Dihydro-3-hydrozinocarbonyl-6-pyridazinone(compound 2) were prepared from α-ketoglutaric acid and hydrazine hydrate. A series of N-aryl-2-(1′,6′-dihydro-6′-pyridazinone-3′-carbonyl) thiosemicarbazides 3a_3f were ...Dihydro-3-hydrozinocarbonyl-6-pyridazinone(compound 2) were prepared from α-ketoglutaric acid and hydrazine hydrate. A series of N-aryl-2-(1′,6′-dihydro-6′-pyridazinone-3′-carbonyl) thiosemicarbazides 3a_3f were synthesized from the reaction of aryl isothiocyanates with compound 2. The terminal compounds 1,3,4-thiadiazole, 1,3,4-oxadiazole and 1,2,4-triazol-5-thione derivatives were cyclized from compounds 3a_3f. Their structures were confirmed by IR, 1H NMR, MS and elemental analyses.展开更多
A series of 1,3,4-oxadiazole or 1,3,4-thiadiazole-substituted pyrazole derivatives were synthesized from 4-pyrazole formhydrazide; their biological activities were studied. The structures of all the new compounds were...A series of 1,3,4-oxadiazole or 1,3,4-thiadiazole-substituted pyrazole derivatives were synthesized from 4-pyrazole formhydrazide; their biological activities were studied. The structures of all the new compounds were confirmed by means of spectroscopic methods and microanalyses. The preliminary bioassay results indicate that some compounds of them have a good fungicidal activity against Phoma asparagi and Physalospora piricola Nose.展开更多
Twenty-six novel benzoylphenylurea chitin inhibitor derivatives have been synthesized in over 30~50% yield from chlorothalonil 1 via sequential fluorine exchange, aminolysis, hydrolysis, decarboxylation and acylation ...Twenty-six novel benzoylphenylurea chitin inhibitor derivatives have been synthesized in over 30~50% yield from chlorothalonil 1 via sequential fluorine exchange, aminolysis, hydrolysis, decarboxylation and acylation reactions.展开更多
A novel gradient pressurized capillary electrochromatography (pCEC) instrument was developed to separate peptides. Two gradient elution modes, hydrophobic and hydrophilic interaction mode in pCEC, were performed on t...A novel gradient pressurized capillary electrochromatography (pCEC) instrument was developed to separate peptides. Two gradient elution modes, hydrophobic and hydrophilic interaction mode in pCEC, were performed on this instrument. Baseline separation of six peptides was obtained on two gradient modes with C18 column and strong cationic exchange column respectively. The effects of mixer volume and total flow rate of pumps on resolution were also discussed.展开更多
The synthesis of 2-alkyl(aryl)-3-methylthiopyrano[4,3-c]pyrazol-4(2H)-ones via 5, 6- dihydro-2H-pyran-2, 4-dione-3-dithioacetals with (un)substituted hydrazines is described and the mechanism of the formation of title...The synthesis of 2-alkyl(aryl)-3-methylthiopyrano[4,3-c]pyrazol-4(2H)-ones via 5, 6- dihydro-2H-pyran-2, 4-dione-3-dithioacetals with (un)substituted hydrazines is described and the mechanism of the formation of title compounds is discussed. Their structures were confirmed by 1HNMR spectra and elemental analysis.展开更多
Paeonol was prepared by the extraction method from Moutan Cortex. Its crystal struc- ture was determined by single-crystal X-ray diffraction.The compound crystallizes in the monoclinic sys- tem, space group P21/...Paeonol was prepared by the extraction method from Moutan Cortex. Its crystal struc- ture was determined by single-crystal X-ray diffraction.The compound crystallizes in the monoclinic sys- tem, space group P21/c with a = 6.724(4), b = 8.792(6), c = 14.689(10) ?, β = 100.138(11)o, V = 854.8(10) ?3, Mr = 166.17, Z = 4, F(000) = 352, Dc = 1.291 g/cm3, μ = 0.097 mm-1, the final R = 0.0454 and wR = 0.0988 for 845 observed reflections with I > 2σ(I).展开更多
Dimethyl-1-(1, 2, 4-triazol) -2- butanone was treated with aqueous formaldehyde to give an additional product, and subsequent elimination by acetic anhydride yielded 4, 4-dimethyl-2-(1, 2, 4-triazol)-1-penten-3-one. ...Dimethyl-1-(1, 2, 4-triazol) -2- butanone was treated with aqueous formaldehyde to give an additional product, and subsequent elimination by acetic anhydride yielded 4, 4-dimethyl-2-(1, 2, 4-triazol)-1-penten-3-one. Further addition with substituted amines provided a series of (1, 2, 4-triazol)-4, 4-dimethyl-3-pentanone, which were then reduced by KBH4 to obtain a series of (1, 2, 4-triazol)-4, 4-dimethyl-3-pentanol. Their structures were confirmed by 1HNMR and elemental analysis. The results of bioassay showed that the title products possess good fungicidal activities.展开更多
A novel b-cyclodextrin dimer bearing 2, 9-diformyl-1, 10-phenanthroline tether 4 has been synthesized and its inclusion complexation behavior with two triangular model substrates (RhB and BG) has been investigated thr...A novel b-cyclodextrin dimer bearing 2, 9-diformyl-1, 10-phenanthroline tether 4 has been synthesized and its inclusion complexation behavior with two triangular model substrates (RhB and BG) has been investigated through fluorescence and ultraviolet spectrometry. The result obtained indicated that novel bridged bis(b-cyclodextrin)s could significantly enhance the original molecular binding ability of native b-cyclodextrin by cooperative binding of two hydrophobic cavities.展开更多
The crystal of the title compound, 5-diazo-4-ethoxycarbonyl-3-methylthio pyrazole, has been prepared and determined by X-ray diffraction. The crystal belongs to the monoclinic system, space group C2/c with a = 29.174(...The crystal of the title compound, 5-diazo-4-ethoxycarbonyl-3-methylthio pyrazole, has been prepared and determined by X-ray diffraction. The crystal belongs to the monoclinic system, space group C2/c with a = 29.174(8), b = 4.7592(12), c = 15.956(4) ? b = 117.632(4), C7H8N4O2S, Mr = 212.23, V = 1962.7(9) ?, Z = 8, Dx = 1.436 g/cm3, S = 1.000, m(MoKa) = 0.31 mm-1, T = 298(2) K, F(000) = 880, R = 0.0658 and wR = 0.1741 for 1091 independent reflections with I ≥ 2s(I). The crystal of the title compound is formed with p-p interactions through electrostatic attractions. Moreover, no HSO4- exists in the crystal structure. Therefore, only diazo pyrazole was obtained rather than either diazonium salt of the corresponding pyrazole or diazoaminopyrazole when 5-amino-4-ethoxycarbonyl-3-methylthio pyrazole was diazotized with sodium nitrite, catalyzed by sulfuric acid at 0 ℃.展开更多
Two allelopathic rice accessions, PI312777 and Allelopathy1, significantly suppressedthe growth of associated weeds in the field. Moreover, their weed-suppressing effectswere correlated with the cultivation patterns. ...Two allelopathic rice accessions, PI312777 and Allelopathy1, significantly suppressedthe growth of associated weeds in the field. Moreover, their weed-suppressing effectswere correlated with the cultivation patterns. The weed-suppressing effects of throwingand transplanting were more effective than that of direct seeding. Furthermore, theamounts of allelochemicals (resorcinols, flavones and hydroxamic acids) produced andreleased from two allelopathic rice accessions were much higher than that from a non-allelopathic rice variety Hua-Jing-Xian1, and reached the maximum concentration at the6th leaf stage. Differences in the weed-suppressing effects of rice accessions appear toresult from the accessions producing and releasing different amounts of allelochemicalsin the field. Further research confirmed that in PI312777 plants, allelochemicals weresynthesized by the above-ground parts, and then secreted through the root tissues. Roottissues of PI312777 plants never produced the allelochemicals. Root exudates fromPI312777 could significantly inhibit the growth of E. crus-galli surrounding rice plantsin water culture. However, when activated carbon was added to the culture solution, whichcould absorb allelochemicals from root exudates, the growth of E. crus-galli was nolonger significantly inhibited. Weed-suppressing effects of rice accessions depended onallelopathy, cultivation patterns and other factors in rice fields, while allelopathywas one of important factors. Interestingly, the amounts of allelochemicals produced andreleased from allelopathic rice plants may be induced by the presence of E. crus-galli.This suggests that there is a possible chemical recognition between rice and E. crus-galli.展开更多
A novel β-cyclodextrin derivative, L-cystine bridged bis(β-cyclodextrin) 1 has been synthesized and characterized by ^1H NMR, ^13C NMR, IR, Raman and combustion analyses. Spectrofluorometric titrations have been per...A novel β-cyclodextrin derivative, L-cystine bridged bis(β-cyclodextrin) 1 has been synthesized and characterized by ^1H NMR, ^13C NMR, IR, Raman and combustion analyses. Spectrofluorometric titrations have been performed in aqueous phosphate buffer solution (pH=7.20)at 25℃ to give the complex stability constants (Ks) and Gibbs free energy changes (-△G°) for the stoichiometric 1:1 inclusion complexation of 1 with four dyes. The binding abilities and molecular selectivities are discussed from the viewpoint of size/shape-fit and electrostatic interactions between hosts and vips. 2D ROESY investigation for the complexation between host and vip further confirms the cooperative binding of bridged cyclodextrin 1 with vip.展开更多
文摘Dihydro-3-hydrozinocarbonyl-6-pyridazinone(compound 2) were prepared from α-ketoglutaric acid and hydrazine hydrate. A series of N-aryl-2-(1′,6′-dihydro-6′-pyridazinone-3′-carbonyl) thiosemicarbazides 3a_3f were synthesized from the reaction of aryl isothiocyanates with compound 2. The terminal compounds 1,3,4-thiadiazole, 1,3,4-oxadiazole and 1,2,4-triazol-5-thione derivatives were cyclized from compounds 3a_3f. Their structures were confirmed by IR, 1H NMR, MS and elemental analyses.
基金Supported by the National Natural Science Foundation of China(No.2 0 2 0 2 0 0 3) and the state's"86 3"Project(No.2 0 0 1AA2 35 0 11)
文摘A series of 1,3,4-oxadiazole or 1,3,4-thiadiazole-substituted pyrazole derivatives were synthesized from 4-pyrazole formhydrazide; their biological activities were studied. The structures of all the new compounds were confirmed by means of spectroscopic methods and microanalyses. The preliminary bioassay results indicate that some compounds of them have a good fungicidal activity against Phoma asparagi and Physalospora piricola Nose.
基金support of the Natural Science Foundation of Yunnan Province(1999B0005M)the Open Foundation of State Key Laboratory of Elemento-Organic Chemistry,Nankai University
文摘Twenty-six novel benzoylphenylurea chitin inhibitor derivatives have been synthesized in over 30~50% yield from chlorothalonil 1 via sequential fluorine exchange, aminolysis, hydrolysis, decarboxylation and acylation reactions.
基金The study is supported by NNSFC,grant No.20175010.
文摘A novel gradient pressurized capillary electrochromatography (pCEC) instrument was developed to separate peptides. Two gradient elution modes, hydrophobic and hydrophilic interaction mode in pCEC, were performed on this instrument. Baseline separation of six peptides was obtained on two gradient modes with C18 column and strong cationic exchange column respectively. The effects of mixer volume and total flow rate of pumps on resolution were also discussed.
文摘The synthesis of 2-alkyl(aryl)-3-methylthiopyrano[4,3-c]pyrazol-4(2H)-ones via 5, 6- dihydro-2H-pyran-2, 4-dione-3-dithioacetals with (un)substituted hydrazines is described and the mechanism of the formation of title compounds is discussed. Their structures were confirmed by 1HNMR spectra and elemental analysis.
文摘Paeonol was prepared by the extraction method from Moutan Cortex. Its crystal struc- ture was determined by single-crystal X-ray diffraction.The compound crystallizes in the monoclinic sys- tem, space group P21/c with a = 6.724(4), b = 8.792(6), c = 14.689(10) ?, β = 100.138(11)o, V = 854.8(10) ?3, Mr = 166.17, Z = 4, F(000) = 352, Dc = 1.291 g/cm3, μ = 0.097 mm-1, the final R = 0.0454 and wR = 0.0988 for 845 observed reflections with I > 2σ(I).
文摘Dimethyl-1-(1, 2, 4-triazol) -2- butanone was treated with aqueous formaldehyde to give an additional product, and subsequent elimination by acetic anhydride yielded 4, 4-dimethyl-2-(1, 2, 4-triazol)-1-penten-3-one. Further addition with substituted amines provided a series of (1, 2, 4-triazol)-4, 4-dimethyl-3-pentanone, which were then reduced by KBH4 to obtain a series of (1, 2, 4-triazol)-4, 4-dimethyl-3-pentanol. Their structures were confirmed by 1HNMR and elemental analysis. The results of bioassay showed that the title products possess good fungicidal activities.
基金This work was supported by the National Natural Science Foundation (No.299925908 and 29972029) of China Tianjin Natural Science Foundation (No.013613511) the Foundation of Ministry of Education, which are gratefully acknowledged.
文摘A novel b-cyclodextrin dimer bearing 2, 9-diformyl-1, 10-phenanthroline tether 4 has been synthesized and its inclusion complexation behavior with two triangular model substrates (RhB and BG) has been investigated through fluorescence and ultraviolet spectrometry. The result obtained indicated that novel bridged bis(b-cyclodextrin)s could significantly enhance the original molecular binding ability of native b-cyclodextrin by cooperative binding of two hydrophobic cavities.
基金Project supported by the National Natural Science Foundation of China (No. 20172031) the Research Fund for the Doctoral Program of High Education,China
文摘The crystal of the title compound, 5-diazo-4-ethoxycarbonyl-3-methylthio pyrazole, has been prepared and determined by X-ray diffraction. The crystal belongs to the monoclinic system, space group C2/c with a = 29.174(8), b = 4.7592(12), c = 15.956(4) ? b = 117.632(4), C7H8N4O2S, Mr = 212.23, V = 1962.7(9) ?, Z = 8, Dx = 1.436 g/cm3, S = 1.000, m(MoKa) = 0.31 mm-1, T = 298(2) K, F(000) = 880, R = 0.0658 and wR = 0.1741 for 1091 independent reflections with I ≥ 2s(I). The crystal of the title compound is formed with p-p interactions through electrostatic attractions. Moreover, no HSO4- exists in the crystal structure. Therefore, only diazo pyrazole was obtained rather than either diazonium salt of the corresponding pyrazole or diazoaminopyrazole when 5-amino-4-ethoxycarbonyl-3-methylthio pyrazole was diazotized with sodium nitrite, catalyzed by sulfuric acid at 0 ℃.
基金supported by the National Natural Science Foundation of China(30070130)the Natural Science Foundation of Guangdong Province,China(021045)+1 种基金National Key Technologies R&D Program in the Tenth Five-Year of China(2001BA509B07)the Scientific Fund for Scholars Returning Overseas of Ministry of Education,China(2001-498).
文摘Two allelopathic rice accessions, PI312777 and Allelopathy1, significantly suppressedthe growth of associated weeds in the field. Moreover, their weed-suppressing effectswere correlated with the cultivation patterns. The weed-suppressing effects of throwingand transplanting were more effective than that of direct seeding. Furthermore, theamounts of allelochemicals (resorcinols, flavones and hydroxamic acids) produced andreleased from two allelopathic rice accessions were much higher than that from a non-allelopathic rice variety Hua-Jing-Xian1, and reached the maximum concentration at the6th leaf stage. Differences in the weed-suppressing effects of rice accessions appear toresult from the accessions producing and releasing different amounts of allelochemicalsin the field. Further research confirmed that in PI312777 plants, allelochemicals weresynthesized by the above-ground parts, and then secreted through the root tissues. Roottissues of PI312777 plants never produced the allelochemicals. Root exudates fromPI312777 could significantly inhibit the growth of E. crus-galli surrounding rice plantsin water culture. However, when activated carbon was added to the culture solution, whichcould absorb allelochemicals from root exudates, the growth of E. crus-galli was nolonger significantly inhibited. Weed-suppressing effects of rice accessions depended onallelopathy, cultivation patterns and other factors in rice fields, while allelopathywas one of important factors. Interestingly, the amounts of allelochemicals produced andreleased from allelopathic rice plants may be induced by the presence of E. crus-galli.This suggests that there is a possible chemical recognition between rice and E. crus-galli.
文摘A novel β-cyclodextrin derivative, L-cystine bridged bis(β-cyclodextrin) 1 has been synthesized and characterized by ^1H NMR, ^13C NMR, IR, Raman and combustion analyses. Spectrofluorometric titrations have been performed in aqueous phosphate buffer solution (pH=7.20)at 25℃ to give the complex stability constants (Ks) and Gibbs free energy changes (-△G°) for the stoichiometric 1:1 inclusion complexation of 1 with four dyes. The binding abilities and molecular selectivities are discussed from the viewpoint of size/shape-fit and electrostatic interactions between hosts and vips. 2D ROESY investigation for the complexation between host and vip further confirms the cooperative binding of bridged cyclodextrin 1 with vip.
