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1995 Volume 6 Issue 9
1995, 6(9): 739-742
Abstract:
We described the synthesis of two S-substituted γ-lactams 1 and 11 by sulfone-based α-amidoalkylation method.This constitutes the formal synthesis of ant venom alkaloids 2 and 3 in racemic form.The key intermediate 18 for the chiral synthesis of 2 and 3 was prepared from new chiral sulfone 7 by the same method.
We described the synthesis of two S-substituted γ-lactams 1 and 11 by sulfone-based α-amidoalkylation method.This constitutes the formal synthesis of ant venom alkaloids 2 and 3 in racemic form.The key intermediate 18 for the chiral synthesis of 2 and 3 was prepared from new chiral sulfone 7 by the same method.
1995, 6(9): 743-744
Abstract:
The rearrangement of as-triazolium salt (1) to 5-amino-1(2, 4-dichloro)benzyl-4-(2, 2-dimethyl) propionylimidazole (2) with NaH in dimethylformamide(DMF) is described.
The rearrangement of as-triazolium salt (1) to 5-amino-1(2, 4-dichloro)benzyl-4-(2, 2-dimethyl) propionylimidazole (2) with NaH in dimethylformamide(DMF) is described.
1995, 6(9): 745-746
Abstract:
The substituted nitroarenes were reduced effectively to the corresponding aniline derivatives by an insoluble resin with viologen structure as an electron-transfer catalyst (ETC) in dichloromelhane-resin-water three-phase system.
The substituted nitroarenes were reduced effectively to the corresponding aniline derivatives by an insoluble resin with viologen structure as an electron-transfer catalyst (ETC) in dichloromelhane-resin-water three-phase system.
1995, 6(9): 747-750
Abstract:
The 1E, 3E-dienyldiethyl phosphoniate and 1E, 3E-dienyldiphenyl phoephine oxide were synthesized via isomerization of alkynyldiethyl phosphonate and alkynydiphenyl phosphine oxide effected by tributyl-phosphine.
The 1E, 3E-dienyldiethyl phosphoniate and 1E, 3E-dienyldiphenyl phoephine oxide were synthesized via isomerization of alkynyldiethyl phosphonate and alkynydiphenyl phosphine oxide effected by tributyl-phosphine.
1995, 6(9): 751-752
Abstract:
In the presence of potassium t-butoxide, N, N-dimethylamino thiocarbonyl thiomethyl triphenylphosphonium bromide formed the corresponding ylide in situ, which can undergo Wittig reaction with aldehydes to give vinyl dithiocarbamates in high yields.If the esters were hydrolyzed with ethanol aqueous sodium hydroxide, a new method to lengthen aldehydes by one carbon atom was a-complished.
In the presence of potassium t-butoxide, N, N-dimethylamino thiocarbonyl thiomethyl triphenylphosphonium bromide formed the corresponding ylide in situ, which can undergo Wittig reaction with aldehydes to give vinyl dithiocarbamates in high yields.If the esters were hydrolyzed with ethanol aqueous sodium hydroxide, a new method to lengthen aldehydes by one carbon atom was a-complished.
1995, 6(9): 753-754
Abstract:
A concise route to a trachylobagibberellin analogue-dimethyl ester of 3-hydroxy-△1,10-12, 16-cyclogibberellin 12 was reported in this paper, starting from GA3 in eight steps.
A concise route to a trachylobagibberellin analogue-dimethyl ester of 3-hydroxy-△1,10-12, 16-cyclogibberellin 12 was reported in this paper, starting from GA3 in eight steps.
1995, 6(9): 755-758
Abstract:
Several potential insecticides were synthesized by incorporating chrysanthemic acid and O, O-dialkyl phosphoro-dithioate through a pyrrolindine-2, 5-dione group.Their structures were determined by elementary analysis, NMR, IR and MS.
Several potential insecticides were synthesized by incorporating chrysanthemic acid and O, O-dialkyl phosphoro-dithioate through a pyrrolindine-2, 5-dione group.Their structures were determined by elementary analysis, NMR, IR and MS.
1995, 6(9): 759-762
Abstract:
The synthesis of eight enantiomers of ohmefentanyl isothiocyanate and the determination of their absolute configuration were described.
The synthesis of eight enantiomers of ohmefentanyl isothiocyanate and the determination of their absolute configuration were described.
1995, 6(9): 763-764
Abstract:
The synthesis of isothiocyanate derivatives of carfentanil and 4-methoxymethyl-fentanyl was described.
The synthesis of isothiocyanate derivatives of carfentanil and 4-methoxymethyl-fentanyl was described.
1995, 6(9): 765-768
Abstract:
The synthesis of 2-furancarboxamide, 2-thiophenecarboxamide and 2-tetrahydro-furancarboxamide analogues of SuperFIT, CarFIT and MethoFIT was described.
The synthesis of 2-furancarboxamide, 2-thiophenecarboxamide and 2-tetrahydro-furancarboxamide analogues of SuperFIT, CarFIT and MethoFIT was described.
1995, 6(9): 769-770
Abstract:
The phenylseleno substituted aromatic compounds were prepared via the Diels-Alder reaction of phenylseleno substituted dienes with dimethyl acetyienedicarboxylate followed by DDQ dehydrogenation.
The phenylseleno substituted aromatic compounds were prepared via the Diels-Alder reaction of phenylseleno substituted dienes with dimethyl acetyienedicarboxylate followed by DDQ dehydrogenation.
1995, 6(9): 771-772
Abstract:
The designed and synthesized compounds are the coordination compounds between MCl2(M=Cu, Co, Mn) and the Mannich base made by methyl piperizine and tetracycline hydrochloride.The cancer cells of HCT-8, KB, A2780, MGC80-1 and Bel7402 are significantly inhibited by the drugs in vitro.The inhibition ratio of S-180 tumor by the compound of M=Cu is 30% on 10mg/kg level of feed from the in vivo experiments of female white mice.
The designed and synthesized compounds are the coordination compounds between MCl2(M=Cu, Co, Mn) and the Mannich base made by methyl piperizine and tetracycline hydrochloride.The cancer cells of HCT-8, KB, A2780, MGC80-1 and Bel7402 are significantly inhibited by the drugs in vitro.The inhibition ratio of S-180 tumor by the compound of M=Cu is 30% on 10mg/kg level of feed from the in vivo experiments of female white mice.
1995, 6(9): 772-774
Abstract:
Hydrogenation of fullerene catalyzed by palladium was studied.FD-Ms spectrum exhibited that C60H12 and C60H20, among the mixture of adducts C60H2n (n=1 to 26) were the main products.The mechanism for the hydrogenation of fullerene under our conditions is described.
Hydrogenation of fullerene catalyzed by palladium was studied.FD-Ms spectrum exhibited that C60H12 and C60H20, among the mixture of adducts C60H2n (n=1 to 26) were the main products.The mechanism for the hydrogenation of fullerene under our conditions is described.
1995, 6(9): 775-778
Abstract:
Two new polyhydroxy heptene derivatives, named microcarpin A and microcarpin B, were isolated from Uvaria microcarpa Champ ex Benth.Their structures were determined by the means of spectroscopy and chemistry.
Two new polyhydroxy heptene derivatives, named microcarpin A and microcarpin B, were isolated from Uvaria microcarpa Champ ex Benth.Their structures were determined by the means of spectroscopy and chemistry.
1995, 6(9): 779-782
Abstract:
A new iridoid, lamiophlomiside, was isolated from the root of Lamiophlomis rotata and its structure was elucidated mainly on the basis of spectroscopic data for the glucoside itself and its bis-benzylidene derivatives.
A new iridoid, lamiophlomiside, was isolated from the root of Lamiophlomis rotata and its structure was elucidated mainly on the basis of spectroscopic data for the glucoside itself and its bis-benzylidene derivatives.
1995, 6(9): 783-786
Abstract:
Histidine was determined at the 5.0×10-6-1.0×10-6mol/L level by differential pulse adsorptive cathodic stripping voltammetry at a hanging mercury drop electrode using the reduction peak of its nickel(Ⅱ) complex at-1.16v(vs.Ag/AgCl) obtained in pH-10.2 borate buffer solution.Other amino acids do not interfere.This method has been used for the direct determination of histidine in serum.
Histidine was determined at the 5.0×10-6-1.0×10-6mol/L level by differential pulse adsorptive cathodic stripping voltammetry at a hanging mercury drop electrode using the reduction peak of its nickel(Ⅱ) complex at-1.16v(vs.Ag/AgCl) obtained in pH-10.2 borate buffer solution.Other amino acids do not interfere.This method has been used for the direct determination of histidine in serum.
1995, 6(9): 787-788
Abstract:
A new triazene reagent 1-(2-benzothiazolyl)-3-(4-phenylazophenyl)-triazene (BTPAPT) has been synthesized.The colour reaction of BTPAPT with Cd (Ⅱ) has been studied.At pH=9~11, in the presence of Triton X-100, the reagent with Cd (Ⅱ) forms a complex with high sensitivity, the molar ratio of Cd (Ⅱ) to BTPAPT is 1:2.The molar absorptivity is 1.4×105L·mol-1·cm-1, Beer's law is obeyed for Cd (Ⅱ) in the range of 0-14μg/25ml.
A new triazene reagent 1-(2-benzothiazolyl)-3-(4-phenylazophenyl)-triazene (BTPAPT) has been synthesized.The colour reaction of BTPAPT with Cd (Ⅱ) has been studied.At pH=9~11, in the presence of Triton X-100, the reagent with Cd (Ⅱ) forms a complex with high sensitivity, the molar ratio of Cd (Ⅱ) to BTPAPT is 1:2.The molar absorptivity is 1.4×105L·mol-1·cm-1, Beer's law is obeyed for Cd (Ⅱ) in the range of 0-14μg/25ml.
1995, 6(9): 789-790
Abstract:
A new method of micelle-sensitized derivative variable-angle synchronous spectrofluorometry has been developed for the simultaneous determination of 2, 2'-dihydroxybiphenyl (DHP) and hydroxybiphenyl (HP).The locations of variable-angle synchronous fluorescence peaks for DHP and HP coincide with those of excitation and emission peaks in routine spectra.The spectral interference of analyte can be overcome by derivative technique.The method is rapid and sensitive.
A new method of micelle-sensitized derivative variable-angle synchronous spectrofluorometry has been developed for the simultaneous determination of 2, 2'-dihydroxybiphenyl (DHP) and hydroxybiphenyl (HP).The locations of variable-angle synchronous fluorescence peaks for DHP and HP coincide with those of excitation and emission peaks in routine spectra.The spectral interference of analyte can be overcome by derivative technique.The method is rapid and sensitive.
1995, 6(9): 791-794
Abstract:
A stream-lined assay has beem developed for the determination of monosaccharides and oligosaccharides (free sugars), starch, soluble and insoluble non-starch polysaccharides of cereals and cereal products on a one-sample basis.After extraction of the free sugars with 80% ethanol, the sample is extracted in acetate buffer(pH 5.0)with highy specific α-amylase and amyloglucosidase to degrade the starch, at the same time the non-starch polysaccharides (NSP) are fractioned into soluble and insoluble fractions.An aliquot from the supernatant containing the glucose released from starch is taken and analysed for starch using a glucose-oxidase/peroxidase method.The free sugars, soluble and insoluble NSP are then hydrolysed with acids and the released monosaccharides are reduced and acetylated.The resulting alditol acetates are accurately quantified using GC fitted with a capillary column in addition to accurately quantifying each of the monosaccharide constituents of the NSP, the procedure also gives accurate values for starch and free sugars.
A stream-lined assay has beem developed for the determination of monosaccharides and oligosaccharides (free sugars), starch, soluble and insoluble non-starch polysaccharides of cereals and cereal products on a one-sample basis.After extraction of the free sugars with 80% ethanol, the sample is extracted in acetate buffer(pH 5.0)with highy specific α-amylase and amyloglucosidase to degrade the starch, at the same time the non-starch polysaccharides (NSP) are fractioned into soluble and insoluble fractions.An aliquot from the supernatant containing the glucose released from starch is taken and analysed for starch using a glucose-oxidase/peroxidase method.The free sugars, soluble and insoluble NSP are then hydrolysed with acids and the released monosaccharides are reduced and acetylated.The resulting alditol acetates are accurately quantified using GC fitted with a capillary column in addition to accurately quantifying each of the monosaccharide constituents of the NSP, the procedure also gives accurate values for starch and free sugars.
1995, 6(9): 795-796
Abstract:
Transient photocurrents induced by short light pulses at lattice-matched GaAs/AlxGa1-xAs multiple quantum well (MQW) electrodes were studied as a function of elelctrode potential.Dual exponential photocurrent decay transients were observed at various potentials.By analysis of the dual exponential decay transients, information on steady state photocurrents (IS), surface collection of photoexcited minority carriers (G0) and lifetimes of surface states (TS) was obtained.The kinetic behaviors of photoprocesses at illuminated MQW/electrolyte interface were discussed.
Transient photocurrents induced by short light pulses at lattice-matched GaAs/AlxGa1-xAs multiple quantum well (MQW) electrodes were studied as a function of elelctrode potential.Dual exponential photocurrent decay transients were observed at various potentials.By analysis of the dual exponential decay transients, information on steady state photocurrents (IS), surface collection of photoexcited minority carriers (G0) and lifetimes of surface states (TS) was obtained.The kinetic behaviors of photoprocesses at illuminated MQW/electrolyte interface were discussed.
1995, 6(9): 797-800
Abstract:
AMI MO method has been used to study the thermal decomposition of CF3C(O)O2NO2, CClF2C(O)O2NO2 CCl2FC(O)O2NO2 and CCl3C(O)O2NO2.The results obtained show that the thermolyses of these compounds are unimolecular decomposotion reactions.
AMI MO method has been used to study the thermal decomposition of CF3C(O)O2NO2, CClF2C(O)O2NO2 CCl2FC(O)O2NO2 and CCl3C(O)O2NO2.The results obtained show that the thermolyses of these compounds are unimolecular decomposotion reactions.
1995, 6(9): 801-804
Abstract:
The stability constants of ternary complexes of the type Zn(ATP)L2-, where L=pyridine, 4-picoline, 3, 4-lutidine and 3, 5-lutidine, have been determined by potentiometric pH titration in aqueous solution and compared with the stability of the corresponding binary complexes ZnL2+.It has been observed that there is a stacking interaction between the pyridine ring of the pyridine-like ligands and the purine moiety of ATP in the ternary Zn(ATP)L2- complexes and this stacking interaction is stronger than that in corresponding Co (ATP) L2- complexes.
The stability constants of ternary complexes of the type Zn(ATP)L2-, where L=pyridine, 4-picoline, 3, 4-lutidine and 3, 5-lutidine, have been determined by potentiometric pH titration in aqueous solution and compared with the stability of the corresponding binary complexes ZnL2+.It has been observed that there is a stacking interaction between the pyridine ring of the pyridine-like ligands and the purine moiety of ATP in the ternary Zn(ATP)L2- complexes and this stacking interaction is stronger than that in corresponding Co (ATP) L2- complexes.
1995, 6(9): 805-806
Abstract:
A new method based on transesterification reactions for synthesizing 2-alkoxycar-bonylethyltin trichlorides(1) and their dimethylsulfoxide complexes (2) was reported.1 and 2 were characterized by elemental analysis, IR and 1HNMR spectra.The possible mechanism for their trans esterifications was suggested.
A new method based on transesterification reactions for synthesizing 2-alkoxycar-bonylethyltin trichlorides(1) and their dimethylsulfoxide complexes (2) was reported.1 and 2 were characterized by elemental analysis, IR and 1HNMR spectra.The possible mechanism for their trans esterifications was suggested.
1995, 6(9): 807-810
Abstract:
The preparation and characterization of novel electrocataiyst for oxygen reduction have been carried out.It is found that heated Fe-PPy/C catalysts show good catalytic activity for oxygen reduction in alkaline or acid solutions.Direct correlation between ESR signal and catalytic activity of the catalysts has been obtained.Some implications from this catalytic system have also been discussed.
The preparation and characterization of novel electrocataiyst for oxygen reduction have been carried out.It is found that heated Fe-PPy/C catalysts show good catalytic activity for oxygen reduction in alkaline or acid solutions.Direct correlation between ESR signal and catalytic activity of the catalysts has been obtained.Some implications from this catalytic system have also been discussed.
1995, 6(9): 811-814
Abstract:
KF/Al2O3 reached maximum activity at the pretreatment temperature(Tp) of 623K or 723K in 1-butene isomerization at 273K, according to the amount of KF loaded.Further increment of Tp lowered the activity of KF/Al2O3 due to the suppression of[Al-OH-F]strong basic sites through dehydroxylation.Changes in the state and function of F- caused the deactivation of KF/Al2O3 at high Tp.
KF/Al2O3 reached maximum activity at the pretreatment temperature(Tp) of 623K or 723K in 1-butene isomerization at 273K, according to the amount of KF loaded.Further increment of Tp lowered the activity of KF/Al2O3 due to the suppression of[Al-OH-F]strong basic sites through dehydroxylation.Changes in the state and function of F- caused the deactivation of KF/Al2O3 at high Tp.
1995, 6(9): 815-818
Abstract:
Preadsorption of H2O promotes CO2 adsorption on KF or KF/CaF2, and provokes appearance of bicarbonates on KF/Al2O3.The existence of partially hydrated fluoride species was confirmed, but they were not the main active sites for 1-butene isomerization.Oxygen element is proved to be necessary in carrier to create strong basic sites through the interaction between dispersed KF and support.
Preadsorption of H2O promotes CO2 adsorption on KF or KF/CaF2, and provokes appearance of bicarbonates on KF/Al2O3.The existence of partially hydrated fluoride species was confirmed, but they were not the main active sites for 1-butene isomerization.Oxygen element is proved to be necessary in carrier to create strong basic sites through the interaction between dispersed KF and support.
1995, 6(9): 819-822
Abstract:
Tungsten nitride supported over activated carbon has been used as the catalyst for pyridine hydrodenitrogenation(HDN) for the first time.It has been found that W2N/C has high catalytic activity and selectivity for HDN.
Tungsten nitride supported over activated carbon has been used as the catalyst for pyridine hydrodenitrogenation(HDN) for the first time.It has been found that W2N/C has high catalytic activity and selectivity for HDN.
1995, 6(9): 823-836
Abstract:
Six novel peroxo complexes of rare earth metals containing 1, 10-phen as a coligand Re2H2O2phen2Cl5·nC2H5OH (n=0.5 for La, Nd;n=1 for Sm, Gd, Dy, Y)have been prepared.They were characterized by elemental analysis, IR, TG-DTA and X-ray powder diffraction.
Six novel peroxo complexes of rare earth metals containing 1, 10-phen as a coligand Re2H2O2phen2Cl5·nC2H5OH (n=0.5 for La, Nd;n=1 for Sm, Gd, Dy, Y)have been prepared.They were characterized by elemental analysis, IR, TG-DTA and X-ray powder diffraction.
1995, 6(9): 827-830
Abstract:
The oxygen-deficient magnetite (Fe3O4-δ, (δ>0) was obtained by the reduction of Fe3O4+δ)(δ>0) with CO and the decomposition reactivity of H2O was studied on Fe3O4-δ, (δ>0).The results showed that H2O was reduced to H2 at 563K.The larger the oxygen-deficiency of magnetite, the higher the decomposition activity of H2O.
The oxygen-deficient magnetite (Fe3O4-δ, (δ>0) was obtained by the reduction of Fe3O4+δ)(δ>0) with CO and the decomposition reactivity of H2O was studied on Fe3O4-δ, (δ>0).The results showed that H2O was reduced to H2 at 563K.The larger the oxygen-deficiency of magnetite, the higher the decomposition activity of H2O.
1995, 6(9): 831-832
Abstract:
a novel three dimensional network complex polymer, namely, GdFe(CN)3)·4H2O, has been synthesized from a water solution of gadollinium chloride and potassium ferricyanide.The complex crystallized in the monoclinic system, space group c2, with a=12.759(6), b=7.404(1), c=13.654(5)A, s=4, β=90.22(3), Mr=441.33, Dc=2.28g/cm2, μ(Mo K∞))=38.36cm-1, F(000)=832, R=0.065 for 1048 independent observed reflections.The coordinated environment of Fe(Ⅲ) ion and Gd(Ⅲ) ion are distorted octahedron and 4-capped trigonal prism, respectively.The variable-temperature magnetic susceptibility of the complex was measured over 4.2-300K, giving the exchange integral 2J=-138.2cm-1 and indicating that a mediate antiferromagnetic spin-exchange interaction between the Fe (Ⅲ) ions and the Gd(Ⅲ) ions within each binuclear unit.
a novel three dimensional network complex polymer, namely, GdFe(CN)3)·4H2O, has been synthesized from a water solution of gadollinium chloride and potassium ferricyanide.The complex crystallized in the monoclinic system, space group c2, with a=12.759(6), b=7.404(1), c=13.654(5)A, s=4, β=90.22(3), Mr=441.33, Dc=2.28g/cm2, μ(Mo K∞))=38.36cm-1, F(000)=832, R=0.065 for 1048 independent observed reflections.The coordinated environment of Fe(Ⅲ) ion and Gd(Ⅲ) ion are distorted octahedron and 4-capped trigonal prism, respectively.The variable-temperature magnetic susceptibility of the complex was measured over 4.2-300K, giving the exchange integral 2J=-138.2cm-1 and indicating that a mediate antiferromagnetic spin-exchange interaction between the Fe (Ⅲ) ions and the Gd(Ⅲ) ions within each binuclear unit.
