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1.
YU Peng  ;LI Xi  ;HU Jun  ;XU Yan-Hua 《结构化学》2014,(9):1375-1382
A novel benzisothiazolin-3-one derivative, 2-(benzo[d]isothiazol-3-yloxy)-N-(3- cyano-l-(4-fluorophenyl)-lH-pyrazol-5-yl) acetamide (8), was synthesized from the initial compound benzo[d]isothiazol-3(2H)-one (BIT) 1 and 4-fluoroaniline 3. The structure of the target compound 8 was determined by elemental analyses, IR and 1H NMR. The single crystals of intermediate compound 6 and the target compound 8 were obtained and determined by X-ray diffraction analysis. The preliminary biological activity was also evaluated and the results showed tile target compound exhibited a good anti-microbial activity.  相似文献   

2.
KAIF4 has been prepared by different procedures and product characterized by XRD and SEM methods.It is indicated that step by step reaction of solution synthesis in which pH = 4 and vaporized at 100℃ was the best procedure for preparing a high purity, thin and particle uniform product.  相似文献   

3.
A simple and effective procedure for the enantioselective synthesis of (R)- and (S)-moprolol was described. The key step was the asymmetric synthesis of enantiopure (R)- and (S)-guaifenesin, which were synthesized from enantioenriched (R)-3-chloro-l,2-propanediol and (S)-epichlorohydrin via kinetics of hydrolysis resolution of racemic epichlorohydrin by chiral Salen-Co^Ⅲ complex. The e.e. values of both the optical compounds were above 98%, and the chemical structures of the target compounds were confirmed by ^1H NMR, ^13C NMR, IR, and MS.  相似文献   

4.
(3S,4R)-Bengamide E(2) was synthesized starting from D-glucono-δ-lactone(3) and the key deoxygenation step from 13 to 15 was achieved by the application of NaBH3CN and ZnI2.Compared with natural bengamide E(1),the synthetic compound(35,4R)-bengamide E(2) was inactive against the cell growth of HUVEC and cancer cells.These data represent the significance of the stereochemistry at C-3 and C-4 of bengamides for structural recognition and binding with the target(s).  相似文献   

5.
The synthesis of racemic cedarmycin B,an antibiotic from Streptomyces sp.TP-A0456 was achieved firstly fromγ- butyrolactone.The key step was a Barbier-type addition of 3-bromomethyl-5H-furan-2-one to formaldehyde mediated by zinc, which afforded the soleγ-addition product 4-hydroxymethyl-3-methylene-dihydrofuran-2-one.The final compound was confirmed by ~1H NMR,~(13)C NMR and HRMS.  相似文献   

6.
A novel diamine 4-[(4'-butoxyphenoxy)carbonyl]phenyl-3",5"-diaminobenzoate (BCDA) was synthesized from 4-butoxyphenol, 4-hydroxybenzoic acid and 3,5-dinitrobenzoic acid through four main intermediates, and a series of polyimides were also synthesized. All the intermediates and the final product were characterized by FTIR and 1H-NMR. The key step in synthesis route is selective hydrolyzation of two ester groups in 4-butoxyphenyl-4'-acetoxybenzoate, by adjusting the reaction temperature and the concentration of ammonia, shorteding the reaction time. The properties of the novel polyimides, such as the aggregation structures, glass transition temperature, solubility and the pretilt angles, were carded out.  相似文献   

7.
The vapor-phase synthesis of 3-methylindole from glycerol and aniline over Cu/NaY modified by K2O was investigated. The catalysts were characterized by X-ray diffraction (XRD) and the temperature- programmed desorption of ammonia (NH3-TPD). The effect of the reaction temperature on the activity and selectivity of Cu]NaY-K2O catalyst was also investigated. The results indicated that the addition of K2O to Cu/NaY increased the selectivity of the catalyst remarkably because the amount of middle-strong acid sites decreased clearly. The decrease of the reaction temperature was beneficial for the increase of 3- methylindole selectivity. Over Cu/NaY-K2O, the selectivity of 3-methylindole reached 75% and the yield of the target product was up to 47% at 220 ℃. A probable catalytic mechanism for the synthesis of 3- methylindole from glycerol and aniline was proposed.  相似文献   

8.
A novel approach to the synthesis of 4-phenylethynylphthalic anhydride has been described.The target compound was synthesized by Pd/Cu catalyzed Sonogashira coupling reaction between phenylacetylene and 4-bromophthalic acid which was for the first time employed as start material,followed by dehydration of 4-phenylethynylphthalic acid.Compared with traditional synthetic routes,this method provides several advantages such as readily available raw materials,convenient manipulation and high yield.The product...  相似文献   

9.
The surface species of CO hydrogenation on CeO2-Co/SiO2 catalyst were investigated using the techniques of temperature programmed reaction and transient response method. The results indicated that the formation of H2O and CO2 was the competitive reaction for the surface oxygen species, CH4 was produced via the hydrogenation of carbon species step by step, and C2 products were formed by the polymerization of surface-active carbon species (-CH2-). Hydrogen assisted the dissociation of CO. The hydrogenation of surface carbon species was the rate-limiting step in the hydrogenation of CO over CeO2-Co/SiO2 catalyst. The investigation of total pressure, gas hourly space velocity (GHSV), and product distribution using nitrogen-rich synthesis gas as feedstock over a laboratory scale fixed-bed reactor indicated that total pressure and GHSV had a significant effect on the catalytic performance of CeO2-Co/SiO2 catalyst. The removal of heat and control of the reaction temperature were extremely critical steps, which required lower GHSV and appropriate CO conversion to avoid the deactivation of the catalyst. The feedstock of nitrogen-rich synthesis gas was favorable to increase the conversion of CO, but there was a shift of product distribution toward the light hydrocarbon. The nitrogen-rich synthesis gas was feasible for F-T synthesis for the utilization of remote natural gas.  相似文献   

10.
Lignin is the most recalcitrant of the three components of lignocellulosic biomass. The strength and stability of the linkages have long been a great challenge for the degradation and valorization of lignin biomass to obtain bio-fuels and commercial chemicals. Up to now, the selective cleavage of C–O linkages of lignin to afford chemicals contains only C, H and O atoms. Our group has developed a cleavage/crosscoupling strategy for converting 4-O-5 linkage lignin model compounds into high value-a...  相似文献   

11.
Lignin is the most recalcitrant of the three components of lignocellulosic biomass. The strength and stability of the linkages have long been a great challenge for the degradation and valorization of lignin biomass to obtain bio-fuels and commercial chemicals. Up to now, the selective cleavage of C–O linkages of lignin to afford chemicals contains only C, H and O atoms. Our group has developed a cleavage/crosscoupling strategy for converting 4-O-5 linkage lignin model compounds into high value-a...  相似文献   

12.
6,8-Dimethoxy-3-[2-(4-methoxyphenyl)ethyl]isocoumarin was synthesized by condensation of 5,7-dimethoxyhompophthalic acid with 3-(4-methoxyphenyl)propanoyl chloride. The structure of the synthesized compound was confirmed by its mass spectrometric studies. The synthesized compound serves as a model for synthesis of DL-agrimonolide.  相似文献   

13.
The synthesis of poly(2-methoxy-5-(2'-ethyl-hexyloxy)-l,4-phenylenevinylene) (MEH-PPV) in the presence of organophilic montmorillonite (OMMT) was reported and the exfoliated MEH-PPV/OMMT nanocomposites was obtained by controlling the ratio of the monomer to the OMMT.  相似文献   

14.
A series of 2-aryl-5-alkyl-7-methoxylbenzo[b]furan derivatives have been synthesized by utilizing the coupling of methyl 3-methoxy-4-hydroxy-5-bromocinnamate with cuprous phenylacetylide as the key step.The structures of the new compounds were confirmed by1H NMR,IR and MS.The structure of compound 14 was further confirmed by single crystal X-ray.Compound 17 showed cytotoxic activity against human lung carcinoma A549.  相似文献   

15.
A compound"vacuum firing and water quenching"technique was presented in the synthesis of LiFePO_4 cathode powder.The sample was prepared by heating the pre-decomposed precursor mixtures sealed in vacuum quartz-tube,followed by water quenching at the sintering temperature.The results indicate that using the"fast quenching"treatment can succeed in controlling overgrowth of the grain size of final product and improving its utilization ratio of active material.The sample synthesized by this technique has the high reversible discharge specific capacity and good cyclic electrochemical performance.  相似文献   

16.
A novel approach to the synthesis of 2,2′,3,3′-biphenyltetracarboxylic dianhydride is described.The target compound was prepared by a nickel-catalyzed coupling reaction of dimethy 3-chlorophthalate(3-DMCP) for 4 h at 70-80℃,followed by subsequent hydrolysis of tetra-ester in acid solution and dehydration of tetra-acid,with overall yield of 68%.The structures of the products were characterized by IR,~1H NMR and ~(13)C NMR respectively.  相似文献   

17.
A novel diamine 4-[(4'-butoxyphenoxy)carbonyl]phenyl-3",5"-diaminobenzoate (BCDA) was synthesized from 4-butoxyphenol, 4-hydroxybenzoic acid and 3,5-dinitrobenzoic acid through four main intermediates, and a series of polyimides were also synthesized. All the intermediates and the final product were characterized by FTIR and 1H-NMR. The key step in synthesis route is selective hydrolyzation of two ester groups in 4-butoxyphenyl-4'-acetoxybenzoate, by adjusting the reaction temperature and the concentration of ammonia, shorteding the reaction time. The properties of the novel polyimides, such as the aggregation structures, glass transition temperature, solubility and the pretilt angles, were carried out.  相似文献   

18.
3-O-[β-D-Glucopyranosyl-(1→3)-α-L-arabinopyranosyl]-oleanolic acid-28-O-[β-D-glucopyranosyl] ester 1 was synthesized concisely by a convergent strategy. Using stepwise fashion for the synthesis of saponin 2, 3-O-{[β-D-glucopyranosyl-(1→2)]-[α-L-arabinopyranosyl-(1→3)]-α-L-arabinopyranosyl)-oleanolic acid-28-O-(β- D-glucopyranosyl) ester, an abnormal phenomenon, that the terminal arabinosyl residue took the ^1C4 conformation instead of typical ^4C1 form, was observed. Deprotection or heating could not resume the normal conformation, which resulted in the product of 2' not 2.  相似文献   

19.
The synthesis of the title molecule was achieved by the reaction of 2,4-dichlorobenzoyl chloride with potassium thiocyanate in 1:1 molar ratio in dry acetonitrile to afford the corresponding isothiocyante in situ followed by the treatment with 2-aminobiphenyl. The structure of the target compound was established by elemental analysis, FTIR, 1H, 13 C NMR and mass spectroscopy and unequivocally confirmed by the crystallographic data. The title compound crystallizes in the monoclinic space group P21/n with a = 13.356(2), b = 7.0761(11), c = 20.539(3) , β = 105.723(4)°, V = 1868.5(5) 3 and Z = 4.  相似文献   

20.
SAEED Aamer 《中国化学》2005,23(6):762-766
A simple synthesis of delphoside, 3-methyl-6-hydroxy-8-O-β-D-glucopyranosyloxy isocoumarin (1), isolated from Delphinium spp. is described. 3,5-Dimethoxyhomophthalic anhydride (2) on treatment with acetyl chloride in the presence of 1,1,3,3-tetramethylguanidine (TMG) and triethyl amine afforded the 6,8-dimethoxy-3-methylisocoumarin (3). Regioselective demethylation of the latter furnished 8-hydroxy-6-methoxy-3-methylisocoumarin (4). Glycosylation with O-(2,3,4,6-tetra-O-acetyl-D-glucopyranosyl)trichloroacetimidate in presence of catalytic amount of boron trifluoride etherate followed by deacetylation using 5% potassium carbonate afforded 3-methyl-6-methoxy-8-O-β-D-glucopyranosyloxyisocoumarin (6) that was finally demethylated to yield delphoside 1.  相似文献   

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