Login In
1999 Volume 10 Issue 6
1999, 10(6): 435-436
Abstract:
Dicyclohexylmethyl diazoacetate was synthesized in excellent yield from the corresponding glycinate. which was derived in high yield from dicyclohexylmethyl chloroacetatc via azide substitutuion. and reduction.
Dicyclohexylmethyl diazoacetate was synthesized in excellent yield from the corresponding glycinate. which was derived in high yield from dicyclohexylmethyl chloroacetatc via azide substitutuion. and reduction.
1999, 10(6): 437-440
Abstract:
The insertion of elemental selenium into the Csp2-Zr bond of alkenylchloro-zirconocenes affords (E)-vinylseleno zirconocenes, which were trapped by alkyl halides giving (E)-vinylic selenides in moderate to good yields.
The insertion of elemental selenium into the Csp2-Zr bond of alkenylchloro-zirconocenes affords (E)-vinylseleno zirconocenes, which were trapped by alkyl halides giving (E)-vinylic selenides in moderate to good yields.
1999, 10(6): 441-442
Abstract:
The asymmetric Darzen's condensation of aldehydes with α-chloroacetates of some naturally occurring or synthetic chiral alcohols was described. The de% of products fell over the range of 4.78% to 99%.
The asymmetric Darzen's condensation of aldehydes with α-chloroacetates of some naturally occurring or synthetic chiral alcohols was described. The de% of products fell over the range of 4.78% to 99%.
1999, 10(6): 443-444
Abstract:
d,l-α-lbcopherol(vitamin E) is found to be synthesized by condensing trimcthylhydroquinone with isophytol catalyzed by heteropoly acids(HPA) H2PW12O40 and H2PMo12O40 at room temperature. These HPA are efficient catalysts for the synthesis of d,l-α-Tocophcrol and can easily be separated from the reaction mixture and reused.
d,l-α-lbcopherol(vitamin E) is found to be synthesized by condensing trimcthylhydroquinone with isophytol catalyzed by heteropoly acids(HPA) H2PW12O40 and H2PMo12O40 at room temperature. These HPA are efficient catalysts for the synthesis of d,l-α-Tocophcrol and can easily be separated from the reaction mixture and reused.
1999, 10(6): 445-446
Abstract:
Keeping in view the biological activities of 1,3,2-dioxaphosphorinane-2-one and oxime esters, some compounds possessing these two moieties have been synthesised. The contieurational assignment and the ratio of cis trans diastereomers of target products were pertbrmed on basis of 1H NMR. 31P NMR and confirmed by X-ray diffraction analysis.
Keeping in view the biological activities of 1,3,2-dioxaphosphorinane-2-one and oxime esters, some compounds possessing these two moieties have been synthesised. The contieurational assignment and the ratio of cis trans diastereomers of target products were pertbrmed on basis of 1H NMR. 31P NMR and confirmed by X-ray diffraction analysis.
1999, 10(6): 447-448
Abstract:
Reaction of 1,5-benzothiazepine with N-proteeted glycine gives new α-amino-β-lactam dvriwtivcs of 1,5-benzothiazepine. The configuratiun and conformation of the product were contirmed by x-ray diffraction. The result further reveals that the reaction of 1,5-benzothiazepines with derivatives of carboxylic acid is stereospecific.
Reaction of 1,5-benzothiazepine with N-proteeted glycine gives new α-amino-β-lactam dvriwtivcs of 1,5-benzothiazepine. The configuratiun and conformation of the product were contirmed by x-ray diffraction. The result further reveals that the reaction of 1,5-benzothiazepines with derivatives of carboxylic acid is stereospecific.
1999, 10(6): 449-452
Abstract:
(+)8-O-Cinnamyl-p-chlorogoniotriol (p-chlorohowiinol A) and its analogues have been synthesised in nine steps from α-D-glucoheptonic-γ-lactonc. Pharmacological tests showed that most of the compounds possessed antitumor activities toward tumor cell in voro.
(+)8-O-Cinnamyl-p-chlorogoniotriol (p-chlorohowiinol A) and its analogues have been synthesised in nine steps from α-D-glucoheptonic-γ-lactonc. Pharmacological tests showed that most of the compounds possessed antitumor activities toward tumor cell in voro.
1999, 10(6): 453-456
Abstract:
Teatment of 3-acetylpseudaconie 6 and 3. 13-diacetylyunnaconitine 9 with NBS/acetone-H2O (2:1) at room temperature produced corresponding imine derivatives 8 and 10, respectively.in good yields. This is a novel simple and convenient method for preparation of the iminc compounds.
Teatment of 3-acetylpseudaconie 6 and 3. 13-diacetylyunnaconitine 9 with NBS/acetone-H2O (2:1) at room temperature produced corresponding imine derivatives 8 and 10, respectively.in good yields. This is a novel simple and convenient method for preparation of the iminc compounds.
1999, 10(6): 457-458
Abstract:
A new compound, methyl 4,6-O-benzylidene-α-D-glucopyranoside 2,3-cyclic phosphite ethyl ester was synthesized via the reaction of methyl 4,6-O-benzylidene-α-D-glucopyranoside and ethyl dichlorophosphite. Its structure was confirmed by NMR and MS spectral methods.
A new compound, methyl 4,6-O-benzylidene-α-D-glucopyranoside 2,3-cyclic phosphite ethyl ester was synthesized via the reaction of methyl 4,6-O-benzylidene-α-D-glucopyranoside and ethyl dichlorophosphite. Its structure was confirmed by NMR and MS spectral methods.
1999, 10(6): 459-462
Abstract:
A new binuclear bisphthalocyanine-tetrahydroxo(hexa-tetradecanobisphthalocyani-nato) disilicium is synthesized and characterized. and one of its important applications is introduced.
A new binuclear bisphthalocyanine-tetrahydroxo(hexa-tetradecanobisphthalocyani-nato) disilicium is synthesized and characterized. and one of its important applications is introduced.
1999, 10(6): 463-466
Abstract:
A new lycopodium alkaloid with a novel skeleton was isolated from Huperzia serrata Its structure was determined on the basis of spectral evidences.
A new lycopodium alkaloid with a novel skeleton was isolated from Huperzia serrata Its structure was determined on the basis of spectral evidences.
1999, 10(6): 467-468
Abstract:
It is the first reported that a new nitrogen-containing non-amino acid type organic component 1 isolated from one of the well known traditional Chinese herb medicines. Gastrodia eleta B1. Structure elucidation and unambiguous NMR assignments for the title compound were carried out mainly on the basis of 1D and 2D NMR experiments.
It is the first reported that a new nitrogen-containing non-amino acid type organic component 1 isolated from one of the well known traditional Chinese herb medicines. Gastrodia eleta B1. Structure elucidation and unambiguous NMR assignments for the title compound were carried out mainly on the basis of 1D and 2D NMR experiments.
1999, 10(6): 469-472
Abstract:
The discovery of COX-2 provides a novel target developing more ettective NSAIDs with fewer side effects. On the basis of results from the structure-activity relationships (SAR) of selective COX-2 inhibitors. we have designed and synthesized some promising compounds.
The discovery of COX-2 provides a novel target developing more ettective NSAIDs with fewer side effects. On the basis of results from the structure-activity relationships (SAR) of selective COX-2 inhibitors. we have designed and synthesized some promising compounds.
1999, 10(6): 473-476
Abstract:
A new triterpenoid saponin named escin IVe was isolated from the seeds of Aesculus chinensis. Its structure was established as 28-tigloylprotoaescigenin-3β-O-[β-D-glucopyranosyl(1-2)][β-D-glucopyranusyl (1-4)]-β-D-glucopyranosiduronic acid.
A new triterpenoid saponin named escin IVe was isolated from the seeds of Aesculus chinensis. Its structure was established as 28-tigloylprotoaescigenin-3β-O-[β-D-glucopyranosyl(1-2)][β-D-glucopyranusyl (1-4)]-β-D-glucopyranosiduronic acid.
1999, 10(6): 477-480
Abstract:
Four new Coumarins named Decursitin B. C. D, F have been isolated from traditional Chinese medicine-the root of Peacedanum decursivum. Their structures were elucidated by chemical evidences and spectral analysis.
Four new Coumarins named Decursitin B. C. D, F have been isolated from traditional Chinese medicine-the root of Peacedanum decursivum. Their structures were elucidated by chemical evidences and spectral analysis.
1999, 10(6): 481-484
Abstract:
Three novel bicyclic taxane diterpenoids with the rare 6/12-membered rings wereisolated from the need ies of Taxus chinensis var. mairei. The structures were established with the help of 1D and 2D NMR spectral analysis.
Three novel bicyclic taxane diterpenoids with the rare 6/12-membered rings wereisolated from the need ies of Taxus chinensis var. mairei. The structures were established with the help of 1D and 2D NMR spectral analysis.
1999, 10(6): 485-486
Abstract:
A new triterpene glycoside, 24S-cycloartane-3β,16β, 24, 25, 30-pentaol 3-O-(2-O-β-D-xylosyl)-β-D-xyloside was isolated from Thalictrum smithii. Its structure was determined by spectroscopic and chemical methods.
A new triterpene glycoside, 24S-cycloartane-3β,16β, 24, 25, 30-pentaol 3-O-(2-O-β-D-xylosyl)-β-D-xyloside was isolated from Thalictrum smithii. Its structure was determined by spectroscopic and chemical methods.
1999, 10(6): 487-490
Abstract:
A new sesquiterpene polyol ester was isolated from the leaves of Celastrus angulatus. Its structure was determined as 1β, 2β,9α-triacetoxy-8α-(α-hydroxyl-isobutyryloxy)-15-benzoyloxy-4α-hydroxy-dihydroagarofuran by means of NMR, MS and IR spectral analysis. Preliminary biological study on antitumor activity revealed that this compound showed strong nonselective cytotoxicity against four of the NCI panel cell lines.
A new sesquiterpene polyol ester was isolated from the leaves of Celastrus angulatus. Its structure was determined as 1β, 2β,9α-triacetoxy-8α-(α-hydroxyl-isobutyryloxy)-15-benzoyloxy-4α-hydroxy-dihydroagarofuran by means of NMR, MS and IR spectral analysis. Preliminary biological study on antitumor activity revealed that this compound showed strong nonselective cytotoxicity against four of the NCI panel cell lines.
1999, 10(6): 491-494
Abstract:
A new sesquiterpene lactone eupatoranolide was isolated from the flowers of Eupatorium adenophorum, its structure was elucidated as 2β-acetoxy-(7α. 9βH)-3,6(11)-cadinadien-12(7)-olide by spectral analysis.
A new sesquiterpene lactone eupatoranolide was isolated from the flowers of Eupatorium adenophorum, its structure was elucidated as 2β-acetoxy-(7α. 9βH)-3,6(11)-cadinadien-12(7)-olide by spectral analysis.
1999, 10(6): 495-498
Abstract:
A novel immunoassay method for methyltestosterone (MT) in serum was developed. The antigen of MT (AgMT)was synthesized by covalently bonding MT to BSA and raising its antibody (AbMT). AbMT was conjugated to poly-N-isopropylacrylamide (p-NIPAAm) to form AbMT bound thermally reversible hydrogel p-NIPAAm-AbMT. A competitive immunoassay method based on the competition of fluorescein isothiocyanate (FITC) labeled MT antigen (FITC-AgMT) and free MT with limited amount of p-NIPAAm-AbMT was established. The separation in the assay process was achieved by precipitation of the immuno-complex above its critical solution temperature. The detection limit for MT is 50 ng/ml. The recoveries of MT from human serum are satisfactory.
A novel immunoassay method for methyltestosterone (MT) in serum was developed. The antigen of MT (AgMT)was synthesized by covalently bonding MT to BSA and raising its antibody (AbMT). AbMT was conjugated to poly-N-isopropylacrylamide (p-NIPAAm) to form AbMT bound thermally reversible hydrogel p-NIPAAm-AbMT. A competitive immunoassay method based on the competition of fluorescein isothiocyanate (FITC) labeled MT antigen (FITC-AgMT) and free MT with limited amount of p-NIPAAm-AbMT was established. The separation in the assay process was achieved by precipitation of the immuno-complex above its critical solution temperature. The detection limit for MT is 50 ng/ml. The recoveries of MT from human serum are satisfactory.
1999, 10(6): 499-502
Abstract:
By using 1-methyl-2-formyl-5-Y-substituted pyrrole (4-nitrophenyl)hydrazones as a model for nitrogen-containing heterocyclic aromatic compounds, the emission wavelength[λmax(em) ] values of their fluorescence spectra have been measured. Correlation results show that the △Eem values are mainly affected by polar effects, but spin-delocalizatin effects also exist.
By using 1-methyl-2-formyl-5-Y-substituted pyrrole (4-nitrophenyl)hydrazones as a model for nitrogen-containing heterocyclic aromatic compounds, the emission wavelength[λmax(em) ] values of their fluorescence spectra have been measured. Correlation results show that the △Eem values are mainly affected by polar effects, but spin-delocalizatin effects also exist.
1999, 10(6): 503-504
Abstract:
The electronic structure of the molecular ion has been calculated by DV-Xα method. The calculated nitrogen atomic charge is high in negative. The frontier molecular orbitals are mainly composed of Mo and S atomic valence orbitals. Total density of state reveals that there are wide bands below and above the E1, energy.
The electronic structure of the molecular ion has been calculated by DV-Xα method. The calculated nitrogen atomic charge is high in negative. The frontier molecular orbitals are mainly composed of Mo and S atomic valence orbitals. Total density of state reveals that there are wide bands below and above the E1, energy.
1999, 10(6): 505-506
Abstract:
Two new Ru(phen)32+-based surfactants. Ru(phen)2(phenNHCO-C11)(PF6)2 and Ru(phen)2(phenNHCO-C17)(PF6)2, have been designed and synthesized, whose chemical structures were characterized by means of IR, 1H NMR and MS. Also, electrochemistry and fluorescence of them are reported.
Two new Ru(phen)32+-based surfactants. Ru(phen)2(phenNHCO-C11)(PF6)2 and Ru(phen)2(phenNHCO-C17)(PF6)2, have been designed and synthesized, whose chemical structures were characterized by means of IR, 1H NMR and MS. Also, electrochemistry and fluorescence of them are reported.
1999, 10(6): 507-510
Abstract:
The surface pressure-area isotherms of bilirubin (BR) monolayers at an air-water interface on subphases with and without metal ions were investigated. The formation of BR-metal complexes leads to changes in the shape of isotherms of BR and changes in UV-visible absorption spectra of the monolayer assemblies. In XPS spectra new XPS peaks assigned to the metal ions containing subphases appeared. Low-angle X-ray diffraction indicates this Y-type LB films of MBR were formed with bilayer spacing of ca. 2.1 nm.
The surface pressure-area isotherms of bilirubin (BR) monolayers at an air-water interface on subphases with and without metal ions were investigated. The formation of BR-metal complexes leads to changes in the shape of isotherms of BR and changes in UV-visible absorption spectra of the monolayer assemblies. In XPS spectra new XPS peaks assigned to the metal ions containing subphases appeared. Low-angle X-ray diffraction indicates this Y-type LB films of MBR were formed with bilayer spacing of ca. 2.1 nm.
1999, 10(6): 511-514
Abstract:
The structures of four isomeric forms of the model germylenoid, H2GeLiF. have been examined by ab initio MO theory. The most stable structure is suggested to be the p-complex 1. The other three species, three-membered ring 2, σ-complex 3 and tetrahedron 4, are also local minima on the potential energy surface, but are higher in energy.
The structures of four isomeric forms of the model germylenoid, H2GeLiF. have been examined by ab initio MO theory. The most stable structure is suggested to be the p-complex 1. The other three species, three-membered ring 2, σ-complex 3 and tetrahedron 4, are also local minima on the potential energy surface, but are higher in energy.
1999, 10(6): 515-518
Abstract:
Molecular Dynamics (MD) simulations of siliceous FAU-type zeolite were carried out at various temperatures, to investigate its thermal behaviors. From the study, we found that pure silicon faujasite showed different thermal behaviors below 1500K and above 1500K; its cell volume gradually shrinks with the rising of the temperature below 1500K, the cell volume of the zeolite changes little above 1500K.
Molecular Dynamics (MD) simulations of siliceous FAU-type zeolite were carried out at various temperatures, to investigate its thermal behaviors. From the study, we found that pure silicon faujasite showed different thermal behaviors below 1500K and above 1500K; its cell volume gradually shrinks with the rising of the temperature below 1500K, the cell volume of the zeolite changes little above 1500K.
1999, 10(6): 519-520
Abstract:
By optimizing the cystallization condition, a procedure for the synthesis of small crystallite reolite GSM-5 was developed. Compared with the larger crystallite GSM-5, the smaller one exhibits higher catalytic performance in aromatiration reaction of propane.
By optimizing the cystallization condition, a procedure for the synthesis of small crystallite reolite GSM-5 was developed. Compared with the larger crystallite GSM-5, the smaller one exhibits higher catalytic performance in aromatiration reaction of propane.
1999, 10(6): 521-524
Abstract:
This paper reports the synthesis of host-guest nanocomposite material[Fe(bpy)3]2+Y (where bpy=2,2'-bipyridine) using the flexible ligand method. X-ray diffraction analysis. adsorption technique, and cyclic voltammetry were used to characterize the material. The results show that[Fe(bpy)3]2+ has been entrapped in the supercage of zeolite, its electron transfer is realized by electron hopping of[Fe(bpy)3]2+ within the supercage of zeolite.
This paper reports the synthesis of host-guest nanocomposite material[Fe(bpy)3]2+Y (where bpy=2,2'-bipyridine) using the flexible ligand method. X-ray diffraction analysis. adsorption technique, and cyclic voltammetry were used to characterize the material. The results show that[Fe(bpy)3]2+ has been entrapped in the supercage of zeolite, its electron transfer is realized by electron hopping of[Fe(bpy)3]2+ within the supercage of zeolite.
1999, 10(6): 525-528
Abstract:
8-Hydroxyquinoline. methanol and Triton-100 were first used together in the extraction of metal ions by supercritical CO2, In the new system, the effects of pressure, temperature and the volume of CO2, on the efficiency of supercritical fluid extraction (SFE) were systematically investigated. The recovery under the optimum condition was only 11.38%, but if suitable concentration of methanol (v/v=5%) was added to the supercritical CO2, the recovery was increased significantly (83.60%. RSD=4.37%. n=5). In order to further enhance the recovery Triton X-100 was added to the samples, and the results were satisfactory (96.62%. RSD=2.85%. n=5).
8-Hydroxyquinoline. methanol and Triton-100 were first used together in the extraction of metal ions by supercritical CO2, In the new system, the effects of pressure, temperature and the volume of CO2, on the efficiency of supercritical fluid extraction (SFE) were systematically investigated. The recovery under the optimum condition was only 11.38%, but if suitable concentration of methanol (v/v=5%) was added to the supercritical CO2, the recovery was increased significantly (83.60%. RSD=4.37%. n=5). In order to further enhance the recovery Triton X-100 was added to the samples, and the results were satisfactory (96.62%. RSD=2.85%. n=5).
