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
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
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
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.
A ligand free, Palladium nanoparticles catalyzed synthesis of pyran derivatives using C-H activated compound, malononitrile and aryl aldehyde via Knoevenagel condensation followed by Michael addition reaction using Pa...A ligand free, Palladium nanoparticles catalyzed synthesis of pyran derivatives using C-H activated compound, malononitrile and aryl aldehyde via Knoevenagel condensation followed by Michael addition reaction using Palladium nanoparticles as catalyst in one-pot is described herein. The advantages of this method lie in its simplicity, low catalyst loading, cost effectiveness and easy to handle. The Palladium Nanoparticles can be reused without loss of activity even after recycling four times. The palladium nanoparticles were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM). The present method also allows us to synthesize highly functionalized title compounds from simple and readily available inputs.展开更多
The increasing medicinal importance of 19-norsteroids, particularly for oral contraceptives, has stimulated intensive research to continuously find more economic methods of either partial and total direct synthesis or...The increasing medicinal importance of 19-norsteroids, particularly for oral contraceptives, has stimulated intensive research to continuously find more economic methods of either partial and total direct synthesis or indirect synthesis via estrone of this class of compound.展开更多
A new polymer-supported reagent--poly{[4-hydroxy(tosyloxy)iodo]styrene} has good reactivity in the formation of 2-amino-4-arylthiazoles, and the procedure of regeneration and cycle are also described.
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.
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.
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.
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A ligand free, Palladium nanoparticles catalyzed synthesis of pyran derivatives using C-H activated compound, malononitrile and aryl aldehyde via Knoevenagel condensation followed by Michael addition reaction using Palladium nanoparticles as catalyst in one-pot is described herein. The advantages of this method lie in its simplicity, low catalyst loading, cost effectiveness and easy to handle. The Palladium Nanoparticles can be reused without loss of activity even after recycling four times. The palladium nanoparticles were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM). The present method also allows us to synthesize highly functionalized title compounds from simple and readily available inputs.
文摘The increasing medicinal importance of 19-norsteroids, particularly for oral contraceptives, has stimulated intensive research to continuously find more economic methods of either partial and total direct synthesis or indirect synthesis via estrone of this class of compound.
文摘A new polymer-supported reagent--poly{[4-hydroxy(tosyloxy)iodo]styrene} has good reactivity in the formation of 2-amino-4-arylthiazoles, and the procedure of regeneration and cycle are also described.
