Photolysis rate (J1) and reaction rate constants (kl) for the biacetyl (butane-2,3-dione) were evaluated in aqueous phase using a continuous photolysis system with a conventional Xe-Hg arc lamp as a light source...Photolysis rate (J1) and reaction rate constants (kl) for the biacetyl (butane-2,3-dione) were evaluated in aqueous phase using a continuous photolysis system with a conventional Xe-Hg arc lamp as a light source. The OH radicals was generated by H2OE/UV process and biacetyl (CH3C(O)C(O)CH3) concentrations were monitored using 2,4-DNPH derivatization method. 2,3-butanedione molecule is widely present in the atmosphere, it have been detected in hydrometeors (fogs, rain, and clouds) and at a significant yield (up to 10μmolar). The measurements were performed at 294 K and with free pH values. Our results lead to the following obtained values: J1= 3×10^-4 S^-1 and k1 = (6.17±0.95)×10^8 M^-1·s^-1.The uncertainty listed above is ±15%.展开更多
Some more new sulfur compounds bearing heterocyclic systems mainly 2-thioxo-1,3,4-thiadiazinone derivatives 2-7 and 3-thioxo-1,2,4-triazole derivatives 9 have been synthetic via alkylation, acylation and condensation ...Some more new sulfur compounds bearing heterocyclic systems mainly 2-thioxo-1,3,4-thiadiazinone derivatives 2-7 and 3-thioxo-1,2,4-triazole derivatives 9 have been synthetic via alkylation, acylation and condensation of dithioic formic acid hydrazide 1 through ring closure reactions with α,β-bi functional groups compounds. Most of the obtained target showed a highly activity towards some microbial in compare with two references antibiotics, Pipercillin and Mycostatine. The structures of the products have been established from their elemental and spectral analysis.展开更多
Some new 2-thioxo thiazole, 2-thioxo 1,3,4- thiadiazole and 3-thioxo-1,3,4-triazole derivatives (3-17) have been synthesized through ring closure reactions ofdithioic formic acid hydrazones 2 with functional reagent...Some new 2-thioxo thiazole, 2-thioxo 1,3,4- thiadiazole and 3-thioxo-1,3,4-triazole derivatives (3-17) have been synthesized through ring closure reactions ofdithioic formic acid hydrazones 2 with functional reagents in different medium. Former structures of the products have been established by the help of elemental and spectral analysis. Most of the obtained targets showed a moderate activity towards some microbes in comparison with two antibiotics Pipercillin and Mycostatine.展开更多
Cyclodextrins have gained wide attentions for their unique physicochemicai properties. In recent years, conducting polymers with special micro-structure and properties are synthesized in the presence of cyclodextrins....Cyclodextrins have gained wide attentions for their unique physicochemicai properties. In recent years, conducting polymers with special micro-structure and properties are synthesized in the presence of cyclodextrins. In this article, the application of cyclodextrins in the synthesis process of conducting polymer metarials is discussed. And authors' study results are summarized.展开更多
Diisopropylidenated α-D-glucofuranose (1) was oxidated with CrO3-pyridine complex. Oxidated product and its hydrate were separated and were reduced together to synthesize diisopropylidenated α-D-allofuranose ( 3...Diisopropylidenated α-D-glucofuranose (1) was oxidated with CrO3-pyridine complex. Oxidated product and its hydrate were separated and were reduced together to synthesize diisopropylidenated α-D-allofuranose ( 3). The yield of 3 increased by 8% than that with only oxidated product as reduction substrate. Benzoylated derivative of 3 was selectively nydrolyzed and dimesylated to synthesize 3-O-benzoyl-1 .2- O- isopropylidene-α-D-allofuranose ( 5 ) and its dimesylated derivative respectively. The overall yield of 5 from 1 was 36%. Each step and final products were analyzed by ^1H-NMR spectra and other methods. The experiments showed that the influence of acetic acid concentration on selective hydrolysis was obvious. The hydrolysis yield was 81.8%. Oxidation. reduction and other procedures were practical and had application potential.展开更多
An adenine nucleotide derivative 2-aminoadenosine 5'-triphosphate was chemically synthesized through four steps and was characterized with 1H NMR, 31p NMR, 13C NMR, EA and FT-IR. Its ultraviolet and fluorescence prop...An adenine nucleotide derivative 2-aminoadenosine 5'-triphosphate was chemically synthesized through four steps and was characterized with 1H NMR, 31p NMR, 13C NMR, EA and FT-IR. Its ultraviolet and fluorescence properties at various pH values were studied. Two pKa values for the compound were determined by the curves of UV absorption dependency on pH, Which were 0.68 and 4.83, respectively. The values were consistent with those calculated from ACD/Labs software. In addition, hydrolysis of the adenine nucleotide derivative in the catalysis of potato apyrase was studied. The competition of the ATP analogue with ATP for potato apyrase' active site was proved to be a sequential reaction mechanism.展开更多
The first successful attempt to prepare W_3S_4 {S_2P (OEt )_2}_4(H_2O) in organic phase is reported. Its substitution and addition reactions are investigated systematically, and the substitution sequences of the '...The first successful attempt to prepare W_3S_4 {S_2P (OEt )_2}_4(H_2O) in organic phase is reported. Its substitution and addition reactions are investigated systematically, and the substitution sequences of the 'loose' ligands are determined. The crystallographic data of the cluster compounds with [W_3S_4] ̄(4+) and [W_3CuS_4] ̄(5+) cores are compared and their UV-Vis spectra are firstly reported. Thus, the 'quasi-aromaticity' of the [W_3S_4] ̄(4+) core of these cluster compounds is discussed.展开更多
The cationic reagent 1-(3-aminopropyl)-3-butylimidazolium bromide(BAPI) was exploited for the derivatization of carboxyl groups on peptides.Nearly 100% derivatization efficiency was achieved with the synthetic peptide...The cationic reagent 1-(3-aminopropyl)-3-butylimidazolium bromide(BAPI) was exploited for the derivatization of carboxyl groups on peptides.Nearly 100% derivatization efficiency was achieved with the synthetic peptide RVYVHPI(RI-7).Furthermore,the peptide derivative was stable in a 0.1% TFA/water solution or a 0.1%(v/v) TFA/acetonitrile/water solution for at least one week.The effect of BAPI derivatization on the ionization of the peptide RI-7 was further investigated,and the detection sensitivity was improved >42-fold via matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF MS),thus outperforming the commercial piperazine derivatization approach.Moreover,the charge states of the peptide were largely increased via BAPI derivatization by electrospray ionization(ESI) MS.The results indicate the potential merits of BAPI derivatization for high sensitivity peptide analysis by MS.展开更多
An inexpensive BF3·Et20-catalyzed annulation reaction of arylacetaldehydes with arylalkynes has been developed. Various substituted phenylacetaldehydes and phenylacetylenes can undergo this reaction, producing co...An inexpensive BF3·Et20-catalyzed annulation reaction of arylacetaldehydes with arylalkynes has been developed. Various substituted phenylacetaldehydes and phenylacetylenes can undergo this reaction, producing corresponding α-aryl substituted naphthalene derivatives. Use of inexpensive and readily available BF3·Et20 catalyst constitutes the most attractive advantage of this transformation.展开更多
Both 1,5-benzodiazepine and quinoxaline derivatives are important heterocycles in pharmaceuticals. We describe an efficient and clean method for the synthesis of 1,5-benzodiazepines from o-phenylenediamine and ketones...Both 1,5-benzodiazepine and quinoxaline derivatives are important heterocycles in pharmaceuticals. We describe an efficient and clean method for the synthesis of 1,5-benzodiazepines from o-phenylenediamine and ketones catalyzed by sodium tetrachloroaurate(Ⅲ) dihydrate under mild conditions. The catalyst was shown to be equally effective for the synthesis of quinoxalines from o-phenylenediamine and α-bromo ketones under the similar reaction conditions. This method produced good yields.展开更多
Caffeine is one of methyl xanthine compounds,which has the similar mode of action as ryanodine receptor insecticide.In order to find novel and efficient insecticide,structural modification of certain methyl xanthine c...Caffeine is one of methyl xanthine compounds,which has the similar mode of action as ryanodine receptor insecticide.In order to find novel and efficient insecticide,structural modification of certain methyl xanthine compounds was made by introducing some common pesticidal active moieties into the structure of caffeine.Eleven novel methyl xanthine compounds were synthesized and characterized by 1H nuclear magnetic resonance(1H NMR),elemental analylsis or high-resolution mass spectrometry(HRMS).According to the biological activity results,it was found that these new compounds show moderate activity towards Mythimna separata Walker and Culex pipiens pallens.For example,compound 2d shows a lethality rate of 40% at 200 mg/L towards Mythimna separata Walker,compounds 2i and 2f show 56.7% and 53.3% lethality rates at 2 mg/L towards Culex pipiens pallens,which are all better than caffeine.In addition,some compounds of them show moderate antifungal activity to some plant pathogenous fungi.展开更多
文摘Photolysis rate (J1) and reaction rate constants (kl) for the biacetyl (butane-2,3-dione) were evaluated in aqueous phase using a continuous photolysis system with a conventional Xe-Hg arc lamp as a light source. The OH radicals was generated by H2OE/UV process and biacetyl (CH3C(O)C(O)CH3) concentrations were monitored using 2,4-DNPH derivatization method. 2,3-butanedione molecule is widely present in the atmosphere, it have been detected in hydrometeors (fogs, rain, and clouds) and at a significant yield (up to 10μmolar). The measurements were performed at 294 K and with free pH values. Our results lead to the following obtained values: J1= 3×10^-4 S^-1 and k1 = (6.17±0.95)×10^8 M^-1·s^-1.The uncertainty listed above is ±15%.
文摘Some more new sulfur compounds bearing heterocyclic systems mainly 2-thioxo-1,3,4-thiadiazinone derivatives 2-7 and 3-thioxo-1,2,4-triazole derivatives 9 have been synthetic via alkylation, acylation and condensation of dithioic formic acid hydrazide 1 through ring closure reactions with α,β-bi functional groups compounds. Most of the obtained target showed a highly activity towards some microbial in compare with two references antibiotics, Pipercillin and Mycostatine. The structures of the products have been established from their elemental and spectral analysis.
文摘Some new 2-thioxo thiazole, 2-thioxo 1,3,4- thiadiazole and 3-thioxo-1,3,4-triazole derivatives (3-17) have been synthesized through ring closure reactions ofdithioic formic acid hydrazones 2 with functional reagents in different medium. Former structures of the products have been established by the help of elemental and spectral analysis. Most of the obtained targets showed a moderate activity towards some microbes in comparison with two antibiotics Pipercillin and Mycostatine.
文摘Cyclodextrins have gained wide attentions for their unique physicochemicai properties. In recent years, conducting polymers with special micro-structure and properties are synthesized in the presence of cyclodextrins. In this article, the application of cyclodextrins in the synthesis process of conducting polymer metarials is discussed. And authors' study results are summarized.
基金Supported by Tianjin Natural Science Foundation ( No. 05YFJMJC09600).
文摘Diisopropylidenated α-D-glucofuranose (1) was oxidated with CrO3-pyridine complex. Oxidated product and its hydrate were separated and were reduced together to synthesize diisopropylidenated α-D-allofuranose ( 3). The yield of 3 increased by 8% than that with only oxidated product as reduction substrate. Benzoylated derivative of 3 was selectively nydrolyzed and dimesylated to synthesize 3-O-benzoyl-1 .2- O- isopropylidene-α-D-allofuranose ( 5 ) and its dimesylated derivative respectively. The overall yield of 5 from 1 was 36%. Each step and final products were analyzed by ^1H-NMR spectra and other methods. The experiments showed that the influence of acetic acid concentration on selective hydrolysis was obvious. The hydrolysis yield was 81.8%. Oxidation. reduction and other procedures were practical and had application potential.
文摘An adenine nucleotide derivative 2-aminoadenosine 5'-triphosphate was chemically synthesized through four steps and was characterized with 1H NMR, 31p NMR, 13C NMR, EA and FT-IR. Its ultraviolet and fluorescence properties at various pH values were studied. Two pKa values for the compound were determined by the curves of UV absorption dependency on pH, Which were 0.68 and 4.83, respectively. The values were consistent with those calculated from ACD/Labs software. In addition, hydrolysis of the adenine nucleotide derivative in the catalysis of potato apyrase was studied. The competition of the ATP analogue with ATP for potato apyrase' active site was proved to be a sequential reaction mechanism.
文摘The first successful attempt to prepare W_3S_4 {S_2P (OEt )_2}_4(H_2O) in organic phase is reported. Its substitution and addition reactions are investigated systematically, and the substitution sequences of the 'loose' ligands are determined. The crystallographic data of the cluster compounds with [W_3S_4] ̄(4+) and [W_3CuS_4] ̄(5+) cores are compared and their UV-Vis spectra are firstly reported. Thus, the 'quasi-aromaticity' of the [W_3S_4] ̄(4+) core of these cluster compounds is discussed.
基金supported by National Basic Research Program of China (2012CB910604)National Natural Science Foundation of China (21205027,21005079,20935004)+1 种基金Analytical Method Innovation Program of Ministry of Science and Technology of China (2010IM030500)Natural Science Foundation of Hebei Province (B2012201095)
文摘The cationic reagent 1-(3-aminopropyl)-3-butylimidazolium bromide(BAPI) was exploited for the derivatization of carboxyl groups on peptides.Nearly 100% derivatization efficiency was achieved with the synthetic peptide RVYVHPI(RI-7).Furthermore,the peptide derivative was stable in a 0.1% TFA/water solution or a 0.1%(v/v) TFA/acetonitrile/water solution for at least one week.The effect of BAPI derivatization on the ionization of the peptide RI-7 was further investigated,and the detection sensitivity was improved >42-fold via matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF MS),thus outperforming the commercial piperazine derivatization approach.Moreover,the charge states of the peptide were largely increased via BAPI derivatization by electrospray ionization(ESI) MS.The results indicate the potential merits of BAPI derivatization for high sensitivity peptide analysis by MS.
基金the financial supports from Sichuan Provincial Department of Education (11ZA108)National Natural Science Foundation of China (21202109 and 21072140)+1 种基金Special Funds of Sichuan Normal University for Sharing the Large Precision Equipments (DJ2012-07,DJ2011-16)Sichuan Normal University
文摘An inexpensive BF3·Et20-catalyzed annulation reaction of arylacetaldehydes with arylalkynes has been developed. Various substituted phenylacetaldehydes and phenylacetylenes can undergo this reaction, producing corresponding α-aryl substituted naphthalene derivatives. Use of inexpensive and readily available BF3·Et20 catalyst constitutes the most attractive advantage of this transformation.
基金Project supported by the Natural Science Foundation of Zhejiang Province (No. Y407168)the Foundation of Education of Zhejiang Province (No. Z200803599)the Opening Foundation of Zhejiang Provincial Top Key Discipline (No. 56310101634), China
文摘Both 1,5-benzodiazepine and quinoxaline derivatives are important heterocycles in pharmaceuticals. We describe an efficient and clean method for the synthesis of 1,5-benzodiazepines from o-phenylenediamine and ketones catalyzed by sodium tetrachloroaurate(Ⅲ) dihydrate under mild conditions. The catalyst was shown to be equally effective for the synthesis of quinoxalines from o-phenylenediamine and α-bromo ketones under the similar reaction conditions. This method produced good yields.
基金Supported by the National Basic Research Program of China(No.2010CB126106), the National Natural Science Foundation of China(Nos.21272129, 21372133), the National Key Technologies Research and Development Program, China(No. 2011BAE06B05-3) and Specialized Research Fund for the Doctorial Program of Higher Education, China(No.20110031110017).
文摘Caffeine is one of methyl xanthine compounds,which has the similar mode of action as ryanodine receptor insecticide.In order to find novel and efficient insecticide,structural modification of certain methyl xanthine compounds was made by introducing some common pesticidal active moieties into the structure of caffeine.Eleven novel methyl xanthine compounds were synthesized and characterized by 1H nuclear magnetic resonance(1H NMR),elemental analylsis or high-resolution mass spectrometry(HRMS).According to the biological activity results,it was found that these new compounds show moderate activity towards Mythimna separata Walker and Culex pipiens pallens.For example,compound 2d shows a lethality rate of 40% at 200 mg/L towards Mythimna separata Walker,compounds 2i and 2f show 56.7% and 53.3% lethality rates at 2 mg/L towards Culex pipiens pallens,which are all better than caffeine.In addition,some compounds of them show moderate antifungal activity to some plant pathogenous fungi.