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1996 Volume 7 Issue 2
1996, 7(2): 95-98
Abstract:
Cyclic dithioacetals of α,α-dioxo (ester) ketone 3 were reacted with butanone to afford the Michael adducts 4,catalyzed by metal Na.This process provides a new method for the synthesis of ring-compouds in good yield under mild conditions.
Cyclic dithioacetals of α,α-dioxo (ester) ketone 3 were reacted with butanone to afford the Michael adducts 4,catalyzed by metal Na.This process provides a new method for the synthesis of ring-compouds in good yield under mild conditions.
1996, 7(2): 99-102
Abstract:
A series of aromatic ketones 4-acyl anisole were synthesized with high yield by using carboxylic acids as acylating agents and a HY zeolite as catalyst.
A series of aromatic ketones 4-acyl anisole were synthesized with high yield by using carboxylic acids as acylating agents and a HY zeolite as catalyst.
1996, 7(2): 103-104
Abstract:
The title compound BBBT-DTT (C17H12Br2S5,Mr=536.42) has been synthesized and its structure feature has been described.BBBT-DTT is characterized by one dimensional chains formed by S…S (head to head) and Br…Br (tail to tail) intermiolecular interactions.
The title compound BBBT-DTT (C17H12Br2S5,Mr=536.42) has been synthesized and its structure feature has been described.BBBT-DTT is characterized by one dimensional chains formed by S…S (head to head) and Br…Br (tail to tail) intermiolecular interactions.
1996, 7(2): 105-106
Abstract:
A new approach based on transesterification reaction to synthesizing 2-alkoxycarbonyi-2-methyl ethyl tin trichlorides and their complexes with dibenzylsulfoxide (DBSO) and hexam-ethylphosphoramide (HMPA)was reported.They were characterized by elemental analysis,IR and 1HNMR spectra.The possible mechanism for transesterifications was suggested.
A new approach based on transesterification reaction to synthesizing 2-alkoxycarbonyi-2-methyl ethyl tin trichlorides and their complexes with dibenzylsulfoxide (DBSO) and hexam-ethylphosphoramide (HMPA)was reported.They were characterized by elemental analysis,IR and 1HNMR spectra.The possible mechanism for transesterifications was suggested.
1996, 7(2): 107-108
Abstract:
A novel and efficient convergent synthesis of 13-demethyldeoxofaveline,a Key intermediate for deoxofaveline,faveline and faveline methyl ether,was achieved by Wittig reaction and selective oxidation.And a novel sixteen-membered ring compound has been obtained in the meantime.
A novel and efficient convergent synthesis of 13-demethyldeoxofaveline,a Key intermediate for deoxofaveline,faveline and faveline methyl ether,was achieved by Wittig reaction and selective oxidation.And a novel sixteen-membered ring compound has been obtained in the meantime.
1996, 7(2): 109-110
Abstract:
Starting from geranial a new synthetic route for compound 6,(E,E,E)-3,7-13-trimethyl-6-(i-propenyl)-7,14-dihydroxyl-2,8,12-tetradecatrien-1-methylal,a key intermediate in the synthesis of diterpene epi-mayol is described.
Starting from geranial a new synthetic route for compound 6,(E,E,E)-3,7-13-trimethyl-6-(i-propenyl)-7,14-dihydroxyl-2,8,12-tetradecatrien-1-methylal,a key intermediate in the synthesis of diterpene epi-mayol is described.
1996, 7(2): 111-114
Abstract:
The preparation of a pyrimidone analogue 2 of huperzine A is described,in which the pyridone ring of the natural alkaloid is replaced by pyrimidone.The key intermediate β-ketoester 9 was obtained from cyclohexane-1,4-dione monoethylene ketal via 6 steps.Then using the methodology of total synthesis of huperzine A,the construction of bicyclo[3.3.1]nonane moiety substructure was achieved,and 2 was finally afforded in low yield.
The preparation of a pyrimidone analogue 2 of huperzine A is described,in which the pyridone ring of the natural alkaloid is replaced by pyrimidone.The key intermediate β-ketoester 9 was obtained from cyclohexane-1,4-dione monoethylene ketal via 6 steps.Then using the methodology of total synthesis of huperzine A,the construction of bicyclo[3.3.1]nonane moiety substructure was achieved,and 2 was finally afforded in low yield.
1996, 7(2): 115-118
Abstract:
New tricyclic hydroxycarboxylates-dibenz[b,e]oxepin and dibenzo[b,e]thiepin hydroxycarboxylates (7) were synthesized by modifying the structures of xanthene compounds.The pharmacological results showed the antagonistic activities of these tricyclic compounds were all decreased at different levels after this modification,but they exhibited more selective action on the central nicotinic receptor.Especially,the compounds containing sulfur atom almost have no action on the muscarinic receptors,they were still quite potent to the central nicotinic receptor.
New tricyclic hydroxycarboxylates-dibenz[b,e]oxepin and dibenzo[b,e]thiepin hydroxycarboxylates (7) were synthesized by modifying the structures of xanthene compounds.The pharmacological results showed the antagonistic activities of these tricyclic compounds were all decreased at different levels after this modification,but they exhibited more selective action on the central nicotinic receptor.Especially,the compounds containing sulfur atom almost have no action on the muscarinic receptors,they were still quite potent to the central nicotinic receptor.
1996, 7(2): 119-122
Abstract:
A simple and efficient method for the synthesis of new glycolipids containing oligosaccharide and two long alkyl chains N-[4-(dialkyl-L-glutamatecarbony lethylcarbonylamino)butyl]lactobionamide has been developed in moderate yield.We successfully selected succinic anhydride which could condese with dialkyl L-glutamates in almost quantitative yields.The aminolysis of lactonolactone with 1,4-diaminobutane could be carried out in quantitative yield.The glycolipids prepared by this method have three amino acid residues between hydrophobic segment and hydrophilic moiety of the glycolipid which can be considered to maintain the steric conformation of lipase in enzymatic reactions.
A simple and efficient method for the synthesis of new glycolipids containing oligosaccharide and two long alkyl chains N-[4-(dialkyl-L-glutamatecarbony lethylcarbonylamino)butyl]lactobionamide has been developed in moderate yield.We successfully selected succinic anhydride which could condese with dialkyl L-glutamates in almost quantitative yields.The aminolysis of lactonolactone with 1,4-diaminobutane could be carried out in quantitative yield.The glycolipids prepared by this method have three amino acid residues between hydrophobic segment and hydrophilic moiety of the glycolipid which can be considered to maintain the steric conformation of lipase in enzymatic reactions.
1996, 7(2): 123-126
Abstract:
A polyclonal antibody elicited against hapten (4) catalyzed the hydrolysis of β-naphthol acetate with a rate acceleration of 46400 folds.
A polyclonal antibody elicited against hapten (4) catalyzed the hydrolysis of β-naphthol acetate with a rate acceleration of 46400 folds.
1996, 7(2): 127-128
Abstract:
cis-[Pd(met)(D2O)2]2+ promoted hydrolysis of AcMet-Gly was monitored by 1H NMR spectroscopy.The observed rate constants,koba,strongly depend on the mole ratio of cis-[Pd(met)(D2O)2]2+ to AcMet-Gly.At least,one aqua ligand for each Pd(Ⅱ)is necessary for fast hydrolysis reaction observed.Two aqua ligands of each Pd(Ⅱ) make the reaction faster.
cis-[Pd(met)(D2O)2]2+ promoted hydrolysis of AcMet-Gly was monitored by 1H NMR spectroscopy.The observed rate constants,koba,strongly depend on the mole ratio of cis-[Pd(met)(D2O)2]2+ to AcMet-Gly.At least,one aqua ligand for each Pd(Ⅱ)is necessary for fast hydrolysis reaction observed.Two aqua ligands of each Pd(Ⅱ) make the reaction faster.
1996, 7(2): 129-130
Abstract:
An importment chiral synthon (-)-2,4-dimethyl-1,5-pentanediol and its diester and monoester were obtained by lipase-catalyzed double kinetic resolution.
An importment chiral synthon (-)-2,4-dimethyl-1,5-pentanediol and its diester and monoester were obtained by lipase-catalyzed double kinetic resolution.
1996, 7(2): 131-132
Abstract:
Low pressure column chromatography with activated charcoal powder was used to separate the oligosaccharides and their isomers from the hydrolysates of konjac glucomannan.
Low pressure column chromatography with activated charcoal powder was used to separate the oligosaccharides and their isomers from the hydrolysates of konjac glucomannan.
1996, 7(2): 133-134
Abstract:
Further study on the components of Spiraea japonica var.incisa Yu,resulted in the isolation of a new diterpene spiramilactone,The structure of which was elucidated on the basis of spectral and chemical means.
Further study on the components of Spiraea japonica var.incisa Yu,resulted in the isolation of a new diterpene spiramilactone,The structure of which was elucidated on the basis of spectral and chemical means.
1996, 7(2): 135-138
Abstract:
Three new diterpene alkaloids,transconitine A,B and C were isolated from the roots of Aconitum transsectum Diels,and their structures were elucidated by spectral means.
Three new diterpene alkaloids,transconitine A,B and C were isolated from the roots of Aconitum transsectum Diels,and their structures were elucidated by spectral means.
1996, 7(2): 139-140
Abstract:
A new minor diterpenoid alkaloid contaning a C(19)-N-azomethine group,caerunine (1) was isolated from Delphinium caeruleum Jacq.ex.Cambss,its struture was determined by spectral data.
A new minor diterpenoid alkaloid contaning a C(19)-N-azomethine group,caerunine (1) was isolated from Delphinium caeruleum Jacq.ex.Cambss,its struture was determined by spectral data.
1996, 7(2): 141-144
Abstract:
Two new neolignan glucosides,longiflorosides A and B were isolated from whole plants of Pedicularis longiflora.On the basis of spectral evidence,longiflorosides A and B were determined as (7R,8S)-4-O-methyl-dehydrodiconiferyl alcohol-9'-O-β-D-glucopyranoside and (erythro)-1-(4-O-β-D-glucopyranosyl-3,5-dimethoxy-phenyl)-2-{2-methoxy-4-[1-(E)-propene-3-ol]-phenoxyl}-propane-1,3-diol,respectively.
Two new neolignan glucosides,longiflorosides A and B were isolated from whole plants of Pedicularis longiflora.On the basis of spectral evidence,longiflorosides A and B were determined as (7R,8S)-4-O-methyl-dehydrodiconiferyl alcohol-9'-O-β-D-glucopyranoside and (erythro)-1-(4-O-β-D-glucopyranosyl-3,5-dimethoxy-phenyl)-2-{2-methoxy-4-[1-(E)-propene-3-ol]-phenoxyl}-propane-1,3-diol,respectively.
1996, 7(2): 145-148
Abstract:
Two new neolignan glucosides,tortosides D and E were isolated from plants of Pedicularis toria.On the basis of spectral evidence,tortosides D and E were determined as (7R,8S)-dehydrodiconiferyl-9-O-β-D-4"-O-methyl-glucopyranoside and (7R,8S)-5-methoxy-dihydrodehydrodiconiferyl alcohol-9'-O-β-D-glucopyranoside,respectively.
Two new neolignan glucosides,tortosides D and E were isolated from plants of Pedicularis toria.On the basis of spectral evidence,tortosides D and E were determined as (7R,8S)-dehydrodiconiferyl-9-O-β-D-4"-O-methyl-glucopyranoside and (7R,8S)-5-methoxy-dihydrodehydrodiconiferyl alcohol-9'-O-β-D-glucopyranoside,respectively.
1996, 7(2): 149-152
Abstract:
Further chemical study on Stellaria delavayi led to the isolation of two other new cyclopeptides,namely stelladelin B and C.On the basis of spectroscopic analysis and chemical evidence,their structures were established as cyclo(Gly-Ile-Pro2-Pro1-Ala-Tyr-Asp-Leu) and cylo(Val-Pro3-Tyr2-Pro2-Pro1-Phe-Tyr1-Ser),respectively.
Further chemical study on Stellaria delavayi led to the isolation of two other new cyclopeptides,namely stelladelin B and C.On the basis of spectroscopic analysis and chemical evidence,their structures were established as cyclo(Gly-Ile-Pro2-Pro1-Ala-Tyr-Asp-Leu) and cylo(Val-Pro3-Tyr2-Pro2-Pro1-Phe-Tyr1-Ser),respectively.
1996, 7(2): 153-156
Abstract:
Conformation analysis of the model compounds for tunicamycin V and its natural donor substrate,UDP-N-acetylglucose,is performed to reveal the detail of the inhibition process.
Conformation analysis of the model compounds for tunicamycin V and its natural donor substrate,UDP-N-acetylglucose,is performed to reveal the detail of the inhibition process.
1996, 7(2): 157-158
Abstract:
The geometries of the reactants,the transition states(TS) and the products for the reaction HCO+HNO2→HCHO+NO2 have been optimized by using the energy gradient approach at UHF/6-31G level,and the energies were corrected at the MP2/6-31G level.The calculated barrier(48.15KJ·mol-1) for the reaction is in reasonable agreement with the experimental data (28.84±2.51KJ·mol-1).The Intrinsic Reaction Coordinate (IRC) for the reaction is traced by using Morokuma's magnitude method.The variations of the geometries and the potentials for the reaction system are elucidated along the IRC.
The geometries of the reactants,the transition states(TS) and the products for the reaction HCO+HNO2→HCHO+NO2 have been optimized by using the energy gradient approach at UHF/6-31G level,and the energies were corrected at the MP2/6-31G level.The calculated barrier(48.15KJ·mol-1) for the reaction is in reasonable agreement with the experimental data (28.84±2.51KJ·mol-1).The Intrinsic Reaction Coordinate (IRC) for the reaction is traced by using Morokuma's magnitude method.The variations of the geometries and the potentials for the reaction system are elucidated along the IRC.
1996, 7(2): 159-160
Abstract:
A modified method for the separation of oligosaccharides derivatized with p-aminobenzoate ethyl ester by high performance capillary electrophoresis (HPCE) is described.The isomers of larger oligosaccharides up to 10-mers were separated by HPCE with borax as running buffer.
A modified method for the separation of oligosaccharides derivatized with p-aminobenzoate ethyl ester by high performance capillary electrophoresis (HPCE) is described.The isomers of larger oligosaccharides up to 10-mers were separated by HPCE with borax as running buffer.
1996, 7(2): 161-164
Abstract:
In this paper,the determination of both fluoride and molybdenum can be carried out in the same serum sample as follows:the content of fluoride is determined by direct potentiometry in the solution containing (CH2)6N4 and HNO3 (pH=5.4) while that of molybdenum is determined by adsorptive voltammetry after the above-mentioned solution has been nitrified with mixed acid containing HNO3 and HClO4.
In this paper,the determination of both fluoride and molybdenum can be carried out in the same serum sample as follows:the content of fluoride is determined by direct potentiometry in the solution containing (CH2)6N4 and HNO3 (pH=5.4) while that of molybdenum is determined by adsorptive voltammetry after the above-mentioned solution has been nitrified with mixed acid containing HNO3 and HClO4.
1996, 7(2): 165-166
Abstract:
Surface enhanced Raman spectroscopy (SERS) has been applied to obtain structural information of surface species adsorbed at electrode surface in the electrode potential range of severe hydrogen evolution,which is very difficult to be gained by using most of spectroelectrochemical and conventional electrochemical methods.
Surface enhanced Raman spectroscopy (SERS) has been applied to obtain structural information of surface species adsorbed at electrode surface in the electrode potential range of severe hydrogen evolution,which is very difficult to be gained by using most of spectroelectrochemical and conventional electrochemical methods.
1996, 7(2): 167-168
Abstract:
A new kind of bienzyme maltose sensor was fabricated using molecular deposition technique,in which glucose oxidase and glucoamylase were alternatively deposited with bipolar quaternary ammonium salt on 3-mercapto propionic acid modified gold electrode.Its response performance is described in detail.
A new kind of bienzyme maltose sensor was fabricated using molecular deposition technique,in which glucose oxidase and glucoamylase were alternatively deposited with bipolar quaternary ammonium salt on 3-mercapto propionic acid modified gold electrode.Its response performance is described in detail.
1996, 7(2): 169-172
Abstract:
In this paper,an oscillation frequency equation for a piezoelectric sensor with two separated-electrodes is theoretically derived and experimentally verified.The correlations of the oscillation frequency and the liquid properties are investigated.
In this paper,an oscillation frequency equation for a piezoelectric sensor with two separated-electrodes is theoretically derived and experimentally verified.The correlations of the oscillation frequency and the liquid properties are investigated.
1996, 7(2): 173-176
Abstract:
Aggregation of ethyl p-didecylaminobenzoate (EDOAB) in dioxane-water binary mixture was shown to occur at water volume fraction of 0.47 and a strong intramolecular charge transfer emission was observed in the aggregate.
Aggregation of ethyl p-didecylaminobenzoate (EDOAB) in dioxane-water binary mixture was shown to occur at water volume fraction of 0.47 and a strong intramolecular charge transfer emission was observed in the aggregate.
1996, 7(2): 177-180
Abstract:
This paper reports a complex of sodium chloride with p-nitrophenol,which has not previously been published.The composition and formation constant of the complex have been studied by ion-selective electrode,crystal structure of the complex has been measured.
No complexes were formed for lithium and potassium.
This paper reports a complex of sodium chloride with p-nitrophenol,which has not previously been published.The composition and formation constant of the complex have been studied by ion-selective electrode,crystal structure of the complex has been measured.
No complexes were formed for lithium and potassium.
1996, 7(2): 181-184
Abstract:
Intermolecular Hydrogen Bonding (HB) Patterns in 69 crystal structures of phenols and its simple derivatives were analysed by a non-graphic method automatically.Presented here are the results which are well consistent with the literature reports.
Intermolecular Hydrogen Bonding (HB) Patterns in 69 crystal structures of phenols and its simple derivatives were analysed by a non-graphic method automatically.Presented here are the results which are well consistent with the literature reports.
1996, 7(2): 185-186
Abstract:
The six-coordinate complex [Fe(Ⅱ)(TPP)(NH2Bu1)2] (TPP=mesotetraphenylporphyrinate) has been prepared by i-butylamine reduction method in the existence of antiformin in aerobic solution.The complex was characterized by UV-Vis spectroscopy,IR spectroscopy and elemental analysis.
The six-coordinate complex [Fe(Ⅱ)(TPP)(NH2Bu1)2] (TPP=mesotetraphenylporphyrinate) has been prepared by i-butylamine reduction method in the existence of antiformin in aerobic solution.The complex was characterized by UV-Vis spectroscopy,IR spectroscopy and elemental analysis.
1996, 7(2): 187-188
Abstract:
A new method for preparation of iron(Ⅲ) porphyrin oxyanion complexes was reported.By this method perchlorate complex of iron(Ⅲ) tetraphenylporphyrin [FeTTP(OClO3)] was prepared from i-butylamine complex of iron(Ⅱ) porphyrin [Fe(TPP(NH2Bui)2 by treatment with perchloric acid.
A new method for preparation of iron(Ⅲ) porphyrin oxyanion complexes was reported.By this method perchlorate complex of iron(Ⅲ) tetraphenylporphyrin [FeTTP(OClO3)] was prepared from i-butylamine complex of iron(Ⅱ) porphyrin [Fe(TPP(NH2Bui)2 by treatment with perchloric acid.
1996, 7(2): 189-192
Abstract:
(Tricarbonyl-π-chromiurn)phenylcyclopentadienyl transition metal (Ti,Mo,Mn,Ru,Co) complexes have been synthesized.The crystal structure of (tricarbonyl-π-chromium)phenylcyclopentadienylcobalt dicarbonyl (3) was determined by X-ray diffraction:crystals are orthorhombic.space group P212121,a=15.083(5),b=16.391(5),c=6.351(4) A,V=1570(1) A3 and Z=4.The phenyl ring and the cyclopentadienyl ring in the molecule are not coplanar (dihedral angle:25°).
(Tricarbonyl-π-chromiurn)phenylcyclopentadienyl transition metal (Ti,Mo,Mn,Ru,Co) complexes have been synthesized.The crystal structure of (tricarbonyl-π-chromium)phenylcyclopentadienylcobalt dicarbonyl (3) was determined by X-ray diffraction:crystals are orthorhombic.space group P212121,a=15.083(5),b=16.391(5),c=6.351(4) A,V=1570(1) A3 and Z=4.The phenyl ring and the cyclopentadienyl ring in the molecule are not coplanar (dihedral angle:25°).
1996, 7(2): 193-194
Abstract:
The catalyst Pd/γ-Al2O3 was prepared by modification of γ-AlOOH sol particles with the complex of palladium salt with sol-gel technique in this letter.The pore distribution of the support γ-Al2O3 was very narrow from nitrogen adsorption measurement and the palladium in the γ-Al2O3 was highly dispersed determined from hydrogen chemisorption experiment.
The catalyst Pd/γ-Al2O3 was prepared by modification of γ-AlOOH sol particles with the complex of palladium salt with sol-gel technique in this letter.The pore distribution of the support γ-Al2O3 was very narrow from nitrogen adsorption measurement and the palladium in the γ-Al2O3 was highly dispersed determined from hydrogen chemisorption experiment.
1996, 7(2): 195-198
Abstract:
Thermostability and phase transformation of LiCu2O2,LiCu3O3 and other related copper oxides have been studied by x-ray powder diffraction technique at high temperature in air.Both LiCu2O2 and LiCu3O3 are metastable at room temperature.LiCu2O2 decomposes to Li2CuO2 and a monoclinic phase with CuO structure,while LiCu3O3 transforms to the monoclinic phase at lower temperature.Moreover,evidence for a possible intermediate phase between LiCu3O3 and Li0.25Cu0.75O0.85 has also been presented.
Thermostability and phase transformation of LiCu2O2,LiCu3O3 and other related copper oxides have been studied by x-ray powder diffraction technique at high temperature in air.Both LiCu2O2 and LiCu3O3 are metastable at room temperature.LiCu2O2 decomposes to Li2CuO2 and a monoclinic phase with CuO structure,while LiCu3O3 transforms to the monoclinic phase at lower temperature.Moreover,evidence for a possible intermediate phase between LiCu3O3 and Li0.25Cu0.75O0.85 has also been presented.
1996, 7(2): 199-200
Abstract:
Preparation of P2W15Mo2NbO627- was reported in the paper.It was characterized by elementry analysis,IR,UV,polarography,183W-NMR and XPD spectra.All results showed the structure of the heteropoly anion was the Dawson type.
Preparation of P2W15Mo2NbO627- was reported in the paper.It was characterized by elementry analysis,IR,UV,polarography,183W-NMR and XPD spectra.All results showed the structure of the heteropoly anion was the Dawson type.
1996, 7(2): 201-204
Abstract:
The new crystalline V-Ti-silicalite with mesoporous MCM-41 type molecular sieve structure is synthesized hydrothermally;The framework IR spectra associated with ESR,29Si MAS NMR,DRS and XPS data shows that V and Ti are simultaneously incorporated into V-TiMCM-41 framework.
The new crystalline V-Ti-silicalite with mesoporous MCM-41 type molecular sieve structure is synthesized hydrothermally;The framework IR spectra associated with ESR,29Si MAS NMR,DRS and XPS data shows that V and Ti are simultaneously incorporated into V-TiMCM-41 framework.
