheny 1-2, 3-cis-oxiranecarboxamide) were reported.
1998, 9(3): 237-240
Abstract:
U. V. irradiation of N-methylphenothiazine 1 in carbon tetrachloride produced 3-(phenothiazin-N-yl-carbonyl)-N-methylphenothiazine 2 together with the radical cation salt 1+ CCl4- and methyl chloride, presumably via a photo induced electron transfer mechanism.
U. V. irradiation of N-methylphenothiazine 1 in carbon tetrachloride produced 3-(phenothiazin-N-yl-carbonyl)-N-methylphenothiazine 2 together with the radical cation salt 1+ CCl4- and methyl chloride, presumably via a photo induced electron transfer mechanism.
1998, 9(3): 241-244
Abstract:
An easy preparation of tetrahydropyranyl (THP) ethers of alcohols and phenols with 3, 4-dihydro-2H-pyran (DHP) in refluxing dichloromethane has been carried out in good to excellent yields under catalysis of anhydrous ferrous sulfate.
An easy preparation of tetrahydropyranyl (THP) ethers of alcohols and phenols with 3, 4-dihydro-2H-pyran (DHP) in refluxing dichloromethane has been carried out in good to excellent yields under catalysis of anhydrous ferrous sulfate.
1998, 9(3): 245-248
Abstract:
A novel Schiff base, N, N-bis[2-(2-iminoantipyrinephenoxy)ethyl]-p-toluenesulfonamide (BIAET), was synthesized and characterized, and a carbon paste electrode modified with BIAET was prepared and employed for quantitation of lead. The linear range, precision, limit of detection and interference have been investigated.
A novel Schiff base, N, N-bis[2-(2-iminoantipyrinephenoxy)ethyl]-p-toluenesulfonamide (BIAET), was synthesized and characterized, and a carbon paste electrode modified with BIAET was prepared and employed for quantitation of lead. The linear range, precision, limit of detection and interference have been investigated.
1998, 9(3): 249-250
Abstract:
The total synthesis of (±)-6-oxa-13β-ethyl-3-methoxy-8α-gona-1.3.5(10)-trien-17-one and (±)-6-oxa-13β-ethyl-2-methoxy-8α-gona-1.3.5(10)-trien-17-one was described.
The total synthesis of (±)-6-oxa-13β-ethyl-3-methoxy-8α-gona-1.3.5(10)-trien-17-one and (±)-6-oxa-13β-ethyl-2-methoxy-8α-gona-1.3.5(10)-trien-17-one was described.
1998, 9(3): 251-253
Abstract:
A convenient synthesis of various heterocyclic substituted ureidoalkylphosphonic acid diphenyl esters 3 is reported in this paper. a-Aminoalkylphosphonic acid diphenyl esters 1 reacted with triphosgene, and then treated with heterocyclic amines gave 3. Small amount of symmetric urylenediphosphonate 4 are isolated as side products.
A convenient synthesis of various heterocyclic substituted ureidoalkylphosphonic acid diphenyl esters 3 is reported in this paper. a-Aminoalkylphosphonic acid diphenyl esters 1 reacted with triphosgene, and then treated with heterocyclic amines gave 3. Small amount of symmetric urylenediphosphonate 4 are isolated as side products.
1998, 9(3): 255-256
Abstract:
A new poly (aryl ether ketone) was successfully synthesized by nucleophilic substitution of bis-1, 4-(4-chlorobenzoyl) benzene (BCBB) by 1, 2-dihydro-4-(4-hydroxy phenyl) (2H)-phthalazin-1-one (DHPZ) in appropriate condition. The polymer was characterized by FT-IR, 1H-NMR, DSC and TGA etc.
A new poly (aryl ether ketone) was successfully synthesized by nucleophilic substitution of bis-1, 4-(4-chlorobenzoyl) benzene (BCBB) by 1, 2-dihydro-4-(4-hydroxy phenyl) (2H)-phthalazin-1-one (DHPZ) in appropriate condition. The polymer was characterized by FT-IR, 1H-NMR, DSC and TGA etc.
1998, 9(3): 257-258
Abstract:
A novel poly (ether sulfone ketone) containing the phthalazinone moiety was prepared by the reaction of 4-)4-hydroxyphenyl) (2H) phthalazin-l-one with activated dichloro-monomers. The polymer was characterized by FT-IR, 1H-NMR, DSC, TGA and X-ray diffraction.
A novel poly (ether sulfone ketone) containing the phthalazinone moiety was prepared by the reaction of 4-)4-hydroxyphenyl) (2H) phthalazin-l-one with activated dichloro-monomers. The polymer was characterized by FT-IR, 1H-NMR, DSC, TGA and X-ray diffraction.
1998, 9(3): 259-260
Abstract:
A C/D ring synthon of vitamin D is readily obtained from cholesteryl acetate via oxidation, elimination of acetoxy group and Norrish type Ⅱ photochemical reaction.
A C/D ring synthon of vitamin D is readily obtained from cholesteryl acetate via oxidation, elimination of acetoxy group and Norrish type Ⅱ photochemical reaction.
1998, 9(3): 261-262
Abstract:
The tricyclic compound is constructed via intramolecular Diels-Alder reaction. It might serve as the important intermediate for the total synthesis of hainanolide. The isolation and structures of three by-products were also described.
The tricyclic compound is constructed via intramolecular Diels-Alder reaction. It might serve as the important intermediate for the total synthesis of hainanolide. The isolation and structures of three by-products were also described.
1998, 9(3): 263-264
Abstract:
Using amino-poly(ethylene glycol) and amino-propyl silica gel as initiator cores, two dendrimers were prepared by a two-step procedure. The progress of dendrimers during each step was monitored by infrared spectroscopy and elemental analysis. Papain was crosslinked to the solid dendrimer with silica gel core by glutaraldehyde, and the enzymatic activity of the immobilized papain kept almost unchanged after repeated usage for fifteen times.
Using amino-poly(ethylene glycol) and amino-propyl silica gel as initiator cores, two dendrimers were prepared by a two-step procedure. The progress of dendrimers during each step was monitored by infrared spectroscopy and elemental analysis. Papain was crosslinked to the solid dendrimer with silica gel core by glutaraldehyde, and the enzymatic activity of the immobilized papain kept almost unchanged after repeated usage for fifteen times.
1998, 9(3): 265-268
Abstract:
The aryl moiety which was bonded as a functional group on the primary alcohol side of β-CD or the secondary alcohol side of β-CD or the secondary alcohol side of β-CD with an ethylenediamino chain could show remarkable different molecular recognition abilities in the complexation with small molecular guests such as alkanes, cycloketones etc.
The aryl moiety which was bonded as a functional group on the primary alcohol side of β-CD or the secondary alcohol side of β-CD or the secondary alcohol side of β-CD with an ethylenediamino chain could show remarkable different molecular recognition abilities in the complexation with small molecular guests such as alkanes, cycloketones etc.
1998, 9(3): 269-272
Abstract:
A tetranuclear complex[CO(Ⅲ)2(L)2(AcO)2(OH)](AcO)(2I)4H2O (L=N-ferrocenyl-methyl-1, 4, 7-triaza-cyclononane) was prepared from ligand L HI and its crystal structure was determined. The crystal exists in P21/a space group and its cell parameters are α=14.285(3)Å, b=19.888(3)Å, c=19.133(3)Å; β=109.12(2)°; V=5135.8Å3; Z=4. Electrochemical investigation reveals that the oxidation potential of ferrocenyl group in 1 has a 0.11V-positive-shift from that of the ferrocenyl group in L. HI.
A tetranuclear complex[CO(Ⅲ)2(L)2(AcO)2(OH)](AcO)(2I)4H2O (L=N-ferrocenyl-methyl-1, 4, 7-triaza-cyclononane) was prepared from ligand L HI and its crystal structure was determined. The crystal exists in P21/a space group and its cell parameters are α=14.285(3)Å, b=19.888(3)Å, c=19.133(3)Å; β=109.12(2)°; V=5135.8Å3; Z=4. Electrochemical investigation reveals that the oxidation potential of ferrocenyl group in 1 has a 0.11V-positive-shift from that of the ferrocenyl group in L. HI.
1998, 9(3): 273-276
Abstract:
A new special property of DNA was found. It can remarkably catalyze the electrooxidation of catecholamine neurotransmitters. The electrocatalytic activity of DNA towards catecholamine neurotransmitters can be attributed to the interaction between DNA and the neurotransmitters.
A new special property of DNA was found. It can remarkably catalyze the electrooxidation of catecholamine neurotransmitters. The electrocatalytic activity of DNA towards catecholamine neurotransmitters can be attributed to the interaction between DNA and the neurotransmitters.
1998, 9(3): 277-279
Abstract:
A new triazene reagent 1-(6-ethoxyl-2-benzothiazolyl)-3-(4-nitrophenyl)-triazene (EtOBTNPT) has been synthesized. The colour reaction of EtOBTNPT with Hg(Ⅱ) has been studied. At pH=10.1-10.7, in the presence of Triton X-100, the reagent with Hg(Ⅱ) forms an orange-yellow complex with high sensitivity. The molar absorptivity is 2.38×105L·mol-1·cm-1. Beer's law is obeyed for Hg(Ⅱ) in the range of 0-7μg/25ml.
A new triazene reagent 1-(6-ethoxyl-2-benzothiazolyl)-3-(4-nitrophenyl)-triazene (EtOBTNPT) has been synthesized. The colour reaction of EtOBTNPT with Hg(Ⅱ) has been studied. At pH=10.1-10.7, in the presence of Triton X-100, the reagent with Hg(Ⅱ) forms an orange-yellow complex with high sensitivity. The molar absorptivity is 2.38×105L·mol-1·cm-1. Beer's law is obeyed for Hg(Ⅱ) in the range of 0-7μg/25ml.
1998, 9(3): 277-230
Abstract:
Electrochemical reduction of zearalenone 1 and its derivatives was described. The ratio of a-and b-zearalanol 2 obtained by electrochemical reduction reached 8:1, much higher tan that obtained from catalytic hydrogenation. In addition to of the normal reduction products a rearranged product 5 was isolated. The reduction was supposed to be a electrocatalytical reaction.
Electrochemical reduction of zearalenone 1 and its derivatives was described. The ratio of a-and b-zearalanol 2 obtained by electrochemical reduction reached 8:1, much higher tan that obtained from catalytic hydrogenation. In addition to of the normal reduction products a rearranged product 5 was isolated. The reduction was supposed to be a electrocatalytical reaction.
1998, 9(3): 281-285
Abstract:
A sensitive HPLC method for the detection of amino acids with pre-column fluorescence derivatization with carbazole-9-yl-acetyl chloride has been developed. This method, in conjunction with a multi-gradient program, offers baseline resolution of the common CRAC-amino acids from a linear acetonitrile gradient. Separation of amino acid derivatives was obtained on a reversed-phase C18 column. Derivatization and chromatographic conditions were optimized. Amino acid derivatives were eluted in 40 min with good reproducibility. The relative standard deviations (n=6) at an analytical concentration of 100 pmol are <4%. The methods described are also suitable for the analysis of amino acids in different biological samples.
A sensitive HPLC method for the detection of amino acids with pre-column fluorescence derivatization with carbazole-9-yl-acetyl chloride has been developed. This method, in conjunction with a multi-gradient program, offers baseline resolution of the common CRAC-amino acids from a linear acetonitrile gradient. Separation of amino acid derivatives was obtained on a reversed-phase C18 column. Derivatization and chromatographic conditions were optimized. Amino acid derivatives were eluted in 40 min with good reproducibility. The relative standard deviations (n=6) at an analytical concentration of 100 pmol are <4%. The methods described are also suitable for the analysis of amino acids in different biological samples.
1998, 9(3): 287-289
Abstract:
A simple and selective method for the determination of epinephrine is put forward, which is an improved modification of the trihydroxyindole method. Experiment indicated that in borax buffer (pH=8.7) and with mercaptoethanol as the reducing reagent, dopa and dopamine did not form fluorescence products, so it is possible to determine epinephrine selectively.
A simple and selective method for the determination of epinephrine is put forward, which is an improved modification of the trihydroxyindole method. Experiment indicated that in borax buffer (pH=8.7) and with mercaptoethanol as the reducing reagent, dopa and dopamine did not form fluorescence products, so it is possible to determine epinephrine selectively.
1998, 9(3): 291-294
Abstract:
Applying Fourier transform technique to deduction of background and noise on dE/dt-t curve, a new electrochemical method, high order harmonic oscillographic chronopotentiometry, is proposed in this paper.
Applying Fourier transform technique to deduction of background and noise on dE/dt-t curve, a new electrochemical method, high order harmonic oscillographic chronopotentiometry, is proposed in this paper.
1998, 9(3): 295-298
Abstract:
Abstract The solubilities of a number of solid solutes in supercritical CO2 have been correlated using the model proposed in previous paper. The numbers of CO2 in each CO2-solute cluster and the local density of the CO2 in the clusters are predicted using the model. The results calculated agree fairly well with the experimental data.
Abstract The solubilities of a number of solid solutes in supercritical CO2 have been correlated using the model proposed in previous paper. The numbers of CO2 in each CO2-solute cluster and the local density of the CO2 in the clusters are predicted using the model. The results calculated agree fairly well with the experimental data.
1998, 9(3): 299-303
Abstract:
Molecule dynamics simulation was used on HPT(2, 3, 6, 7, 10, 11-hexa-n-pentyloxy-triphenylene), which is a discotic liquid crystal. From analyzing the energy and displacement varying with the temperature, the phase transition temperature of PM6MPP can be predicted. The deviations of Tg, Tm and Ti due to the MD time scale are small enough that it should be possibly used to predict the material properties especially when more powerful computers are available.
Molecule dynamics simulation was used on HPT(2, 3, 6, 7, 10, 11-hexa-n-pentyloxy-triphenylene), which is a discotic liquid crystal. From analyzing the energy and displacement varying with the temperature, the phase transition temperature of PM6MPP can be predicted. The deviations of Tg, Tm and Ti due to the MD time scale are small enough that it should be possibly used to predict the material properties especially when more powerful computers are available.
1998, 9(3): 305-306
Abstract:
The electrochemical behavior of PPV/PEO blend with different dopants was investigated by cyclic voltammetry. The p-doping process is electrochemically quasi-reversible while the n-doping is irreversible. The band gap of the blend obtained by the cyclic voltammetry is 2.45 eV, which is the same with that of pure PPV.
The electrochemical behavior of PPV/PEO blend with different dopants was investigated by cyclic voltammetry. The p-doping process is electrochemically quasi-reversible while the n-doping is irreversible. The band gap of the blend obtained by the cyclic voltammetry is 2.45 eV, which is the same with that of pure PPV.
1998, 9(3): 307-310
Abstract:
In this letter, the self-assembling process of thioglycollic acid on gold in aqueous solutions was studied by QCM technique. Frequency information suggests bilayer or multilayer adsorbate formation in 0.5 mol/L KCl solution but only monolayer one in 0.5 mol/L KOH solution. This phenomenon is explained by hydrogen bond effect.
In this letter, the self-assembling process of thioglycollic acid on gold in aqueous solutions was studied by QCM technique. Frequency information suggests bilayer or multilayer adsorbate formation in 0.5 mol/L KCl solution but only monolayer one in 0.5 mol/L KOH solution. This phenomenon is explained by hydrogen bond effect.
1998, 9(3): 311-314
Abstract:
Fluorescence spectra of the sensitizing dye/TiO2 bilayer films were studied. Charge-transfer complexes were formed in the above bilayer.
Fluorescence spectra of the sensitizing dye/TiO2 bilayer films were studied. Charge-transfer complexes were formed in the above bilayer.
1998, 9(3): 315-318
Abstract:
The film by tetraphenyIporphyrin((TPP)H2) vapor deposition on iron was investigated by means of XPS, SEM and visible spectroscopy. N(1s) binding energy characteristic of (TPP)H2 was gained directly from the deposited samples. N(1s) binding energy of the surface was greatly changed after the deposited sample was washed with solvent. It is indicated that the deposited film is composed of an outer-layer of physically adsorbed (TPP)H2, and an inner-layer of chemically modified (TPP)H2.
The film by tetraphenyIporphyrin((TPP)H2) vapor deposition on iron was investigated by means of XPS, SEM and visible spectroscopy. N(1s) binding energy characteristic of (TPP)H2 was gained directly from the deposited samples. N(1s) binding energy of the surface was greatly changed after the deposited sample was washed with solvent. It is indicated that the deposited film is composed of an outer-layer of physically adsorbed (TPP)H2, and an inner-layer of chemically modified (TPP)H2.
1998, 9(3): 319-320
Abstract:
Molecular weight of polyethylene (PE) and its distribution were determined by PL-GPC210 at high temperature, 160℃ or 170℃. The thermostability of PE at high temperature was discussed and its real molecular weight can be obtained.
Molecular weight of polyethylene (PE) and its distribution were determined by PL-GPC210 at high temperature, 160℃ or 170℃. The thermostability of PE at high temperature was discussed and its real molecular weight can be obtained.
