Sulfated tin oxide (STO) has been found to be an efficient reusable solid superacid catalyst for C3-alkylation and O-alkylation of 4-hydroxycoumarins with benzylic, allylic alcohols/and corresponding acetates respecti...Sulfated tin oxide (STO) has been found to be an efficient reusable solid superacid catalyst for C3-alkylation and O-alkylation of 4-hydroxycoumarins with benzylic, allylic alcohols/and corresponding acetates respectively, in acetic acid under reflux conditions with good yield of products.展开更多
A facile procedure for the synthesis of 3-(2′-amino-3′-cyano-4′-arylpyrid-6′-yl) coumarins are being reported starting from 3- acetylcoumarin, aromatic aldehydes and malononitrile. The reactions were carried out...A facile procedure for the synthesis of 3-(2′-amino-3′-cyano-4′-arylpyrid-6′-yl) coumarins are being reported starting from 3- acetylcoumarin, aromatic aldehydes and malononitrile. The reactions were carried out on microwave irradiation in good yield with short time and easy work-up. The structures of all the compounds have been confirmed on the basis of their analytical, IR, ^1H NMR, and mass spectral data.展开更多
Eight new brominated 2'(4')-nitro-3-hydroxy diphenyl ethers have been designed and synthesized. The structures of new compounds were confirmed by ^1H NMR, IR and HRMS. The bioactivity tests showed that these compo...Eight new brominated 2'(4')-nitro-3-hydroxy diphenyl ethers have been designed and synthesized. The structures of new compounds were confirmed by ^1H NMR, IR and HRMS. The bioactivity tests showed that these compounds possessed antibacterial activities against the tested bacteria. These new compounds cannot be transformed into dioxins when they were manufactured and used.展开更多
An organic ligand and its Cu(II) complex formulated as (C13HloN203)·5H2O (H2L·5H2O, 1) and Cu(HL)2(phen)·0.125H2O (2, H2L = 4-carboxyl-4′-hydroxy azobenzene, phen = 1,10-phenanthroline) hav...An organic ligand and its Cu(II) complex formulated as (C13HloN203)·5H2O (H2L·5H2O, 1) and Cu(HL)2(phen)·0.125H2O (2, H2L = 4-carboxyl-4′-hydroxy azobenzene, phen = 1,10-phenanthroline) have been synthesized and structurally characterized by single-crystal X-ray diffraction. In the two compounds, H2L and HL exhibit a trans-conformation. Complex 2 shows a mononuclear Cu(Ⅱ) structure with the hydroxyl group of HL uncoordinated. Complex 2 is assembled into a three-dimensional (3D) supramolecular architecture by hydrogen bonds and π-π stacking interactions. H2L and compound 2 can detect NO2 via reversible and irreversible color changes, respectively. The mechanism for the color changes is investigated.展开更多
This paper reports the total synthesis of dimethyl 4-hydroxy-4’-methoxy-5,6,5’,6’-bismethylenedioxybiphenyl-2,2’-dicarboxylate(Ⅱ). Various conditions for bromination were tried to find the best one for synthesis ...This paper reports the total synthesis of dimethyl 4-hydroxy-4’-methoxy-5,6,5’,6’-bismethylenedioxybiphenyl-2,2’-dicarboxylate(Ⅱ). Various conditions for bromination were tried to find the best one for synthesis of the key intermediate compd 6.After Lllmann condensation of 6 with 8 and hydrogenolysis, the title compd Ⅱ was obtained.It was proved to be identical with the isolated metabolite of DDB by spectral data.展开更多
3-(5-(2.4-dichlorophyenyl)-4.5-dihydro-1H-pyrazol-3-yl)-4hydroxy-1-methylquinolin(1H)-one, 5-((4-hydroxy-8-methyl-2-oxo-1.2-dihydroquinolin-3-yl)methylene)-1-phenyl-2-hioxodihydropyrimidine-4.6(1H.5H)-dione, and 1-but...3-(5-(2.4-dichlorophyenyl)-4.5-dihydro-1H-pyrazol-3-yl)-4hydroxy-1-methylquinolin(1H)-one, 5-((4-hydroxy-8-methyl-2-oxo-1.2-dihydroquinolin-3-yl)methylene)-1-phenyl-2-hioxodihydropyrimidine-4.6(1H.5H)-dione, and 1-butyl-4-hydroxy-3-(5-styryl-4.5-dihydro-1H-pyrazol-3yl)quinolin-2(1H)-one were synthesized and characterized by spectroscopy analysis. These compounds are designated I, II and III, respectively. The antioxidants efficiency of the synthesized compounds in lubricating greases had been investigated using ASTM d-942 and ASTM d-664. The obtained data showed that the total acid number and oxygen pressure drop of these compounds in lubricating greases decrease in the order: Comp.III. < Comp.I. < Comp.II. The antioxidant efficiency of the prepared quinolinones derivatives was discussed. Acceptable correlations were obtained between the obtained oxidation inhibition and the calculated quantum chemical parameters.展开更多
The optically active R-4-phenyl-2-hydroxy butyrates were prepared by esterification of the racemic acid or transesterification of the racemic ester catalyzed by lipase from Candida cyclindra (CCL) in organic media.
Several new pyrazolo[4,3-b] pyridines 7a, b were prepared by reacting arylidenemalononitriles 1a, c or 1i, j with 4-nitrosoantipyrine 4. Reacting 1a, b, d with 4-azidomethylcarbonylantipyrine 8 give 2-aminopyrrole 14....Several new pyrazolo[4,3-b] pyridines 7a, b were prepared by reacting arylidenemalononitriles 1a, c or 1i, j with 4-nitrosoantipyrine 4. Reacting 1a, b, d with 4-azidomethylcarbonylantipyrine 8 give 2-aminopyrrole 14. Pyrano[3,2-c] quinolines 20a, b and 23 were obtained by reacting 4-hydroxyquinoline 15 with 1g, h, 2b respectively. Reaction of 1 with naphthalenediols 24, 27 and 29 yield naphthodipyrans 26a, b, 28a, b and 30a。展开更多
Ethyl ester of 5,7-dimethyl coumarin-4-acetic acid has been synthesized from 3,5-Xylenol in a two step sequence of reaction involving Pechmann cyclisation and acid catalyzed esterification. The title compound 2 crysta...Ethyl ester of 5,7-dimethyl coumarin-4-acetic acid has been synthesized from 3,5-Xylenol in a two step sequence of reaction involving Pechmann cyclisation and acid catalyzed esterification. The title compound 2 crystallizes in Monoclinic form, space group P 1 21/c 1, with a = 8.6248(4) ?, b = 18.9103(8) , c = 8.4204(4)?, β = 101.241(2)?, V = 1347.00(11) ?, D cal = 1.283 Mg/cm3, Z = 4. The molecule is stabilized by intermolecular C-H … O bonds.展开更多
以间苯二酚和乙酰乙酸乙酯为原料,氨基磺酸为催化剂,超声波辐射下合成了7-羟基-4-甲基香豆素,其结构经IR和1 H NMR表征。考察了超声波辐射功率和辐射时间及催化剂用量等因素对反应的影响。结果表明,在80 W辐射反应40min,间苯二酚11g(0.1...以间苯二酚和乙酰乙酸乙酯为原料,氨基磺酸为催化剂,超声波辐射下合成了7-羟基-4-甲基香豆素,其结构经IR和1 H NMR表征。考察了超声波辐射功率和辐射时间及催化剂用量等因素对反应的影响。结果表明,在80 W辐射反应40min,间苯二酚11g(0.1mol),n(间苯二酚)∶n(乙酰乙酸乙酯)∶n(氨基磺酸)=1.0∶1.1∶0.1条件下,7-羟基-4-甲基香豆素的收率到达95%以上。展开更多
文摘Sulfated tin oxide (STO) has been found to be an efficient reusable solid superacid catalyst for C3-alkylation and O-alkylation of 4-hydroxycoumarins with benzylic, allylic alcohols/and corresponding acetates respectively, in acetic acid under reflux conditions with good yield of products.
基金the Jiangsu Key Laboratory for Chemistry of Low-Dimensional Materials for financial support(No.JSKC07041).
文摘A facile procedure for the synthesis of 3-(2′-amino-3′-cyano-4′-arylpyrid-6′-yl) coumarins are being reported starting from 3- acetylcoumarin, aromatic aldehydes and malononitrile. The reactions were carried out on microwave irradiation in good yield with short time and easy work-up. The structures of all the compounds have been confirmed on the basis of their analytical, IR, ^1H NMR, and mass spectral data.
文摘Eight new brominated 2'(4')-nitro-3-hydroxy diphenyl ethers have been designed and synthesized. The structures of new compounds were confirmed by ^1H NMR, IR and HRMS. The bioactivity tests showed that these compounds possessed antibacterial activities against the tested bacteria. These new compounds cannot be transformed into dioxins when they were manufactured and used.
基金Supported by Chongqing Postdoctoral Science Foundation (No. XM2012002)
文摘An organic ligand and its Cu(II) complex formulated as (C13HloN203)·5H2O (H2L·5H2O, 1) and Cu(HL)2(phen)·0.125H2O (2, H2L = 4-carboxyl-4′-hydroxy azobenzene, phen = 1,10-phenanthroline) have been synthesized and structurally characterized by single-crystal X-ray diffraction. In the two compounds, H2L and HL exhibit a trans-conformation. Complex 2 shows a mononuclear Cu(Ⅱ) structure with the hydroxyl group of HL uncoordinated. Complex 2 is assembled into a three-dimensional (3D) supramolecular architecture by hydrogen bonds and π-π stacking interactions. H2L and compound 2 can detect NO2 via reversible and irreversible color changes, respectively. The mechanism for the color changes is investigated.
基金supports form the National"863"program of China(No.2006AA09Z446)from the overseas scholar supporting program(No.2008-51)+1 种基金from Shanxi Province Science Foundation for Youths(No.2009021041-1)from the innovative program of Shanxi Medical University(No.38) is gratefully acknowledged.
文摘This paper reports the total synthesis of dimethyl 4-hydroxy-4’-methoxy-5,6,5’,6’-bismethylenedioxybiphenyl-2,2’-dicarboxylate(Ⅱ). Various conditions for bromination were tried to find the best one for synthesis of the key intermediate compd 6.After Lllmann condensation of 6 with 8 and hydrogenolysis, the title compd Ⅱ was obtained.It was proved to be identical with the isolated metabolite of DDB by spectral data.
文摘3-(5-(2.4-dichlorophyenyl)-4.5-dihydro-1H-pyrazol-3-yl)-4hydroxy-1-methylquinolin(1H)-one, 5-((4-hydroxy-8-methyl-2-oxo-1.2-dihydroquinolin-3-yl)methylene)-1-phenyl-2-hioxodihydropyrimidine-4.6(1H.5H)-dione, and 1-butyl-4-hydroxy-3-(5-styryl-4.5-dihydro-1H-pyrazol-3yl)quinolin-2(1H)-one were synthesized and characterized by spectroscopy analysis. These compounds are designated I, II and III, respectively. The antioxidants efficiency of the synthesized compounds in lubricating greases had been investigated using ASTM d-942 and ASTM d-664. The obtained data showed that the total acid number and oxygen pressure drop of these compounds in lubricating greases decrease in the order: Comp.III. < Comp.I. < Comp.II. The antioxidant efficiency of the prepared quinolinones derivatives was discussed. Acceptable correlations were obtained between the obtained oxidation inhibition and the calculated quantum chemical parameters.
文摘The optically active R-4-phenyl-2-hydroxy butyrates were prepared by esterification of the racemic acid or transesterification of the racemic ester catalyzed by lipase from Candida cyclindra (CCL) in organic media.
文摘Several new pyrazolo[4,3-b] pyridines 7a, b were prepared by reacting arylidenemalononitriles 1a, c or 1i, j with 4-nitrosoantipyrine 4. Reacting 1a, b, d with 4-azidomethylcarbonylantipyrine 8 give 2-aminopyrrole 14. Pyrano[3,2-c] quinolines 20a, b and 23 were obtained by reacting 4-hydroxyquinoline 15 with 1g, h, 2b respectively. Reaction of 1 with naphthalenediols 24, 27 and 29 yield naphthodipyrans 26a, b, 28a, b and 30a。
文摘Ethyl ester of 5,7-dimethyl coumarin-4-acetic acid has been synthesized from 3,5-Xylenol in a two step sequence of reaction involving Pechmann cyclisation and acid catalyzed esterification. The title compound 2 crystallizes in Monoclinic form, space group P 1 21/c 1, with a = 8.6248(4) ?, b = 18.9103(8) , c = 8.4204(4)?, β = 101.241(2)?, V = 1347.00(11) ?, D cal = 1.283 Mg/cm3, Z = 4. The molecule is stabilized by intermolecular C-H … O bonds.
文摘以间苯二酚和乙酰乙酸乙酯为原料,氨基磺酸为催化剂,超声波辐射下合成了7-羟基-4-甲基香豆素,其结构经IR和1 H NMR表征。考察了超声波辐射功率和辐射时间及催化剂用量等因素对反应的影响。结果表明,在80 W辐射反应40min,间苯二酚11g(0.1mol),n(间苯二酚)∶n(乙酰乙酸乙酯)∶n(氨基磺酸)=1.0∶1.1∶0.1条件下,7-羟基-4-甲基香豆素的收率到达95%以上。