Promoted and mediated by an ionic liquid-[bmim][BF4], fused pyrans or arylbis(4-hydroxy-6-methyl-2-oxo-2H-pyran-3- yl)methanes were efficiently and selectively prepared from the reaction of aldehyde and 4-hydroxy-6-...Promoted and mediated by an ionic liquid-[bmim][BF4], fused pyrans or arylbis(4-hydroxy-6-methyl-2-oxo-2H-pyran-3- yl)methanes were efficiently and selectively prepared from the reaction of aldehyde and 4-hydroxy-6-methyl-2-oxo-pyran with or without acetic anhydride. By using these novel procedures, pyrimidine nucleoside-fused pyran and arylbis(pyranon-3-yl)methane hybrids with potential biological activities were constructed.展开更多
The title compound N-tert-butyl-N(-(2,4-dichlorobenzoyl)-N-[1-(4-chlorophenyl)- 1,4-dihydro-6-methylpyridazine-4-oxo-3-carbonyl]hydrazine [(C23H_21N4O3Cl3)2·1.5H_2O, Mr = 1042.60] was prepared by the reaction of ...The title compound N-tert-butyl-N(-(2,4-dichlorobenzoyl)-N-[1-(4-chlorophenyl)- 1,4-dihydro-6-methylpyridazine-4-oxo-3-carbonyl]hydrazine [(C23H_21N4O3Cl3)2·1.5H_2O, Mr = 1042.60] was prepared by the reaction of 1-(4-chlorophenyl)-1,4-dihydro-4-oxo-6- methylpyridazine-3-carboxylic acid with chloroformate ethyl ester, then with N′-tert-butyl-N- (2,4-dichlorobenzoyl) hydrazine in the present of triethylamine. The crystal structure has been determined by X-ray diffraction. The crystal belongs to Monoclinic, space group P21/c, with unit cell constants a =11.4948(9), b=12.7495(10), c=35.854(3) ?, β =92.964(2)°, Z=4, V=5247.6(7) ?3, Dc = 1.320 Mg/m3, F(000) = 2156 , μ (MoKa)= 0.385, R = 0.0661, wR = 0.1875, for 9151 observed reflections( I >2σ(I)). The structure is a dimer linked by intermolecular hydrogen bond which can be observed between N(1)- H...O(6), N(5)- H...O(3). The distances are 2.068 and 2.027? respectively.展开更多
The crystal structure of the title compound ethyl 3-(4-chlorophenyl)-3,4-dihydro-6- methyl-4-oxo-2-(pyrrolidin-1-yl)furo[2,3-d]pyrimidine-5-carboxylate (C20H20ClN3O4, Mr= 401.84) has been prepared and determined...The crystal structure of the title compound ethyl 3-(4-chlorophenyl)-3,4-dihydro-6- methyl-4-oxo-2-(pyrrolidin-1-yl)furo[2,3-d]pyrimidine-5-carboxylate (C20H20ClN3O4, Mr= 401.84) has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a = 20.6215(9), b = 8.5311(4), c = 21.6886(9) A^°, β = 91.607(1)°, V = 3814.0(3)A^°^3, Z = 8, Dc = 1.400 g/cm^3, F(000) = 1680, μ = 0.233 mm^-1, R = 0.0718 and wR = 0.1545 for 6717 observed reflections with I 〉 2σ(I). X-ray diffraction analysis reveals two crystallographically independent molecules in the asymmetric unit.展开更多
The mechanisms about the water’s and methanol’s effects on the alcoholysis of N-benzyl-3-oxo-β-sultam together with their differences have been studied by using density func- tional theory at the B3LYP/6-31G* leve...The mechanisms about the water’s and methanol’s effects on the alcoholysis of N-benzyl-3-oxo-β-sultam together with their differences have been studied by using density func- tional theory at the B3LYP/6-31G* level. The results, in comparison with a previous study on the relative reaction without the assistance of water and methanol, show that the added water or methanol can remarkably reduce the energy barrier of alcoholysis reaction of N-benzyl-3-oxo- β-sultam and the most favorite pathway is the breaking of C–N bond instead of S–N. It is also found that the reaction energy barrier of methanol-assisted alcoholysis is a little higher than that of the water-assisted one.展开更多
A facile ndxture of the C-11 isomeric 3 - oxo-7αH-eudes ma-4-en- 9β, 1 2-diol has been achieved ffom oxycarvone. The C-11 configuration of natural product is established through comparison of IHNMR spectra between ...A facile ndxture of the C-11 isomeric 3 - oxo-7αH-eudes ma-4-en- 9β, 1 2-diol has been achieved ffom oxycarvone. The C-11 configuration of natural product is established through comparison of IHNMR spectra between synthatic 1b, or the mixture of 1a and 1b, and natural diol.展开更多
o-Carboxybenzaldehyde (1)and acetone gave the Claisen-Schmidt condensation product, which readily cyclizes on acidification to give 1-oxo-3-acetonyl-dihydrobenzo [c]furan(4)in 68% yield. Other methyl ketones behaved s...o-Carboxybenzaldehyde (1)and acetone gave the Claisen-Schmidt condensation product, which readily cyclizes on acidification to give 1-oxo-3-acetonyl-dihydrobenzo [c]furan(4)in 68% yield. Other methyl ketones behaved similarly.展开更多
The synthesis of 99-acetoxy-3(4), 11(13)-dien-5αH 7αH-12-eudesmanoic acid methyl ester (2) was achieved from oxycarvone. The key step is the p-toluenesulfonhydrazide assisted reductiv rearrangement reaction
Due to acidic solutions aggressiveness, corrosion inhibitors use is considered to be one the most practical methods to delay metals dissolution in the said solutions. In this study benzimidazolyl derivative namely 2-c...Due to acidic solutions aggressiveness, corrosion inhibitors use is considered to be one the most practical methods to delay metals dissolution in the said solutions. In this study benzimidazolyl derivative namely 2-cyanochalcones 2-(5-nitro-1,3-dihydrobenzimidazol-2-ylidene)-3-oxo-3-(2-oxo-2H-chromen-3-yl) propanenitrile which was synthesized was then applied as a corrosion inhibitor for copper in 1 M HNO<sub>3</sub> solution. The inhibition action of this molecule was evaluated by gravimetric and density functional theory (DFT) methods. It was found experimentally that this compound has a better inhibition performance and its adsorption on copper surface follows Langmuir adsorption isotherm. This adsorption evolves with temperature and inhibitor concentration, it is endothermic and occurs spontaneously with an increase in disorder. Corrosion kinetic parameters analysis supported by Adejo-Ekwenchi model revealed the existence of both physisorption and chemisorption. DFT calculations related that compound adsorption on copper surface is due to its electron donating and accepting capacity. The reactive regions specifying the electrophilic and nucleophilic attack sites were analyzed using Fukui and dual descriptor functions. Experimental results obtained were compared with the theoretical findings.展开更多
A series of novel unsymmetrical N-(4-oxo-2-phenyl-3(4H)-quinazolinoyl)-N-(aryl) acetamidines was synthesized by reacting ethyl(1H)-N-(4-oxo-2-phenylquinazolin-3(4H)-y1)ethanimidoate(2) and suitable react...A series of novel unsymmetrical N-(4-oxo-2-phenyl-3(4H)-quinazolinoyl)-N-(aryl) acetamidines was synthesized by reacting ethyl(1H)-N-(4-oxo-2-phenylquinazolin-3(4H)-y1)ethanimidoate(2) and suitable reactive aromatic amines.Structures' determination of the synthesized compounds was carried out using spectroscopic techniques including IR,~1H NMR,and mass spectrometry. Structural effects on reactivity were also studied.展开更多
The title compound ethyl 2-(6-(1,3-dioxo-4,5,6,7-tetrahydro-lH-isoindol-2(3H)- yl)-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4(3H)-yl) butanoate 3 was synthesized by the reaction of ethyl 2-(6-amino-7-fluoro-3-ox...The title compound ethyl 2-(6-(1,3-dioxo-4,5,6,7-tetrahydro-lH-isoindol-2(3H)- yl)-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4(3H)-yl) butanoate 3 was synthesized by the reaction of ethyl 2-(6-amino-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4(3H)-yl) butanoate with 4,5,6,7- tetraydrophthalic anhydride, and its structure was determined by X-ray single-crystal diffraction. The crystal belongs to the monoclinic system, space group P2 1/n with a = 9.3469(2), b = 16.7715(5), c = 13.7153(4) A, β= 104.9680(10)°, μ = 0.107 mm^-1, Mr = 430.42, V= 2077.08(10) ,A3, Z= 4, Dc = 1.376 g/cm3, F(000) = 904, T= 296(2) K, R = 0.0508 and wR = 0.1478.展开更多
A novel method for the preparation of highly functionalized 4-oxo-3-(1H-pyrrol-3-yl)-4H-chromenes(OPCMs)from 3-formylchromones andα-isocyanoacetates via an unprecedented three-component[1+1+3]cycloaddition reaction i...A novel method for the preparation of highly functionalized 4-oxo-3-(1H-pyrrol-3-yl)-4H-chromenes(OPCMs)from 3-formylchromones andα-isocyanoacetates via an unprecedented three-component[1+1+3]cycloaddition reaction in one pot was developed.The three-component cascade reaction was enabled by refluxing a mixture of the substrates in 1,4-dioxane in the presence of Ag_(2)CO_(3) as a Lewis acid promoter.As a result,a series of functionalized pyrroles(OPCMs,3),was prepared regioselectively and in high yields(80%-88%)through the formation of three bonds.This protocol can be used in the synthesis of OPCMs rather than through conventional,multi-step reactions and is suitable for both combinatorial and parallel syntheses of pyrroles.展开更多
基金the National Natural Science Foundation of China(No.20772025)the Program for Science & Technology Innovation Talents in Universities of Henan Province(No.2008HASTIT006)the Natural Science Foundation of Department of Education of Henan Province(No.2008A150013).
文摘Promoted and mediated by an ionic liquid-[bmim][BF4], fused pyrans or arylbis(4-hydroxy-6-methyl-2-oxo-2H-pyran-3- yl)methanes were efficiently and selectively prepared from the reaction of aldehyde and 4-hydroxy-6-methyl-2-oxo-pyran with or without acetic anhydride. By using these novel procedures, pyrimidine nucleoside-fused pyran and arylbis(pyranon-3-yl)methane hybrids with potential biological activities were constructed.
文摘The title compound N-tert-butyl-N(-(2,4-dichlorobenzoyl)-N-[1-(4-chlorophenyl)- 1,4-dihydro-6-methylpyridazine-4-oxo-3-carbonyl]hydrazine [(C23H_21N4O3Cl3)2·1.5H_2O, Mr = 1042.60] was prepared by the reaction of 1-(4-chlorophenyl)-1,4-dihydro-4-oxo-6- methylpyridazine-3-carboxylic acid with chloroformate ethyl ester, then with N′-tert-butyl-N- (2,4-dichlorobenzoyl) hydrazine in the present of triethylamine. The crystal structure has been determined by X-ray diffraction. The crystal belongs to Monoclinic, space group P21/c, with unit cell constants a =11.4948(9), b=12.7495(10), c=35.854(3) ?, β =92.964(2)°, Z=4, V=5247.6(7) ?3, Dc = 1.320 Mg/m3, F(000) = 2156 , μ (MoKa)= 0.385, R = 0.0661, wR = 0.1875, for 9151 observed reflections( I >2σ(I)). The structure is a dimer linked by intermolecular hydrogen bond which can be observed between N(1)- H...O(6), N(5)- H...O(3). The distances are 2.068 and 2.027? respectively.
基金supported by the Natural Science Foundation of Hubei Province (2006ABB016)Key Science Research Project of Hubei Provincial Department of Education (No.D200724001) the Science Research Project of Yunyang Medical College (No. 2006QDJ16)
文摘The crystal structure of the title compound ethyl 3-(4-chlorophenyl)-3,4-dihydro-6- methyl-4-oxo-2-(pyrrolidin-1-yl)furo[2,3-d]pyrimidine-5-carboxylate (C20H20ClN3O4, Mr= 401.84) has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a = 20.6215(9), b = 8.5311(4), c = 21.6886(9) A^°, β = 91.607(1)°, V = 3814.0(3)A^°^3, Z = 8, Dc = 1.400 g/cm^3, F(000) = 1680, μ = 0.233 mm^-1, R = 0.0718 and wR = 0.1545 for 6717 observed reflections with I 〉 2σ(I). X-ray diffraction analysis reveals two crystallographically independent molecules in the asymmetric unit.
基金This work was supported by the National Natural Science Foundation of China (No. 20373034 and 20603030)Post-doctor Research Foundation of Shandong Province (No. 200601007)
文摘The mechanisms about the water’s and methanol’s effects on the alcoholysis of N-benzyl-3-oxo-β-sultam together with their differences have been studied by using density func- tional theory at the B3LYP/6-31G* level. The results, in comparison with a previous study on the relative reaction without the assistance of water and methanol, show that the added water or methanol can remarkably reduce the energy barrier of alcoholysis reaction of N-benzyl-3-oxo- β-sultam and the most favorite pathway is the breaking of C–N bond instead of S–N. It is also found that the reaction energy barrier of methanol-assisted alcoholysis is a little higher than that of the water-assisted one.
文摘A facile ndxture of the C-11 isomeric 3 - oxo-7αH-eudes ma-4-en- 9β, 1 2-diol has been achieved ffom oxycarvone. The C-11 configuration of natural product is established through comparison of IHNMR spectra between synthatic 1b, or the mixture of 1a and 1b, and natural diol.
文摘o-Carboxybenzaldehyde (1)and acetone gave the Claisen-Schmidt condensation product, which readily cyclizes on acidification to give 1-oxo-3-acetonyl-dihydrobenzo [c]furan(4)in 68% yield. Other methyl ketones behaved similarly.
文摘The synthesis of 99-acetoxy-3(4), 11(13)-dien-5αH 7αH-12-eudesmanoic acid methyl ester (2) was achieved from oxycarvone. The key step is the p-toluenesulfonhydrazide assisted reductiv rearrangement reaction
文摘Due to acidic solutions aggressiveness, corrosion inhibitors use is considered to be one the most practical methods to delay metals dissolution in the said solutions. In this study benzimidazolyl derivative namely 2-cyanochalcones 2-(5-nitro-1,3-dihydrobenzimidazol-2-ylidene)-3-oxo-3-(2-oxo-2H-chromen-3-yl) propanenitrile which was synthesized was then applied as a corrosion inhibitor for copper in 1 M HNO<sub>3</sub> solution. The inhibition action of this molecule was evaluated by gravimetric and density functional theory (DFT) methods. It was found experimentally that this compound has a better inhibition performance and its adsorption on copper surface follows Langmuir adsorption isotherm. This adsorption evolves with temperature and inhibitor concentration, it is endothermic and occurs spontaneously with an increase in disorder. Corrosion kinetic parameters analysis supported by Adejo-Ekwenchi model revealed the existence of both physisorption and chemisorption. DFT calculations related that compound adsorption on copper surface is due to its electron donating and accepting capacity. The reactive regions specifying the electrophilic and nucleophilic attack sites were analyzed using Fukui and dual descriptor functions. Experimental results obtained were compared with the theoretical findings.
基金the financial support provided by the University of Peshawar,Pakistan in the form of a research grantHEJRIC University of Karachi,Pakistan for providing access to spectroscopic instruments
文摘A series of novel unsymmetrical N-(4-oxo-2-phenyl-3(4H)-quinazolinoyl)-N-(aryl) acetamidines was synthesized by reacting ethyl(1H)-N-(4-oxo-2-phenylquinazolin-3(4H)-y1)ethanimidoate(2) and suitable reactive aromatic amines.Structures' determination of the synthesized compounds was carried out using spectroscopic techniques including IR,~1H NMR,and mass spectrometry. Structural effects on reactivity were also studied.
基金Supported by the National Natural Science Foundation of China (20872033, 20575019)Natural Science Foundation of Hunan Province (07JJ1003)+1 种基金Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China) (KLCBTCMR2008-14)Scientific Research Fund of Science and Technology Department of Hunan Province (No. 2006GK3067)
文摘The title compound ethyl 2-(6-(1,3-dioxo-4,5,6,7-tetrahydro-lH-isoindol-2(3H)- yl)-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4(3H)-yl) butanoate 3 was synthesized by the reaction of ethyl 2-(6-amino-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4(3H)-yl) butanoate with 4,5,6,7- tetraydrophthalic anhydride, and its structure was determined by X-ray single-crystal diffraction. The crystal belongs to the monoclinic system, space group P2 1/n with a = 9.3469(2), b = 16.7715(5), c = 13.7153(4) A, β= 104.9680(10)°, μ = 0.107 mm^-1, Mr = 430.42, V= 2077.08(10) ,A3, Z= 4, Dc = 1.376 g/cm3, F(000) = 904, T= 296(2) K, R = 0.0508 and wR = 0.1478.
基金the Natural Science Foundation of Yunnan Province(No.2019FY003003)the National Natural Science Foundation of China(No.21662042)the Scientific and Technological Innovation Team of Green Synthesis and Activity Research of Natural-like Heterocyclic Compound Libraries in Universities of Yunnan Province(No.C17624011121).
文摘A novel method for the preparation of highly functionalized 4-oxo-3-(1H-pyrrol-3-yl)-4H-chromenes(OPCMs)from 3-formylchromones andα-isocyanoacetates via an unprecedented three-component[1+1+3]cycloaddition reaction in one pot was developed.The three-component cascade reaction was enabled by refluxing a mixture of the substrates in 1,4-dioxane in the presence of Ag_(2)CO_(3) as a Lewis acid promoter.As a result,a series of functionalized pyrroles(OPCMs,3),was prepared regioselectively and in high yields(80%-88%)through the formation of three bonds.This protocol can be used in the synthesis of OPCMs rather than through conventional,multi-step reactions and is suitable for both combinatorial and parallel syntheses of pyrroles.