The reactions of Co(C1O4)2·6H2O and Co(NO3)2.6H2O with the di-Schiff base ligand N,N'-bis-(1-benzimidazo-2-yl-ethylidene)-ethane-1,2-diamine (LA) in ethanol have been investigated. The reactions of LA wi...The reactions of Co(C1O4)2·6H2O and Co(NO3)2.6H2O with the di-Schiff base ligand N,N'-bis-(1-benzimidazo-2-yl-ethylidene)-ethane-1,2-diamine (LA) in ethanol have been investigated. The reactions of LA with excess amount of cobalt salts yield the six-coordinate complexes [CoL2](ClO4)E·H2O 1 and [CoL2](NO3)E·H2O 2 as isolatable products (L= N-(1- benzimidazo-2-yl-ethylidene)-ethane-1,2-diamine), where L is a tri-dentate mono-Schiff base ligand, resulting from the hydrolysis of the precursor di-Schiff base LA. Both complexes were characterized by X-ray crystallography. Crystal data for complex 1: monoclinic, space group P21/c, a = 11.9214(10), b = 23.5828(17), c = 14.0387(12)A, β = 135.219(4)°, C22H30Cl2CoN8O9, Mr = 680.37, V = 2780.1(4) A^3 ,Z = 4, Dc = 1.625 g/cm^3,μ(MoKa) = 0.876 mm^-1, F(000) = 1404, the final R = 0.0725 and wR = 0.1530 for 5726 observed reflections (I 〉 2σ(I)). Crystal data for complex 2: monoclinic, space group P21/c, a = 18.2162(16), b = 10.0610(6), c = 18.593(2)A, β = 130.099(3)°, C22H30CoN10O7, Mr = 605.49, V = 2606.5(4) A3 Z = 4, Dc = 1.543 g/cm^3,μ(MoKa) = 0.722 mm^-1, F(000) = 1260, the final R = 0.0619 and wR = 0.1429 for 5194 observed reflections (I 〉 2σ(I)). X-ray diffraction analysis reveals that each cobalt atom in the two complexes is chelated by six nitrogen atoms from two tridentate iigands L, exhibiting a slightly distorted octahedral coordination sphere. In both complexes, the strong hydrogen-bonding interactions between the lattice waters and N-H groups of the ligands result in 1D chains which are further connected by ClO4^- (or NO3^-) groups to form a 3D framework. In complex 2, the strong π-π interactions increase the stability of the structure.展开更多
A novel fluorescent probe 9-(4-(1,2-diamine)benzene-N1-phenyl)acridine(DABPA) was synthesized for the detection of nitric oxide(NO) and characterized by IR, 1H-NMR and EI-MS spectroscopy. Based on a photoelect...A novel fluorescent probe 9-(4-(1,2-diamine)benzene-N1-phenyl)acridine(DABPA) was synthesized for the detection of nitric oxide(NO) and characterized by IR, 1H-NMR and EI-MS spectroscopy. Based on a photoelectron transfer mechanism, the fl uorescence intensities of DABPA were investigated with the different concentrations of NO. Under the optimal experimental conditions, the fl uorescence intensity of DABPA had a good linear relationship(R2=0.9977) with NO concentration in the range from 1×10-7 to 1.5×10-6 mol/L with a detection limit of 1×10-8 mol/L. The cytotoxicity induced by DABPA was evaluated by the MTT(3-(4,5-dimethylthiazol-2-yl)-2,5diphenyl tetrazolium bromide) assay for biological application. Furthermore, the probe DABPA had also been successfully applied to real-time image NO produced in PC12 cells in the presence of L-arginine.展开更多
A simple synthetic protocol has been developed involving the three-component reaction between 1,2-diamines, ethyl pyruvate and a-bromo ketones in the presence of Fe Cl3 as a catalyst. A number of pyrrolo[1,2-a]quinoxa...A simple synthetic protocol has been developed involving the three-component reaction between 1,2-diamines, ethyl pyruvate and a-bromo ketones in the presence of Fe Cl3 as a catalyst. A number of pyrrolo[1,2-a]quinoxaline and pyrrolo[1,2-a]pyrazine derivatives were synthesized in excellent yields using this protocol.展开更多
A facile and convenient synthesis method has been developed for substituted quinoxalines and 2H-benzo[b][1,4]oxazines from the reactions of a-bromoketones with benzene-1,2-diamine and 2-aminophenol, respectively, whic...A facile and convenient synthesis method has been developed for substituted quinoxalines and 2H-benzo[b][1,4]oxazines from the reactions of a-bromoketones with benzene-1,2-diamine and 2-aminophenol, respectively, which were catalyzed by tetrabutylammonium bromide(TBAB) in aqueous basic media.展开更多
A new series of quinoxalinophenazine derivatives were synthesized in good yields by the reaction of 2,3-dibromonaphthalene-1,4-dione with different aryl-1,2-diamines in DMF as solvent at 120-130℃ or under reflux cond...A new series of quinoxalinophenazine derivatives were synthesized in good yields by the reaction of 2,3-dibromonaphthalene-1,4-dione with different aryl-1,2-diamines in DMF as solvent at 120-130℃ or under reflux conditions. 3,12-dimethylbenzo[a]quinoxalino[2,3-c] phenazine with bidentate character reacts with mercury(II) bromide to give suitable crystals. All products were confirmed by IR, ^1H and ^13C NMR, and the metal complex by single-crystal X-ray method. The crystal(C24H16Br2HgN4, Mr = 720.82) belongs to the triclinic system, space group P1 with a = 10.186(6), b = 10.421(6), c = 11.470(7) A, α = 98.670(7), β = 95.069(7), γ = 109.831(7)°, V = 1119.4(12) A3, Z = 2, Dc = 2.139 Mg/m^3, μ = 10.46 mm^-1, F(000) = 676, R = 0.043 and wR = 0.115 for 3982 observed reflections with I 〉 2σ(I).展开更多
Nano-TiO_2 as an eco-friendly and efficient nanocatalyst was applied for quinoxaline preparation with improved yield.In this protocol,diketones and 1,2-diamines were condensed in the presence of catalyst at room tempe...Nano-TiO_2 as an eco-friendly and efficient nanocatalyst was applied for quinoxaline preparation with improved yield.In this protocol,diketones and 1,2-diamines were condensed in the presence of catalyst at room temperature.展开更多
基金the National Natural Science Foundation of China (20425313)the Natural Science Foundation of Fujian Province (2005HZ01-1, 2006L2005, 2006F3135, 2006J0183)
文摘The reactions of Co(C1O4)2·6H2O and Co(NO3)2.6H2O with the di-Schiff base ligand N,N'-bis-(1-benzimidazo-2-yl-ethylidene)-ethane-1,2-diamine (LA) in ethanol have been investigated. The reactions of LA with excess amount of cobalt salts yield the six-coordinate complexes [CoL2](ClO4)E·H2O 1 and [CoL2](NO3)E·H2O 2 as isolatable products (L= N-(1- benzimidazo-2-yl-ethylidene)-ethane-1,2-diamine), where L is a tri-dentate mono-Schiff base ligand, resulting from the hydrolysis of the precursor di-Schiff base LA. Both complexes were characterized by X-ray crystallography. Crystal data for complex 1: monoclinic, space group P21/c, a = 11.9214(10), b = 23.5828(17), c = 14.0387(12)A, β = 135.219(4)°, C22H30Cl2CoN8O9, Mr = 680.37, V = 2780.1(4) A^3 ,Z = 4, Dc = 1.625 g/cm^3,μ(MoKa) = 0.876 mm^-1, F(000) = 1404, the final R = 0.0725 and wR = 0.1530 for 5726 observed reflections (I 〉 2σ(I)). Crystal data for complex 2: monoclinic, space group P21/c, a = 18.2162(16), b = 10.0610(6), c = 18.593(2)A, β = 130.099(3)°, C22H30CoN10O7, Mr = 605.49, V = 2606.5(4) A3 Z = 4, Dc = 1.543 g/cm^3,μ(MoKa) = 0.722 mm^-1, F(000) = 1260, the final R = 0.0619 and wR = 0.1429 for 5194 observed reflections (I 〉 2σ(I)). X-ray diffraction analysis reveals that each cobalt atom in the two complexes is chelated by six nitrogen atoms from two tridentate iigands L, exhibiting a slightly distorted octahedral coordination sphere. In both complexes, the strong hydrogen-bonding interactions between the lattice waters and N-H groups of the ligands result in 1D chains which are further connected by ClO4^- (or NO3^-) groups to form a 3D framework. In complex 2, the strong π-π interactions increase the stability of the structure.
基金Funded by the National Natural Science Foundation of China(Nos.50802069,81100890,51272191)the Fundamental Research Funds for the Central Unversities(WUT:2013-IV-010)the Students Innovation and Entrepreneurship Training Program of WHUT(20141049701012)
文摘A novel fluorescent probe 9-(4-(1,2-diamine)benzene-N1-phenyl)acridine(DABPA) was synthesized for the detection of nitric oxide(NO) and characterized by IR, 1H-NMR and EI-MS spectroscopy. Based on a photoelectron transfer mechanism, the fl uorescence intensities of DABPA were investigated with the different concentrations of NO. Under the optimal experimental conditions, the fl uorescence intensity of DABPA had a good linear relationship(R2=0.9977) with NO concentration in the range from 1×10-7 to 1.5×10-6 mol/L with a detection limit of 1×10-8 mol/L. The cytotoxicity induced by DABPA was evaluated by the MTT(3-(4,5-dimethylthiazol-2-yl)-2,5diphenyl tetrazolium bromide) assay for biological application. Furthermore, the probe DABPA had also been successfully applied to real-time image NO produced in PC12 cells in the presence of L-arginine.
基金Sanandaj Branch,Islamic Azad UniversityResearch Council for the financial support of this research
文摘A simple synthetic protocol has been developed involving the three-component reaction between 1,2-diamines, ethyl pyruvate and a-bromo ketones in the presence of Fe Cl3 as a catalyst. A number of pyrrolo[1,2-a]quinoxaline and pyrrolo[1,2-a]pyrazine derivatives were synthesized in excellent yields using this protocol.
基金Supported by the National Natural Science Foundation of China(Nos.20572013 and 20711130229)the Department of Science and Technology of Jilin Province, China(No.20050309-2).
文摘A facile and convenient synthesis method has been developed for substituted quinoxalines and 2H-benzo[b][1,4]oxazines from the reactions of a-bromoketones with benzene-1,2-diamine and 2-aminophenol, respectively, which were catalyzed by tetrabutylammonium bromide(TBAB) in aqueous basic media.
文摘A new series of quinoxalinophenazine derivatives were synthesized in good yields by the reaction of 2,3-dibromonaphthalene-1,4-dione with different aryl-1,2-diamines in DMF as solvent at 120-130℃ or under reflux conditions. 3,12-dimethylbenzo[a]quinoxalino[2,3-c] phenazine with bidentate character reacts with mercury(II) bromide to give suitable crystals. All products were confirmed by IR, ^1H and ^13C NMR, and the metal complex by single-crystal X-ray method. The crystal(C24H16Br2HgN4, Mr = 720.82) belongs to the triclinic system, space group P1 with a = 10.186(6), b = 10.421(6), c = 11.470(7) A, α = 98.670(7), β = 95.069(7), γ = 109.831(7)°, V = 1119.4(12) A3, Z = 2, Dc = 2.139 Mg/m^3, μ = 10.46 mm^-1, F(000) = 676, R = 0.043 and wR = 0.115 for 3982 observed reflections with I 〉 2σ(I).
基金supported by the Natural Science Foundation of China(No.20272047,20572086)the Gansu Natural Science Foundation of China(No.0308RJZA-100)Key Laboratory of Eco-Environment-Related Polymer Material(Northwest Normal University),Ministry of the Education of China
基金Financial support for this work by the Research Council of Yazd University is gratefully acknowledged
文摘Nano-TiO_2 as an eco-friendly and efficient nanocatalyst was applied for quinoxaline preparation with improved yield.In this protocol,diketones and 1,2-diamines were condensed in the presence of catalyst at room temperature.