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1999 Volume 10 Issue 8
1999, 10(8): 623-624
Abstract:
Under the irradiation of medium pressure mercury lamp(MPML)the photolysis of 2-methoxycyosine (MAP) in phosphate solution leads to the production of a novel compound C5H8N3O5P. The composition and structure of the compound has been identified by elemental analysis. EI-MS. UV. IR.1H.31P-NMR.
Under the irradiation of medium pressure mercury lamp(MPML)the photolysis of 2-methoxycyosine (MAP) in phosphate solution leads to the production of a novel compound C5H8N3O5P. The composition and structure of the compound has been identified by elemental analysis. EI-MS. UV. IR.1H.31P-NMR.
1999, 10(8): 625-628
Abstract:
2,3-Dihydro-2-phenyl-4-(4-methoxyphenyl)-1,5-benzothiazepine reacts with ethoxy-carbonyl carbene to give an unexpected compound 2,3-disubstituted-4H-1,4-benzothiazine Ⅲ. It was found to be a new rearrangement reaction and the structure of the product was confirmed by IR, NMR, MS.
2,3-Dihydro-2-phenyl-4-(4-methoxyphenyl)-1,5-benzothiazepine reacts with ethoxy-carbonyl carbene to give an unexpected compound 2,3-disubstituted-4H-1,4-benzothiazine Ⅲ. It was found to be a new rearrangement reaction and the structure of the product was confirmed by IR, NMR, MS.
1999, 10(8): 629-632
Abstract:
Modest to high diastereoselectivites have been observed in the conjugate addition of functionalized alcohols to chiral (E)-nitroalkene 1 depending on the presence of metal catalysts at low temperature. The results indicated that the anti-form had been preferred in all cases.
Modest to high diastereoselectivites have been observed in the conjugate addition of functionalized alcohols to chiral (E)-nitroalkene 1 depending on the presence of metal catalysts at low temperature. The results indicated that the anti-form had been preferred in all cases.
1999, 10(8): 633-636
Abstract:
o-Bromomethylbenzylidenemalononitrile 4 is reduced by 1-benzyl-1,4-dihydronicotinamide (BNAH, 1) to give 2,2-indanedicarbonitrile 6 and p-bromomethylbenzylidene malononitrile 5 is reduced by BNAH to give 7 and 8 by hydride transfer mechanism.
o-Bromomethylbenzylidenemalononitrile 4 is reduced by 1-benzyl-1,4-dihydronicotinamide (BNAH, 1) to give 2,2-indanedicarbonitrile 6 and p-bromomethylbenzylidene malononitrile 5 is reduced by BNAH to give 7 and 8 by hydride transfer mechanism.
1999, 10(8): 637-640
Abstract:
The procedure for the ring enlargement of N-heterocycles with the net result of CH2 insertion was successfully carried out with certain alkaloids such as tetrahydroberberine and strychnine.
The procedure for the ring enlargement of N-heterocycles with the net result of CH2 insertion was successfully carried out with certain alkaloids such as tetrahydroberberine and strychnine.
1999, 10(8): 641-642
Abstract:
α-Selenoesters and α-thiolesters are synthesized via reactions of α-bromoesters with diselenides and disulfides promoted by Sm/SbCl3 system in aqueous media in moderate to good yields.
α-Selenoesters and α-thiolesters are synthesized via reactions of α-bromoesters with diselenides and disulfides promoted by Sm/SbCl3 system in aqueous media in moderate to good yields.
1999, 10(8): 643-646
Abstract:
Substituted pyrazolylpyrazoles were synthesized through the reaction of hydrazine hydrate and α-oxo-(3,5-dimethyl-lH-pyrazole-1一yl) ketene S,S-and N.S-acetals, which were obtained from α-oxo-(3,5-dimethyl-lH-pyrazole-l-yl) acetophenone. Pyrazolylpyrazole was also prepared via α-oxo ketene N,O-acetal by way of ring chain transformation.
Substituted pyrazolylpyrazoles were synthesized through the reaction of hydrazine hydrate and α-oxo-(3,5-dimethyl-lH-pyrazole-1一yl) ketene S,S-and N.S-acetals, which were obtained from α-oxo-(3,5-dimethyl-lH-pyrazole-l-yl) acetophenone. Pyrazolylpyrazole was also prepared via α-oxo ketene N,O-acetal by way of ring chain transformation.
1999, 10(8): 647-650
Abstract:
5-Isoxazolamines were synthesized from a-cyano-p-vitro compounds by treatment with titanium trichloride.
5-Isoxazolamines were synthesized from a-cyano-p-vitro compounds by treatment with titanium trichloride.
1999, 10(8): 651-652
Abstract:
The sythesis of 2S-hydroxymethyl-3R. 4R-dihydroxypyrrolidine from D-arabinose was described in this paper.
The sythesis of 2S-hydroxymethyl-3R. 4R-dihydroxypyrrolidine from D-arabinose was described in this paper.
1999, 10(8): 653-656
Abstract:
The natural product(±)-cordatolide A has been synthesized by a four-step approach starting from phloroglucinol. including Pechmann reaction, Friedel-Crafts acylation, cyclization, chromenylation and Luche reduction.
The natural product(±)-cordatolide A has been synthesized by a four-step approach starting from phloroglucinol. including Pechmann reaction, Friedel-Crafts acylation, cyclization, chromenylation and Luche reduction.
1999, 10(8): 657-658
Abstract:
Six tricyclic compounds containing C3, C4 double bonds were oxidized with singlet oxygen. Different regio-selectivity was found with regard to steric hinderence.
Six tricyclic compounds containing C3, C4 double bonds were oxidized with singlet oxygen. Different regio-selectivity was found with regard to steric hinderence.
1999, 10(8): 659-660
Abstract:
A new near-infrared fluorescent dye, 9-N-(2-hydroxyethyl)-N-methylamino-6-carbethoxy-SH-benzo[a]phenoxazin-5-one 1, was prepared from the reaction of N-(2-hydroxy-ethyl)-N-methyl-4-nitrosoaniline hydrochloride and ethyl 1,3-dihydroxynaphthoate. Five more fluorescent compounds were synthesized by the reaction of the resulting dye 1 with appropriate amino acid or carboxylic acids.
A new near-infrared fluorescent dye, 9-N-(2-hydroxyethyl)-N-methylamino-6-carbethoxy-SH-benzo[a]phenoxazin-5-one 1, was prepared from the reaction of N-(2-hydroxy-ethyl)-N-methyl-4-nitrosoaniline hydrochloride and ethyl 1,3-dihydroxynaphthoate. Five more fluorescent compounds were synthesized by the reaction of the resulting dye 1 with appropriate amino acid or carboxylic acids.
1999, 10(8): 661-664
Abstract:
Heteroatom amyl-substituted heterocyclic ketene aminals 1 reacted with 2,3,4,6-tetra-O-acetyl-α-D-glucopyranosyl bromide 2 under the catalysis of Hg(CN)2 or CaH2 to give E-or Z-O-glycosides of heterocyclic ketene aminals 3 or 4 in moderate yields.
Heteroatom amyl-substituted heterocyclic ketene aminals 1 reacted with 2,3,4,6-tetra-O-acetyl-α-D-glucopyranosyl bromide 2 under the catalysis of Hg(CN)2 or CaH2 to give E-or Z-O-glycosides of heterocyclic ketene aminals 3 or 4 in moderate yields.
1999, 10(8): 665-666
Abstract:
The synthesis of eight new arsamacrocyclic Polyethers was described. The structures of these compounds were characterized by elemental analysis, IR, 1H-NMR and MS.
The synthesis of eight new arsamacrocyclic Polyethers was described. The structures of these compounds were characterized by elemental analysis, IR, 1H-NMR and MS.
1999, 10(8): 667-670
Abstract:
A novel bi-functional photorefractive acrylate polymer with pendant carbazolyl groups and azo derivatives as side chains was synthesized. Photorefractive experiments showed a high twobeam coupling gain coefficient of 93 cm-1, diffraction efficiency of 12% and electro-optic coefficient of 26 pm/V were obtained.
A novel bi-functional photorefractive acrylate polymer with pendant carbazolyl groups and azo derivatives as side chains was synthesized. Photorefractive experiments showed a high twobeam coupling gain coefficient of 93 cm-1, diffraction efficiency of 12% and electro-optic coefficient of 26 pm/V were obtained.
1999, 10(8): 671-672
Abstract:
A new azafluorenone (onychine) alkaloid, 6,7-dimethoxy-5-hydroxy-onychine. was isolated from the stem and branch of Alphonsea monogyma. Its structure was established mainly on the basis of spectral analysis.
A new azafluorenone (onychine) alkaloid, 6,7-dimethoxy-5-hydroxy-onychine. was isolated from the stem and branch of Alphonsea monogyma. Its structure was established mainly on the basis of spectral analysis.
1999, 10(8): 673-674
Abstract:
A new ent-kaurane diterpene was isolated from the rhizome of Aralia fargesii. On the basis of chemical and spectral evidences, its structure was established as 16a-hydroxy-l7-isovaleroyloxy-ent-kauran-l9-oic acid.
A new ent-kaurane diterpene was isolated from the rhizome of Aralia fargesii. On the basis of chemical and spectral evidences, its structure was established as 16a-hydroxy-l7-isovaleroyloxy-ent-kauran-l9-oic acid.
1999, 10(8): 675-676
Abstract:
A new oxoaporphine alkaloid, 1,2-methylene-dioxy-8-hydroxy-5-methoxy oxoaporphine, was isolated from the stem barks of Alphonsea mollis. Its structure was established on the basis of spectral analysis and chemical corcelation
A new oxoaporphine alkaloid, 1,2-methylene-dioxy-8-hydroxy-5-methoxy oxoaporphine, was isolated from the stem barks of Alphonsea mollis. Its structure was established on the basis of spectral analysis and chemical corcelation
1999, 10(8): 677-678
Abstract:
The stability constant for complex of Pr(Ⅲ) with adrenaline has been determined by potentiometric titration under biological conditions (37℃ and O.15mo1/L NaCI). The absorption spectra of the Pr(III)-adrenaline system exhibit characteristic bands of Pr(Ⅲ) at lower pH values. However, the charge transfer band which is due to the coordination of Pr(Ⅲ) with adrenaline has been observed at higher pH values.
The stability constant for complex of Pr(Ⅲ) with adrenaline has been determined by potentiometric titration under biological conditions (37℃ and O.15mo1/L NaCI). The absorption spectra of the Pr(III)-adrenaline system exhibit characteristic bands of Pr(Ⅲ) at lower pH values. However, the charge transfer band which is due to the coordination of Pr(Ⅲ) with adrenaline has been observed at higher pH values.
1999, 10(8): 679-682
Abstract:
Three kinds of pyrazolines were designed and synthesized. Their structures were elucidated by IR, 1HNMR MS, UV and elemental analysis. Their luminescent properties were determined, which indicated that they had strong blue fluorescent properties. One of them was designed to have good film formation. All the three kinds of pyrazolines can be used as blue organic electroluminescence materials (OELMs)
Three kinds of pyrazolines were designed and synthesized. Their structures were elucidated by IR, 1HNMR MS, UV and elemental analysis. Their luminescent properties were determined, which indicated that they had strong blue fluorescent properties. One of them was designed to have good film formation. All the three kinds of pyrazolines can be used as blue organic electroluminescence materials (OELMs)
1999, 10(8): 683-684
Abstract:
A new soluble subphthalocyanine was first prepared and its fluorescence property was investigated. It exhibited both S1 and S2 emissions, of which the quantum yields and the lifetimes were measured.
A new soluble subphthalocyanine was first prepared and its fluorescence property was investigated. It exhibited both S1 and S2 emissions, of which the quantum yields and the lifetimes were measured.
1999, 10(8): 685-688
Abstract:
The titled compound 1 as well as compounds 2 and with similar chemical structures were prepared and characterized. The magnetic properties of 1 were investigated with SQUID (MPMS, quantum design) magnetometer. Studies with Langmuir-Blodgett (LB) technique indicated that stable condensed film of 1 could be formed at air-water interface and could be transferred onto various solid substrate under suitable conditions.
The titled compound 1 as well as compounds 2 and with similar chemical structures were prepared and characterized. The magnetic properties of 1 were investigated with SQUID (MPMS, quantum design) magnetometer. Studies with Langmuir-Blodgett (LB) technique indicated that stable condensed film of 1 could be formed at air-water interface and could be transferred onto various solid substrate under suitable conditions.
1999, 10(8): 689-690
Abstract:
Thermodynamic and kinetic properties of the tautomerism of an indoline spiropyran in compressed CO2-ethanol mixture were studied by UV-Vis spectroscopy at 298.15 K, 303.15 K, and 308.15 K. It was found that the composition of the mixture affects the equilibrium constant and the rate constant significantly.
Thermodynamic and kinetic properties of the tautomerism of an indoline spiropyran in compressed CO2-ethanol mixture were studied by UV-Vis spectroscopy at 298.15 K, 303.15 K, and 308.15 K. It was found that the composition of the mixture affects the equilibrium constant and the rate constant significantly.
1999, 10(8): 691-692
Abstract:
In this paper several rare earth oxides were added into methanol synthesis catalyst by solid-mixing method to improve the activity of methanol synthesis catalyst. Nd2O3, CeO2, La2O3 and Sm2O3 decrease the catalyst activity, while Pr2O3, Gd2O3 and Eu2O3 increase the methanol yield.
In this paper several rare earth oxides were added into methanol synthesis catalyst by solid-mixing method to improve the activity of methanol synthesis catalyst. Nd2O3, CeO2, La2O3 and Sm2O3 decrease the catalyst activity, while Pr2O3, Gd2O3 and Eu2O3 increase the methanol yield.
1999, 10(8): 693-696
Abstract:
1. 2-bis(3-Methylbenzo[b]thiophen-2-yl)cycloalkene derivatives 3a, 3b and 1-(2-methylbenzo[b]thiophen-3-yl)-2-(3-methylbenzo[b]thiophen-2-yl)cyclohexene 9 were synthesized. The obtained compounds exhibited photochromic property and the absorption bands of the colored forms 4a. 4b and 10 centered between 360-440 nm thus possessing the sensitivity at the wavelength of the newly developed InGaN diode laser.
1. 2-bis(3-Methylbenzo[b]thiophen-2-yl)cycloalkene derivatives 3a, 3b and 1-(2-methylbenzo[b]thiophen-3-yl)-2-(3-methylbenzo[b]thiophen-2-yl)cyclohexene 9 were synthesized. The obtained compounds exhibited photochromic property and the absorption bands of the colored forms 4a. 4b and 10 centered between 360-440 nm thus possessing the sensitivity at the wavelength of the newly developed InGaN diode laser.
1999, 10(8): 697-700
Abstract:
The reported X-ray structure and magnetochemical properties of [Mn6O2 (OCPh)10 (CH3CN)4], effectively derived from [NBu4][Mn402 (O2CPh)9 (H2O)] with equivalent of tren in CH3CN is shown.
The reported X-ray structure and magnetochemical properties of [Mn6O2 (OCPh)10 (CH3CN)4], effectively derived from [NBu4][Mn402 (O2CPh)9 (H2O)] with equivalent of tren in CH3CN is shown.
1999, 10(8): 701-704
Abstract:
Catalytic hydrogenation of diacetyl monoxime to tetramethylpyrazine, by the homogeneous catalysts generated in situ from some transition metal chlorides with triphenylphosphine in ethanol under H2 pressure of 0.6~4.6 MPa at 100~150℃, has been studied. The optimum H2 partial pressure was observed at about 1.3 MPa. The maximum conversion of diacetyl monoxime and yield of tetramethylpyrazine were 97% and 90%, respectively.
Catalytic hydrogenation of diacetyl monoxime to tetramethylpyrazine, by the homogeneous catalysts generated in situ from some transition metal chlorides with triphenylphosphine in ethanol under H2 pressure of 0.6~4.6 MPa at 100~150℃, has been studied. The optimum H2 partial pressure was observed at about 1.3 MPa. The maximum conversion of diacetyl monoxime and yield of tetramethylpyrazine were 97% and 90%, respectively.
1999, 10(8): 705-706
Abstract:
Cyclohexanephosphonyl heterupulyundecatungstates of formula [C6H11P(O)]2 Xn+W11O39(8-n)-(Xn+=P5+, Si4+, B3+, Ga3+)have been prepared. puritied and characterized by elemental analysis. 1R and 1H. 31P and 183W NMR.
Cyclohexanephosphonyl heterupulyundecatungstates of formula [C6H11P(O)]2 Xn+W11O39(8-n)-(Xn+=P5+, Si4+, B3+, Ga3+)have been prepared. puritied and characterized by elemental analysis. 1R and 1H. 31P and 183W NMR.
1999, 10(8): 707-708
Abstract:
The first reported (B1-xMx)PO4 (M=Mn. Fe. Co. Ni. Cu) compounds were synthesized by high temperature solid state methods and the structures refined from X-ray powder data. The transition metal substitutions on the boron site stabilized the structure to the orthorhombic low-cristobalite type with average volumes per tetrahedral unit 300% larger than that in BPO4 and novel catalytic properties are expected. The magnetic data indicate the 3+ valences for the metals.
The first reported (B1-xMx)PO4 (M=Mn. Fe. Co. Ni. Cu) compounds were synthesized by high temperature solid state methods and the structures refined from X-ray powder data. The transition metal substitutions on the boron site stabilized the structure to the orthorhombic low-cristobalite type with average volumes per tetrahedral unit 300% larger than that in BPO4 and novel catalytic properties are expected. The magnetic data indicate the 3+ valences for the metals.
1999, 10(8): 709-712
Abstract:
The phosphors BaAl2O4Eu2+. RE (RE=Dy,Ho) have been prepared by the microwave heating technique. The long-lasting phosphorescence in the phosphors of the barium aluminate activated with europium and other rare earths has been observed for the first limy
The phosphors BaAl2O4Eu2+. RE (RE=Dy,Ho) have been prepared by the microwave heating technique. The long-lasting phosphorescence in the phosphors of the barium aluminate activated with europium and other rare earths has been observed for the first limy
1999, 10(8): 713-716
Abstract:
Thc effeet of Al2+. NH4, Na+ on the Ti content in the pmparation of Ti-ZSM-5 by the isomorphous substitution of ZSM-5 using gaseous TiCl4 as titanium resource has heen im estigatcd It is surprisingly found that although the direef ratio exists heween the Ti conmnt and the content of the skeletal Al:y=(0.08x2+0.57x+1.23 (hereyrepresents TiO2% and xreprcwnts Al2O3%). but the catalytic activities of Ti-ZSM-5 for the oxidation of styrene sharply rise with the decrease of TiO2%. The skeletal Al hinders the Ti incorporation into the framework of molmular sim, characterised by FT-IR chniyuc. At the same time. NH4+ ion has no etlcct on the Ti incorporation. but Na ion does.
Thc effeet of Al2+. NH4, Na+ on the Ti content in the pmparation of Ti-ZSM-5 by the isomorphous substitution of ZSM-5 using gaseous TiCl4 as titanium resource has heen im estigatcd It is surprisingly found that although the direef ratio exists heween the Ti conmnt and the content of the skeletal Al:y=(0.08x2+0.57x+1.23 (hereyrepresents TiO2% and xreprcwnts Al2O3%). but the catalytic activities of Ti-ZSM-5 for the oxidation of styrene sharply rise with the decrease of TiO2%. The skeletal Al hinders the Ti incorporation into the framework of molmular sim, characterised by FT-IR chniyuc. At the same time. NH4+ ion has no etlcct on the Ti incorporation. but Na ion does.
