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2018 Volume 81 Issue 11
2018, 81(11): 963-971
Abstract:
The rapid development of nanotechnology has promoted the production of core-shell nanoparticles as a new type of functional material. By rationally designing the core and shell composition, a series of core-shell nanomaterials with functional tunability can be constructed. The material can be used as a cathode electrode for oxygen reduction reaction (ORR) in fuel cells and exhibits excellent electrocatalytic performance. Based on the classification of different chemical properties of core and shell, this article reviews the application of core-shell electrode materials in ORR in recent years and proposes some existing challenges in order to provide ideas for current solutions to energy conversion and storage problems.
The rapid development of nanotechnology has promoted the production of core-shell nanoparticles as a new type of functional material. By rationally designing the core and shell composition, a series of core-shell nanomaterials with functional tunability can be constructed. The material can be used as a cathode electrode for oxygen reduction reaction (ORR) in fuel cells and exhibits excellent electrocatalytic performance. Based on the classification of different chemical properties of core and shell, this article reviews the application of core-shell electrode materials in ORR in recent years and proposes some existing challenges in order to provide ideas for current solutions to energy conversion and storage problems.
2018, 81(11): 972-980
Abstract:
Aminopeptidase N (APN) is an exopeptidase that widely exists in the body of mammals. It is recognized to have various physiological functions in human body. Herein, the development of fluorescent probes for aminopeptides N was reviewed and generally divided into two categories:affinity based fluorescent probes and reaction based fluorescent probes, with their advantages and shortcomings compared, which may illuminate the future development of APN fluorescent probes.
Aminopeptidase N (APN) is an exopeptidase that widely exists in the body of mammals. It is recognized to have various physiological functions in human body. Herein, the development of fluorescent probes for aminopeptides N was reviewed and generally divided into two categories:affinity based fluorescent probes and reaction based fluorescent probes, with their advantages and shortcomings compared, which may illuminate the future development of APN fluorescent probes.
2018, 81(11): 981-985, 991
Abstract:
Microcystins (MCs) are water soluble toxic compounds released from cyanobacteria (blue-green algae). MCs may induce apoptosis and promote tumor formation, posing a significant threat to the ecosystem integrity and human health. Recently, an increasing occurrence of toxic cyanobacterial outbreak results in the need of efficient treatment methods for MCs removal. Chemical oxidation processes provide a promising alternative treatment option because they completely degrade MCs and form less toxic by-products. In this paper, the current research status of conventional and advanced oxidation processes (AOPs) for MCs removal, in terms of the degradation efficiency, reaction kinetics, possible degradation mechanism, identity and toxicity of oxidation by-products, are summarized in brief. The advantages and disadvantages of each method are also compared. In addition, further research challenges and needs are also proposed.
Microcystins (MCs) are water soluble toxic compounds released from cyanobacteria (blue-green algae). MCs may induce apoptosis and promote tumor formation, posing a significant threat to the ecosystem integrity and human health. Recently, an increasing occurrence of toxic cyanobacterial outbreak results in the need of efficient treatment methods for MCs removal. Chemical oxidation processes provide a promising alternative treatment option because they completely degrade MCs and form less toxic by-products. In this paper, the current research status of conventional and advanced oxidation processes (AOPs) for MCs removal, in terms of the degradation efficiency, reaction kinetics, possible degradation mechanism, identity and toxicity of oxidation by-products, are summarized in brief. The advantages and disadvantages of each method are also compared. In addition, further research challenges and needs are also proposed.
2018, 81(11): 986-991
Abstract:
As a key intermediate for the synthesis of HIV intergrase inhibitors dolutegravir, the quality and price of (R)-3-amino-1-butanol have a significant impact on the quality and production cost of dolutegravir. In this paper, the synthesis of (R)-3-amino-1-butanol was reviewed from five aspects:chemical resolution, chiral synthesis, chemical induction, preparative chromatograph and enzymatic hydrolysis.
As a key intermediate for the synthesis of HIV intergrase inhibitors dolutegravir, the quality and price of (R)-3-amino-1-butanol have a significant impact on the quality and production cost of dolutegravir. In this paper, the synthesis of (R)-3-amino-1-butanol was reviewed from five aspects:chemical resolution, chiral synthesis, chemical induction, preparative chromatograph and enzymatic hydrolysis.
2018, 81(11): 992-999
Abstract:
The decomposition process of one of the best methanol catalyst precursors, zincian malachite, was studied, and the structural change during the decomposition was in situ observed by TEM. HRTEM, ED and STEM mapping analysis suggest that there are mainly four decomposition stages. That is, the zincian malachite crystal firstly decomposes at random zones and outer surface, causing local structural collapse, accompanying with holes formation in the bulk and amorphous diffused layer formation on the surface; then the holes grow larger and more holes appeare, and the collapsed layer on surface further diffuse. Meanwhile, CuO crystallizes gradually at both hole sites and diffused layer regions. Finally, the structure of zincian malachite completely collapses to afford intersected CuO and ZnO in the form of crystalline CuO separated by amorphous ZnO. After that, ZnO begin to crystallize under further heating to give the final calcined catalyst with interdispersed CuO crystallites and ZnO crystallites. The direct observation of structural change during decomposition promotes our understanding on the calcination process of methanol catalyst precursors, and gives clues for optimizing calcination condition.
The decomposition process of one of the best methanol catalyst precursors, zincian malachite, was studied, and the structural change during the decomposition was in situ observed by TEM. HRTEM, ED and STEM mapping analysis suggest that there are mainly four decomposition stages. That is, the zincian malachite crystal firstly decomposes at random zones and outer surface, causing local structural collapse, accompanying with holes formation in the bulk and amorphous diffused layer formation on the surface; then the holes grow larger and more holes appeare, and the collapsed layer on surface further diffuse. Meanwhile, CuO crystallizes gradually at both hole sites and diffused layer regions. Finally, the structure of zincian malachite completely collapses to afford intersected CuO and ZnO in the form of crystalline CuO separated by amorphous ZnO. After that, ZnO begin to crystallize under further heating to give the final calcined catalyst with interdispersed CuO crystallites and ZnO crystallites. The direct observation of structural change during decomposition promotes our understanding on the calcination process of methanol catalyst precursors, and gives clues for optimizing calcination condition.
2018, 81(11): 1000-1005
Abstract:
A concentrated electrolyte containing lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and tetramethylene sulfone (TMS) was prepared. The electrolyte samples were characterized by Fourier transform infrared spectroscopy. The electrochemical properties of electrolytes were researched by linear sweep voltammetry (LSV) and cyclic voltammetry (CV). The TMS/LiTFSI (mole ratio 2:1) concentrated electrolyte displayed satisfactory electrochemical and chemical stability, extended electrochemical window to 5.02V. In addition, The 2:1 concentrated electrolyte could effectively restrain Al foil corrosion. Notably, the concentrated electrolyte was suitable for 5 V-class LiNi0.5Mn1.5O4 cathode material. The LiNi0.5Mn1.5O4 half-cells based on TMS/LiTFSI concentrated electrolyte showed excellent rate capability and cycle performance. The half-cell returned to its original specific capacity at 0.1 C after high power charge and discharge, meanwhile the coulombic efficiency of the half-cell was above 92% at 0.2 C after the first 25 cycles.
A concentrated electrolyte containing lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and tetramethylene sulfone (TMS) was prepared. The electrolyte samples were characterized by Fourier transform infrared spectroscopy. The electrochemical properties of electrolytes were researched by linear sweep voltammetry (LSV) and cyclic voltammetry (CV). The TMS/LiTFSI (mole ratio 2:1) concentrated electrolyte displayed satisfactory electrochemical and chemical stability, extended electrochemical window to 5.02V. In addition, The 2:1 concentrated electrolyte could effectively restrain Al foil corrosion. Notably, the concentrated electrolyte was suitable for 5 V-class LiNi0.5Mn1.5O4 cathode material. The LiNi0.5Mn1.5O4 half-cells based on TMS/LiTFSI concentrated electrolyte showed excellent rate capability and cycle performance. The half-cell returned to its original specific capacity at 0.1 C after high power charge and discharge, meanwhile the coulombic efficiency of the half-cell was above 92% at 0.2 C after the first 25 cycles.
2018, 81(11): 1006-1014
Abstract:
Three kinds of MOFs, namely[Cd(tdc)(bpy)]n, [Zn(tdc)(bpy)]n and [Co(tdc)(phen)(OH)]n, were synthesized using thiophene-2, 5-dicarboxylic acid (tdc) as the main ligand and 4, 4-dipyridyl (bpy) or phenanthroline (phen) as the second ligand by hydrothermal method. Their structures were characterized and analyzed by X-ray single crystal diffractometer and infrared spectrometer. At the same time, the fluorescence properties and thermal stabilities of these three MOFs were measured by fluorescence spectrometer and thermogravimetric analyzer. Co-MOFs was modified to the surface of glassy carbon electrode (GCE), and its electrochemical behavior were studies through cyclic voltammetry (CV). The results indicated that these three kinds of MOFs have stronger fluorescence intensity and better thermal stability than ligands. The prepared Co-MOFs modified GCE showed stronger CV response than the bare GCE for potassium cyanide solution and pH 5 PBS solution containing 1.0mmol/L NaNO2. It is expected to be used as a modifier in modified GCE.
Three kinds of MOFs, namely[Cd(tdc)(bpy)]n, [Zn(tdc)(bpy)]n and [Co(tdc)(phen)(OH)]n, were synthesized using thiophene-2, 5-dicarboxylic acid (tdc) as the main ligand and 4, 4-dipyridyl (bpy) or phenanthroline (phen) as the second ligand by hydrothermal method. Their structures were characterized and analyzed by X-ray single crystal diffractometer and infrared spectrometer. At the same time, the fluorescence properties and thermal stabilities of these three MOFs were measured by fluorescence spectrometer and thermogravimetric analyzer. Co-MOFs was modified to the surface of glassy carbon electrode (GCE), and its electrochemical behavior were studies through cyclic voltammetry (CV). The results indicated that these three kinds of MOFs have stronger fluorescence intensity and better thermal stability than ligands. The prepared Co-MOFs modified GCE showed stronger CV response than the bare GCE for potassium cyanide solution and pH 5 PBS solution containing 1.0mmol/L NaNO2. It is expected to be used as a modifier in modified GCE.
2018, 81(11): 1015-1022
Abstract:
Nucleozin has good inhibitory activity as an inhibitor against influenza virus nucleoprotein. In this paper, we investigate the aromatic ring part which is connected directly with piperazine in the nucleozin molecular structure. A series of nucleozin derivatives were synthesized by palladium catalyzed coupling reaction, and the structure-activity relationship of this part in nucleozin molecule was clarified by detecting the inhibitory activities of the synthesized compounds on influenza virus H1N1. After replacing the chlorine atom in the molecule with a methyl group, it was found that the inhibitory activity is significantly improved compared with the prototype molecule nucleozin. This study has a significant meaning in the drug-like improvement of this kind of molecular.
Nucleozin has good inhibitory activity as an inhibitor against influenza virus nucleoprotein. In this paper, we investigate the aromatic ring part which is connected directly with piperazine in the nucleozin molecular structure. A series of nucleozin derivatives were synthesized by palladium catalyzed coupling reaction, and the structure-activity relationship of this part in nucleozin molecule was clarified by detecting the inhibitory activities of the synthesized compounds on influenza virus H1N1. After replacing the chlorine atom in the molecule with a methyl group, it was found that the inhibitory activity is significantly improved compared with the prototype molecule nucleozin. This study has a significant meaning in the drug-like improvement of this kind of molecular.
2018, 81(11): 1023-1027
Abstract:
In order to develop green chemistry and reduce the amount of toxic solvents in chemical reactions, 2, 3-dihydroquinazoline-4(1H)-one derivatives were synthesized successfully with 2-aminobenzamide and aldehyde as substrates and high temperature water as solvent in the absence of organic solvent and catalyst. The reaction temperature, reaction time and the effect of substituents on the aromatic ring on the reaction were investigated. Under the optimal conditions of molar ratio 1:1, temperature of 130℃ and reaction time of 1 h, the yield was 32.4%~85.7%.
In order to develop green chemistry and reduce the amount of toxic solvents in chemical reactions, 2, 3-dihydroquinazoline-4(1H)-one derivatives were synthesized successfully with 2-aminobenzamide and aldehyde as substrates and high temperature water as solvent in the absence of organic solvent and catalyst. The reaction temperature, reaction time and the effect of substituents on the aromatic ring on the reaction were investigated. Under the optimal conditions of molar ratio 1:1, temperature of 130℃ and reaction time of 1 h, the yield was 32.4%~85.7%.
2018, 81(11): 1028-1032
Abstract:
In this paper, two rutaecarpine derivatives 10-methoxy rutaecarpine and 10, 11-dimethoxy rutaecarpine were designed and synthesized, and the structures of the compounds were characterized by IR, NMR, MS and elemental analysis. Their UV and fluorescence properties were studied. The effects of compound structure, solvent and concentration on fluorescence intensity were investigated, and the fluorescence quantum yield was calculated.
In this paper, two rutaecarpine derivatives 10-methoxy rutaecarpine and 10, 11-dimethoxy rutaecarpine were designed and synthesized, and the structures of the compounds were characterized by IR, NMR, MS and elemental analysis. Their UV and fluorescence properties were studied. The effects of compound structure, solvent and concentration on fluorescence intensity were investigated, and the fluorescence quantum yield was calculated.
2018, 81(11): 1033-1043, 1032
Abstract:
Asphaltene components in heavy oil are prone to coalesce to form clusters, which seriously affect the processing and utilization efficiency of heavy oil. However, there are few studies on the coagulation of asphaltene, and its mechanism is not clear. In this paper, theoretical calculations are used to study the intermolecular interaction and solvation effects of asphaltene heterocycle models. It provides some data and theoretical support for the study of the coagulation of heavy oil and the development of coagulation inhibitors. (1)By using the density functional theory (DFT), in the M062X/6-31G (d) level, we can get 11 kinds of stable configurations of binary mixture systems composed of the fragments of asphaltene-heterocyclic molecules (dibenzofuran, acridine and carbazole). The geometries of stable configurations, NBO (natural bonding orbital) charges, Mulliken overlap, interaction energies and molecular orbital energies are analyzed, and the most stable two configurations are obtained. (2)The modeling and theoretical calculation of the solvation effect of asphaltene macromolecules in 13 solvents were carried out in the B3LYP/6-31G (d) level with the SMD model. Through the analysis of the electrostatic solvation free energy(ΔGelec), non-electrostatic solvation free energy(ΔGnonelec) and solvation free energy(ΔGsolv), we can conclude that the key to the solubility of asphaltene lies in the size of the long-range electrostatic effect.
Asphaltene components in heavy oil are prone to coalesce to form clusters, which seriously affect the processing and utilization efficiency of heavy oil. However, there are few studies on the coagulation of asphaltene, and its mechanism is not clear. In this paper, theoretical calculations are used to study the intermolecular interaction and solvation effects of asphaltene heterocycle models. It provides some data and theoretical support for the study of the coagulation of heavy oil and the development of coagulation inhibitors. (1)By using the density functional theory (DFT), in the M062X/6-31G (d) level, we can get 11 kinds of stable configurations of binary mixture systems composed of the fragments of asphaltene-heterocyclic molecules (dibenzofuran, acridine and carbazole). The geometries of stable configurations, NBO (natural bonding orbital) charges, Mulliken overlap, interaction energies and molecular orbital energies are analyzed, and the most stable two configurations are obtained. (2)The modeling and theoretical calculation of the solvation effect of asphaltene macromolecules in 13 solvents were carried out in the B3LYP/6-31G (d) level with the SMD model. Through the analysis of the electrostatic solvation free energy(ΔGelec), non-electrostatic solvation free energy(ΔGnonelec) and solvation free energy(ΔGsolv), we can conclude that the key to the solubility of asphaltene lies in the size of the long-range electrostatic effect.
2018, 81(11): 1044-1047
Abstract:
The creatinol phosphate was synthesized, and its structure was confirmed by IR, 1H NMR and elemental analysis. The crystal structure of creatinol phosphate belongs to monoclinic with space group of P21/n and crystal parameters of a = 1.01401(14) nm, b = 1.0912(15) nm, c = 1.7645(2) nm, α = 90.00°, β = 103.923(2)°, γ = 90.00°, V = 1.9036(5) nm3, Dc = 1.501 g·cm-3, Z = 8, F(000) = 912, μ = 0.288 mm-1. A crystal unit of the titled compound was selected as the initial structure and fully optimized. The atomic charges, frontier orbital energy and natural bond orbital were also discussed. This thesis provides the fundamental data for research of the structure and the property of the creatinol phosphate.
The creatinol phosphate was synthesized, and its structure was confirmed by IR, 1H NMR and elemental analysis. The crystal structure of creatinol phosphate belongs to monoclinic with space group of P21/n and crystal parameters of a = 1.01401(14) nm, b = 1.0912(15) nm, c = 1.7645(2) nm, α = 90.00°, β = 103.923(2)°, γ = 90.00°, V = 1.9036(5) nm3, Dc = 1.501 g·cm-3, Z = 8, F(000) = 912, μ = 0.288 mm-1. A crystal unit of the titled compound was selected as the initial structure and fully optimized. The atomic charges, frontier orbital energy and natural bond orbital were also discussed. This thesis provides the fundamental data for research of the structure and the property of the creatinol phosphate.
2018, 81(11): 1048-1051
Abstract:
A novel and efficient synthesis of flibanserin was reported. One pot reaction of benzaldehyde, N-phenyl hydroxylamine and trimethylsilyl cyanide promoted by diacetoxyiodobenzene was used to construct benzimidazolones, which is the key skeleton structure of flibanserin. Subsequently, it is reacted with 1, 2-dibromoethane to generate compound 8, which hydrolyzed in concentrated hydrochloric acid to produce intermediate 9. At last, intermediate 9 was reacted with 10 to obtain flibanserin with a total yield of 29%. The structure of all compounds was characterized by 1H NMR, 13C NMR and HRMS. This method has the advantages of inexpensive raw material, little byproduct and moderate yield.
A novel and efficient synthesis of flibanserin was reported. One pot reaction of benzaldehyde, N-phenyl hydroxylamine and trimethylsilyl cyanide promoted by diacetoxyiodobenzene was used to construct benzimidazolones, which is the key skeleton structure of flibanserin. Subsequently, it is reacted with 1, 2-dibromoethane to generate compound 8, which hydrolyzed in concentrated hydrochloric acid to produce intermediate 9. At last, intermediate 9 was reacted with 10 to obtain flibanserin with a total yield of 29%. The structure of all compounds was characterized by 1H NMR, 13C NMR and HRMS. This method has the advantages of inexpensive raw material, little byproduct and moderate yield.
2018, 81(11): 1052-1055
Abstract:
Chemical equilibrium constant can be obtained from the reaction isotherm. However, it is not easy to understand the contribution of mixed entropy to the chemical equilibrium by the reaction isotherm. An equation between Gibbs free energy and extent of reaction was obtained for ideal gas reactions. The equation was used for three ideal gas reactions. Based on them, the contribution of mixed entropy to the chemical equilibrium was analyzed.
Chemical equilibrium constant can be obtained from the reaction isotherm. However, it is not easy to understand the contribution of mixed entropy to the chemical equilibrium by the reaction isotherm. An equation between Gibbs free energy and extent of reaction was obtained for ideal gas reactions. The equation was used for three ideal gas reactions. Based on them, the contribution of mixed entropy to the chemical equilibrium was analyzed.
