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2017 Volume 28 Issue 8
2017, 28(8): 1625-1630
doi: 10.1016/j.cclet.2017.05.024
Abstract:
In this review, we highlight the latest development of multi-channel microfluidic chip-mass spectrometry (chip-MS) in cell analysis and metabolite detection. Following a brief introduction about history and development of multi-channel microchip and MS combination, we will elaborate the key issues of constructing chip-MS platform interface. Then exciting progresses made in this field should be reviewed with well exemplified works, including chip-MS technology for cell introduction, pretreatment of cell secretions and cell metabolite analysis. We will also describe the development of integrated total analysis systems proposed by our group. We hope this brief review will inspire interested readers and provide knowledge about chip-MS platform in the bioanalysis field, particularly in cell analysis and metabolite identifying applications.
In this review, we highlight the latest development of multi-channel microfluidic chip-mass spectrometry (chip-MS) in cell analysis and metabolite detection. Following a brief introduction about history and development of multi-channel microchip and MS combination, we will elaborate the key issues of constructing chip-MS platform interface. Then exciting progresses made in this field should be reviewed with well exemplified works, including chip-MS technology for cell introduction, pretreatment of cell secretions and cell metabolite analysis. We will also describe the development of integrated total analysis systems proposed by our group. We hope this brief review will inspire interested readers and provide knowledge about chip-MS platform in the bioanalysis field, particularly in cell analysis and metabolite identifying applications.
2017, 28(8): 1631-1639
doi: 10.1016/j.cclet.2017.04.022
Abstract:
Bottom-up approach to constructing low-dimensional nanostructures on surfaces with terminal alkynes has drawn great interest because of its potential applications in fabricating advanced functional nanomaterials. The diversity of the achieved products manifests rich chemistry of terminal alkynes and hence careful linking strategies and proper controlling methodologies are required for selective preparations of high-quality target nanoarchitectures. This review summarizes various on-surface linking strategies for terminal alkynes, including non-bonding interactions as well as organometallic and covalent bonds, and presents examples to show effective control of surface assemblies and reactions of terminal alkynes by variations of the precursor structures, substrates and activation modes. Systematic studies of the on-surface linkage of terminal alkynes may help efficient and predictable preparations of surface nanomaterials and further understanding of surface chemistry.
Bottom-up approach to constructing low-dimensional nanostructures on surfaces with terminal alkynes has drawn great interest because of its potential applications in fabricating advanced functional nanomaterials. The diversity of the achieved products manifests rich chemistry of terminal alkynes and hence careful linking strategies and proper controlling methodologies are required for selective preparations of high-quality target nanoarchitectures. This review summarizes various on-surface linking strategies for terminal alkynes, including non-bonding interactions as well as organometallic and covalent bonds, and presents examples to show effective control of surface assemblies and reactions of terminal alkynes by variations of the precursor structures, substrates and activation modes. Systematic studies of the on-surface linkage of terminal alkynes may help efficient and predictable preparations of surface nanomaterials and further understanding of surface chemistry.
2017, 28(8): 1640-1652
doi: 10.1016/j.cclet.2017.05.008
Abstract:
Capillary electrophoresis-mass spectrometry (CE-MS) is a powerful separation and analytical technique in the field of analytical chemistry. This review provides an update of instrumentation developments in the methodology of CE-MS systems. A selection of relevant articles covers the literatures published from Jan. 2013 to Feb. 2017. Special attentions were paid to the sample injection and ionization processes. Applications of these CE-MS systems were also introduced through representative examples. General conclusions and perspectives were given at the last.
Capillary electrophoresis-mass spectrometry (CE-MS) is a powerful separation and analytical technique in the field of analytical chemistry. This review provides an update of instrumentation developments in the methodology of CE-MS systems. A selection of relevant articles covers the literatures published from Jan. 2013 to Feb. 2017. Special attentions were paid to the sample injection and ionization processes. Applications of these CE-MS systems were also introduced through representative examples. General conclusions and perspectives were given at the last.
2017, 28(8): 1653-1658
doi: 10.1016/j.cclet.2017.04.025
Abstract:
Solvothermal reaction of 3-aminoisonicotinic acid (Haina) and Cu(NO3)2·2.5H2O gave a novel twodimensional (2D) microporous metal-organic framework, [Cu(aina)2(DMF)]·DMF (1, DMF=N, N-dimethylformamide). Single-crystal X-ray crystallographic study of compound 1 revealed that Cu(Ⅱ) ions are linked by aina- ligands forming square grid-like layers, which stack together via multiple hydrogen bonding interactions. The solvent-free framework of 1a displayed considerable porosity (void=46.5%) with one-dimensional (1D) open channels (4.7 Å×4.8 Å) functionalized by amino groups. Gas sorption measurements of 1 revealed selective carbon dioxide (CO2) and acetylene (C2H2) adsorption over methane (CH4) and nitrogen (N2) at ambient temperature.
Solvothermal reaction of 3-aminoisonicotinic acid (Haina) and Cu(NO3)2·2.5H2O gave a novel twodimensional (2D) microporous metal-organic framework, [Cu(aina)2(DMF)]·DMF (1, DMF=N, N-dimethylformamide). Single-crystal X-ray crystallographic study of compound 1 revealed that Cu(Ⅱ) ions are linked by aina- ligands forming square grid-like layers, which stack together via multiple hydrogen bonding interactions. The solvent-free framework of 1a displayed considerable porosity (void=46.5%) with one-dimensional (1D) open channels (4.7 Å×4.8 Å) functionalized by amino groups. Gas sorption measurements of 1 revealed selective carbon dioxide (CO2) and acetylene (C2H2) adsorption over methane (CH4) and nitrogen (N2) at ambient temperature.
2017, 28(8): 1659-1662
doi: 10.1016/j.cclet.2017.06.006
Abstract:
Foldamers 1-4 incorporating different terminal substituents have been designed and synthesized for binding halide anions. 1H NMR titration experiments carried out in DMSO-d6/CDCl3 (15/85, v/v) demonstrated that the short oligo(aryltriazole)s backbone 1 could not bind halide anions unless that amide H-bond donors were incorporated at the termini of the oligomer. Terminal substituents on oligo(aryltriazoleamide)s foldamers 2-4 display a considerable influence on the binding affinities of the foldamers for halide anions. Large steric hindrance of the terminal substituents was found to be unfavorable for binding halide anions, but aromatic π-π interactions between two terminal substituents are capable of stabilizing the conformation of foldamers thus giving rise to an enhancement in the binding strengths. However, the terminal substituents were found to hardly affect the binding selectivity in the studied cases.
Foldamers 1-4 incorporating different terminal substituents have been designed and synthesized for binding halide anions. 1H NMR titration experiments carried out in DMSO-d6/CDCl3 (15/85, v/v) demonstrated that the short oligo(aryltriazole)s backbone 1 could not bind halide anions unless that amide H-bond donors were incorporated at the termini of the oligomer. Terminal substituents on oligo(aryltriazoleamide)s foldamers 2-4 display a considerable influence on the binding affinities of the foldamers for halide anions. Large steric hindrance of the terminal substituents was found to be unfavorable for binding halide anions, but aromatic π-π interactions between two terminal substituents are capable of stabilizing the conformation of foldamers thus giving rise to an enhancement in the binding strengths. However, the terminal substituents were found to hardly affect the binding selectivity in the studied cases.
2017, 28(8): 1663-1669
doi: 10.1016/j.cclet.2017.05.021
Abstract:
The macroscopic alignment of conjugated polymers with low grain boundary is essential to carrier transport. During film forming process, the match between contact line receding velocity and the critical alignment velocity is essential to get the alignment polymer film. In this paper, the contact line receding velocity of a D-A conjugated polymer film, isoindigo and bithiophene (ⅡDDT-C3), was adjusted by solvent vapor content and film-formation temperature. Only when solvent vapor content was 0.3 mL and the film-formation temperature was 90℃, the contact line receding velocity was in accordance with the critical alignment velocity, and the highest degree of alignment was attained in the ⅡDDT-C3 film, with the dichroic ratio up to 4.08. Fibers were aligned parallel with the direction of the contact line receding and the molecules of ⅡDDT-C3 adopted an edge-on orientation with the backbone parallel with the direction of fiber long axis. The π-π stacking distance between adjacent molecules was 3.63 Å.
The macroscopic alignment of conjugated polymers with low grain boundary is essential to carrier transport. During film forming process, the match between contact line receding velocity and the critical alignment velocity is essential to get the alignment polymer film. In this paper, the contact line receding velocity of a D-A conjugated polymer film, isoindigo and bithiophene (ⅡDDT-C3), was adjusted by solvent vapor content and film-formation temperature. Only when solvent vapor content was 0.3 mL and the film-formation temperature was 90℃, the contact line receding velocity was in accordance with the critical alignment velocity, and the highest degree of alignment was attained in the ⅡDDT-C3 film, with the dichroic ratio up to 4.08. Fibers were aligned parallel with the direction of the contact line receding and the molecules of ⅡDDT-C3 adopted an edge-on orientation with the backbone parallel with the direction of fiber long axis. The π-π stacking distance between adjacent molecules was 3.63 Å.
2017, 28(8): 1670-1674
doi: 10.1016/j.cclet.2017.04.014
Abstract:
A new detection system consisted of a flame ionization detector (FID) and a sulfur chemiluminescence detector (SCD) was developed for sensitive and interference free determination of total sulfur in natural gas by non-separation gas chromatography. In this system, sulfur containing compounds and hydrocarbons were firstly burned in the FID using oxygen rich flame and converted to SO2, CO2 and H2O, respectively. The products from FID were transported into the SCD with hydrogen rich atmosphere wherein only SO2 could be reduced to SO and reacted with O3 to produce characteristic chemiluminescence. Therefore, the chemiluminescence of CO found in conventional SCD were eliminated because CO2 could not be reduced to CO under these conditions. The experimental parameters were systematically investigated. Limit of detection obtained by the proposed system is better than 0.5 μmol/mol for total sulfur and superior to those previously reported. The proposed method not only retains the advantages of the conventional SCD but also provides several unique advantages including no hydrocarbon interference, better stability, and easier calculation. The utility of this technique was demonstrated by the determination of total sulfur in real samples and two certified reference materials (GBW 06332 and GBW (E) 061320).
A new detection system consisted of a flame ionization detector (FID) and a sulfur chemiluminescence detector (SCD) was developed for sensitive and interference free determination of total sulfur in natural gas by non-separation gas chromatography. In this system, sulfur containing compounds and hydrocarbons were firstly burned in the FID using oxygen rich flame and converted to SO2, CO2 and H2O, respectively. The products from FID were transported into the SCD with hydrogen rich atmosphere wherein only SO2 could be reduced to SO and reacted with O3 to produce characteristic chemiluminescence. Therefore, the chemiluminescence of CO found in conventional SCD were eliminated because CO2 could not be reduced to CO under these conditions. The experimental parameters were systematically investigated. Limit of detection obtained by the proposed system is better than 0.5 μmol/mol for total sulfur and superior to those previously reported. The proposed method not only retains the advantages of the conventional SCD but also provides several unique advantages including no hydrocarbon interference, better stability, and easier calculation. The utility of this technique was demonstrated by the determination of total sulfur in real samples and two certified reference materials (GBW 06332 and GBW (E) 061320).
2017, 28(8): 1675-1680
doi: 10.1016/j.cclet.2017.05.001
Abstract:
A new facile fluorescence probing strategy, which was based on N-doped carbon dots (NCDs) and methyl parathion hydrolase (MPH), was developed for the determination of parathion-methyl (PM). The fluorescence intensity of NCDs-MPH system was proportional to PM concentration in the range of 2.38-73.78 μmol/L, with a detection limit of 0.338 μmol/L. Moreover, the present simple and facile method could be used to determine methyl parathion in environmental and agricultural samples successfully. Furthermore, the detection mechanism of this system is inner filter effect and molecular interactions between NCDs and p-nitrophenol, which is the hydrolysis product of PM catalyzed by methyl parathion hydrolase.
A new facile fluorescence probing strategy, which was based on N-doped carbon dots (NCDs) and methyl parathion hydrolase (MPH), was developed for the determination of parathion-methyl (PM). The fluorescence intensity of NCDs-MPH system was proportional to PM concentration in the range of 2.38-73.78 μmol/L, with a detection limit of 0.338 μmol/L. Moreover, the present simple and facile method could be used to determine methyl parathion in environmental and agricultural samples successfully. Furthermore, the detection mechanism of this system is inner filter effect and molecular interactions between NCDs and p-nitrophenol, which is the hydrolysis product of PM catalyzed by methyl parathion hydrolase.
2017, 28(8): 1681-1687
doi: 10.1016/j.cclet.2017.03.037
Abstract:
Two near-infrared (NIR) pH-activated heptamethine indocyanine probes with quaternary ammonium unit were designed and synthesized. The absorption and emission titrations indicate that cationic structure improves the cyanine dye's aqueous solubility and these two probes exhibit highly sensitive response to pH in acid condition. Their fluorescence intensities both gradually increase about 25-fold from pH 7.60 to 3.00 with pKa values of 4.72 and 4.45 respectively, which are suitable for studying acidic organelles in living cells. Moreover, their fluorescence intensities are linearly proportional to pH values in the range of 5.50-4.00. These results are probably attributed to the protonation of the indole nitrogen atoms, which are verified by 1H NMR spectra. Furthermore, these two probes can achieve real-time imaging of cellular pH and detection of pH in situ in living HeLa cells due to their excellent properties, including good reversibility, desirable photostability, high selectivity, low cytotoxicity and remarkable membrane permeability.
Two near-infrared (NIR) pH-activated heptamethine indocyanine probes with quaternary ammonium unit were designed and synthesized. The absorption and emission titrations indicate that cationic structure improves the cyanine dye's aqueous solubility and these two probes exhibit highly sensitive response to pH in acid condition. Their fluorescence intensities both gradually increase about 25-fold from pH 7.60 to 3.00 with pKa values of 4.72 and 4.45 respectively, which are suitable for studying acidic organelles in living cells. Moreover, their fluorescence intensities are linearly proportional to pH values in the range of 5.50-4.00. These results are probably attributed to the protonation of the indole nitrogen atoms, which are verified by 1H NMR spectra. Furthermore, these two probes can achieve real-time imaging of cellular pH and detection of pH in situ in living HeLa cells due to their excellent properties, including good reversibility, desirable photostability, high selectivity, low cytotoxicity and remarkable membrane permeability.
2017, 28(8): 1688-1692
doi: 10.1016/j.cclet.2017.05.013
Abstract:
1-epi-Castanospermine (5) was synthesized from readily available 2, 3, 4, 6-tetra-O-benzyl-1-deoxynojirimycin (11) in 9 steps and 21% overall yield, with selective debenzylation, Barbier reaction and reductive amination as the main reaction steps.
1-epi-Castanospermine (5) was synthesized from readily available 2, 3, 4, 6-tetra-O-benzyl-1-deoxynojirimycin (11) in 9 steps and 21% overall yield, with selective debenzylation, Barbier reaction and reductive amination as the main reaction steps.
2017, 28(8): 1693-1700
doi: 10.1016/j.cclet.2017.06.020
Abstract:
We herein described the design, synthesis and application of two recyclable benzyl-type fluorous tags with double fluorous chains. The benzyl-type fluorous tags were prepared in 3 steps from a commercially available fluorous alcohol. The glycosylation of the benzyl-type tags with imidate donors proceeded smoothly to provide the corresponding fluorous-tagged carbohydrates in good to excellent yields, which were readily purified by fluorous solid-phase extraction (FSPE). Efficient removal of the tags from tagtethered carbohydrates were conducted under the common catalytic hydrogenation condition and the initial benzyl-type fluorous tags could be regenerated via a 2-step simple procedure in 69%-93% yields. The utility of the new benzyl-fluorous tag was demonstrated via the FSPE-assisted synthesis of oligosaccharides Gb3.
We herein described the design, synthesis and application of two recyclable benzyl-type fluorous tags with double fluorous chains. The benzyl-type fluorous tags were prepared in 3 steps from a commercially available fluorous alcohol. The glycosylation of the benzyl-type tags with imidate donors proceeded smoothly to provide the corresponding fluorous-tagged carbohydrates in good to excellent yields, which were readily purified by fluorous solid-phase extraction (FSPE). Efficient removal of the tags from tagtethered carbohydrates were conducted under the common catalytic hydrogenation condition and the initial benzyl-type fluorous tags could be regenerated via a 2-step simple procedure in 69%-93% yields. The utility of the new benzyl-fluorous tag was demonstrated via the FSPE-assisted synthesis of oligosaccharides Gb3.
2017, 28(8): 1701-1704
doi: 10.1016/j.cclet.2017.06.016
Abstract:
A series of C-7 modified analogues of casuarine have been synthesized from sugar-derived nitrone and assayed against various glycosidases. Introduction of C-7 aminomethyl or amide group led to sharp decrease of the inhibitory activities.
A series of C-7 modified analogues of casuarine have been synthesized from sugar-derived nitrone and assayed against various glycosidases. Introduction of C-7 aminomethyl or amide group led to sharp decrease of the inhibitory activities.
2017, 28(8): 1705-1710
doi: 10.1016/j.cclet.2017.04.026
Abstract:
Four structurally unprecedented aconitane-type C19-diterpenoid alkaloid glycosides with isomeric arabinosyls, named aconicarmichosides A-D (1-4), were isolated from an aqueous extract of “fu zi”, the lateral roots of Aconitum carmichaelii. Their structures were determined as neoline 14-O-α-and 14-O-β-L-arabinopyranosides (1 and 2) and 14-O-α-and 14-O-β-L-arabinofuranosides (3 and 4), by spectroscopic and chemical methods including 2D NMR experiments and acid hydrolysis. Compounds 1-4 represent the first examples of glycosidic diterpenoid alkaloids.
Four structurally unprecedented aconitane-type C19-diterpenoid alkaloid glycosides with isomeric arabinosyls, named aconicarmichosides A-D (1-4), were isolated from an aqueous extract of “fu zi”, the lateral roots of Aconitum carmichaelii. Their structures were determined as neoline 14-O-α-and 14-O-β-L-arabinopyranosides (1 and 2) and 14-O-α-and 14-O-β-L-arabinofuranosides (3 and 4), by spectroscopic and chemical methods including 2D NMR experiments and acid hydrolysis. Compounds 1-4 represent the first examples of glycosidic diterpenoid alkaloids.
2017, 28(8): 1711-1715
doi: 10.1016/j.cclet.2017.04.023
Abstract:
Phytochemical investigation on the seeds of Caesalpinia sappan led to the isolation of five new cassanetype diterpenoids, named 11-oxo-phanginin A (1), caesalsappanins O-Q (2-4) and phanginin U (5), together with five known compounds. The structures of the new compounds were elucidated by extensive analysis of mass spectrometric and 1D and 2D NMR spectroscopic data. All the new compounds showed moderate cytotoxic effects on human breast cancer MCF-7 and human colon cancer HCT116 cell lines.
Phytochemical investigation on the seeds of Caesalpinia sappan led to the isolation of five new cassanetype diterpenoids, named 11-oxo-phanginin A (1), caesalsappanins O-Q (2-4) and phanginin U (5), together with five known compounds. The structures of the new compounds were elucidated by extensive analysis of mass spectrometric and 1D and 2D NMR spectroscopic data. All the new compounds showed moderate cytotoxic effects on human breast cancer MCF-7 and human colon cancer HCT116 cell lines.
2017, 28(8): 1716-1722
doi: 10.1016/j.cclet.2017.05.017
Abstract:
Phytochemical investigations from the roots of Cynanchum stauntonii led to obtain four new C21 steroidal glycosides (1-4) and one known compound stauntoside F (5). Their chemical structures were characterized by sophisticated analyses of IR, HRESI-TOF-MS, 1D, and 2D-NMR data, together with chemical methods, which showed interesting 13, 14:14, 15-disecopregnane-type skeleton or 14, 15-secopregnane-type skeleton C21 steroidal glycosides. Among them, compound 1 was determined to be glaucogenin C 3-O-β-D-glucopyranosyl-(1→4)-β-D-cymaropyranosyl-(1→4)-β-D-digitoxopyranosyl-(1→4)-β-D-thevetopyranoside. Compound 2 was characterized to be hirundigenin 3-O-α-L-diginopyr-anosyl-(1→4)-β-D-cymaropyranosyl-(1→4)-β-D-digitoxopyranosyl-(1→4)-β-D-3'-demethyl-theveto-pyranoside. Compound 3 was identified to be (14S, 16S, 20R)-14, 16-14, 20-15, 20-triepoxy-14, 15-secopregn-5-en-3-ol-3-O-α-L-cymaropyranosyl-(1→4)-β-D-digitoxopyranosyl-(1→4)-β-D-oleandropyranoside. Compound 4 was identified to be (14S, 16S, 20R)-14, 16-14, 20-15, 20-triepoxy-14, 15-secopregn-5-en-3-ol-3-O-α-L-cymaropyranosyl-(1→4)-β-D-cymaropyranosyl-(1→4)-β-D-digitoxopyranosyl-(1→4)-β-D-thevetopyranoside. Among them, compound 2 was hirundigenin type C21 steroidal glycoside that existed in nature as epimers due to the presence of 14-hemiketal hydroxyl group in its structure. In addition, the anti-inflammatory and cardiomyocyte protective effects of compounds 1-4 were evaluated.Wefound that they exhibited significant protective effects on hypoxia/reoxygenation induced cardiomyocyte injury, but did not showed obvious anti-inflammatory function.
Phytochemical investigations from the roots of Cynanchum stauntonii led to obtain four new C21 steroidal glycosides (1-4) and one known compound stauntoside F (5). Their chemical structures were characterized by sophisticated analyses of IR, HRESI-TOF-MS, 1D, and 2D-NMR data, together with chemical methods, which showed interesting 13, 14:14, 15-disecopregnane-type skeleton or 14, 15-secopregnane-type skeleton C21 steroidal glycosides. Among them, compound 1 was determined to be glaucogenin C 3-O-β-D-glucopyranosyl-(1→4)-β-D-cymaropyranosyl-(1→4)-β-D-digitoxopyranosyl-(1→4)-β-D-thevetopyranoside. Compound 2 was characterized to be hirundigenin 3-O-α-L-diginopyr-anosyl-(1→4)-β-D-cymaropyranosyl-(1→4)-β-D-digitoxopyranosyl-(1→4)-β-D-3'-demethyl-theveto-pyranoside. Compound 3 was identified to be (14S, 16S, 20R)-14, 16-14, 20-15, 20-triepoxy-14, 15-secopregn-5-en-3-ol-3-O-α-L-cymaropyranosyl-(1→4)-β-D-digitoxopyranosyl-(1→4)-β-D-oleandropyranoside. Compound 4 was identified to be (14S, 16S, 20R)-14, 16-14, 20-15, 20-triepoxy-14, 15-secopregn-5-en-3-ol-3-O-α-L-cymaropyranosyl-(1→4)-β-D-cymaropyranosyl-(1→4)-β-D-digitoxopyranosyl-(1→4)-β-D-thevetopyranoside. Among them, compound 2 was hirundigenin type C21 steroidal glycoside that existed in nature as epimers due to the presence of 14-hemiketal hydroxyl group in its structure. In addition, the anti-inflammatory and cardiomyocyte protective effects of compounds 1-4 were evaluated.Wefound that they exhibited significant protective effects on hypoxia/reoxygenation induced cardiomyocyte injury, but did not showed obvious anti-inflammatory function.
2017, 28(8): 1723-1726
doi: 10.1016/j.cclet.2017.05.016
Abstract:
1, 8-Naphthyridines (NAP) are biological important scaffolds in bioactive molecules design. By hybrid of NAP with neonicotinoid core structure, nine novel NAP derivatives were synthesized and subjected to insecticidal activities evaluation. Some of the compounds showed excellent insecticidal activity against cowpea aphids (Aphis craccivora) with LC50 values ranging from 0.011 mmol/L to 0.067 mmol/L. The results indicated that 1, 8-naphthyridine can be used as insecticidal structure for further modification.
1, 8-Naphthyridines (NAP) are biological important scaffolds in bioactive molecules design. By hybrid of NAP with neonicotinoid core structure, nine novel NAP derivatives were synthesized and subjected to insecticidal activities evaluation. Some of the compounds showed excellent insecticidal activity against cowpea aphids (Aphis craccivora) with LC50 values ranging from 0.011 mmol/L to 0.067 mmol/L. The results indicated that 1, 8-naphthyridine can be used as insecticidal structure for further modification.
2017, 28(8): 1727-1730
doi: 10.1016/j.cclet.2017.05.015
Abstract:
In order to discover new molecules with good insecticidal activities, a series of anthranilic diamides containing polyfluoroalkyl pyrazole were designed and synthesized, and their structures were characterized by 1H NMR and HRMS. Bioassays demonstrated that some of the title compound exhibited excellent insecticidal activities. The larvicidal activities of compound 8a, 8c, 8g, 8k and 8l against Mythimna separata Walker were 100% at 0.8 mg/L. The insecticidal activities of compound 8a, 8c, 8e, 8g, 8k and 8l against Plutella xylostella Linnaeus were 100% at 0.4 mg/L. Surprisingly compounds 8a and 8c still showed 100% larvicidal activities against Plutella xylostella Linnaeus at 0.08 mg/L comparable to the commercialized Chlorantraniliprole. The LC50 of compound 8a and 8c against M. separata is 0.048 and 0.043 mg/L respectively.
In order to discover new molecules with good insecticidal activities, a series of anthranilic diamides containing polyfluoroalkyl pyrazole were designed and synthesized, and their structures were characterized by 1H NMR and HRMS. Bioassays demonstrated that some of the title compound exhibited excellent insecticidal activities. The larvicidal activities of compound 8a, 8c, 8g, 8k and 8l against Mythimna separata Walker were 100% at 0.8 mg/L. The insecticidal activities of compound 8a, 8c, 8e, 8g, 8k and 8l against Plutella xylostella Linnaeus were 100% at 0.4 mg/L. Surprisingly compounds 8a and 8c still showed 100% larvicidal activities against Plutella xylostella Linnaeus at 0.08 mg/L comparable to the commercialized Chlorantraniliprole. The LC50 of compound 8a and 8c against M. separata is 0.048 and 0.043 mg/L respectively.
2017, 28(8): 1731-1736
doi: 10.1016/j.cclet.2017.04.021
Abstract:
Twenty-seven novel pyrazole carboxamides with diarylamine-modified scaffold were designed, synthesized and characterized in detail via 1H NMR, 13C NMR, IR and ESI-HRMS. Preliminary bioassays showed that some of the target compounds exhibited good antifungal activity against Rhizoctonia solani, Rhizoctonia cerealis and Sclerotinia sclerotiorum. Among them, compound 9c-7 exhibited the highest antifungal activities against R. solani, R. cerealis and S. sclerotiorum in vitro with IC50 values of 0.013, 1.608 and 1.874 μg/mL, respectively. Notably, compound 9c-7 still presented the highest fungicidal activities against R. solani in vivo with an IC50 value of 22.21 μg/mL. Molecular docking simulation results reveal that compound 9c-7 binds well to the hydrophobic pockets of the receptor protein succinate dehydrogenase. This study suggests that compound 9c-7 could act as a potential fungicide to be used for further optimization.
Twenty-seven novel pyrazole carboxamides with diarylamine-modified scaffold were designed, synthesized and characterized in detail via 1H NMR, 13C NMR, IR and ESI-HRMS. Preliminary bioassays showed that some of the target compounds exhibited good antifungal activity against Rhizoctonia solani, Rhizoctonia cerealis and Sclerotinia sclerotiorum. Among them, compound 9c-7 exhibited the highest antifungal activities against R. solani, R. cerealis and S. sclerotiorum in vitro with IC50 values of 0.013, 1.608 and 1.874 μg/mL, respectively. Notably, compound 9c-7 still presented the highest fungicidal activities against R. solani in vivo with an IC50 value of 22.21 μg/mL. Molecular docking simulation results reveal that compound 9c-7 binds well to the hydrophobic pockets of the receptor protein succinate dehydrogenase. This study suggests that compound 9c-7 could act as a potential fungicide to be used for further optimization.
Synthesis and biological evaluation of dihydrotriazine derivatives as potential antibacterial agents
2017, 28(8): 1737-1742
doi: 10.1016/j.cclet.2017.05.022
Abstract:
A series of 1, 4-dihydro-1, 3, 5-triazine derivatives were designed and synthesized and their antibacterial and antifungal activities were evaluated. Most of the synthesized compounds showed potent inhibition of several Gram-positive bacterial strains (including multidrug-resistant clinical isolates) and Gramnegative bacterial strains, with minimum inhibitory concentrations (MICs) in the range of 2.1-181.2 μmol/L. Compounds 7a and 7c presented the most potent inhibitory activities against Grampositive bacteria (e.g., Staphylococcus aureus 4220), Gram-negative bacteria (e.g., Escherichia coli 1924), and the fungus Candida albicans 7535, with MICs of 2.1 or 4.1 μmol/L. Especially, compound 7a was the most potent, with an MIC of 2.1 μmol/L against four multidrug-resistant, Gram-positive bacterial strains. The cytotoxic activity of the compound 7a, 7c and 7f was assessed in HepG2 cells, and the results suggest that 1, 4-dihydro-1, 3, 5-triazine derivatives bearing a 6-benzyloxynaphthalen moiety are interesting scaffolds for the development of novel antibacterial agents.
A series of 1, 4-dihydro-1, 3, 5-triazine derivatives were designed and synthesized and their antibacterial and antifungal activities were evaluated. Most of the synthesized compounds showed potent inhibition of several Gram-positive bacterial strains (including multidrug-resistant clinical isolates) and Gramnegative bacterial strains, with minimum inhibitory concentrations (MICs) in the range of 2.1-181.2 μmol/L. Compounds 7a and 7c presented the most potent inhibitory activities against Grampositive bacteria (e.g., Staphylococcus aureus 4220), Gram-negative bacteria (e.g., Escherichia coli 1924), and the fungus Candida albicans 7535, with MICs of 2.1 or 4.1 μmol/L. Especially, compound 7a was the most potent, with an MIC of 2.1 μmol/L against four multidrug-resistant, Gram-positive bacterial strains. The cytotoxic activity of the compound 7a, 7c and 7f was assessed in HepG2 cells, and the results suggest that 1, 4-dihydro-1, 3, 5-triazine derivatives bearing a 6-benzyloxynaphthalen moiety are interesting scaffolds for the development of novel antibacterial agents.
2017, 28(8): 1743-1745
doi: 10.1016/j.cclet.2017.05.002
Abstract:
A series of novel bridged-neonicotinoid analogues were designed and synthesized, which were constructed by starting material 8 with cyclopentenone or cyclohexenone in the presence of catalyst aluminium chloride. All of the compounds were characterized and confirmed by 1H NMR, 13C NMR, HRMS and IR. The bioassay tests showed that compounds 5 and 6a showed higher bioactivities than imidacloprid against Aphis craccivora.
A series of novel bridged-neonicotinoid analogues were designed and synthesized, which were constructed by starting material 8 with cyclopentenone or cyclohexenone in the presence of catalyst aluminium chloride. All of the compounds were characterized and confirmed by 1H NMR, 13C NMR, HRMS and IR. The bioassay tests showed that compounds 5 and 6a showed higher bioactivities than imidacloprid against Aphis craccivora.
2017, 28(8): 1746-1750
doi: 10.1016/j.cclet.2017.05.018
Abstract:
Formic acid (FA) dehydrogenation has attracted a lot of attentions since it is a convenient method for H2 production. In this work, we designed a self-supporting fuel cell system, in which H2 from FA is supplied into the fuel cell, and the exhaust heat from the fuel cell supported the FA dehydrogenation. In order to realize the system, we synthesized a highly active and selective homogeneous catalyst IrCp*Cl2bpym for FA dehydrogenation. The turnover frequency (TOF) of the catalyst for FA dehydrogenation is as high as 7150 h-1 at 50 ℃, and is up to 144, 000 h-1 at 90 ℃. The catalyst also shows excellent catalytic stability for FA dehydrogenation after several cycles of test. The conversion ratio of FA can achieve 93.2%, and no carbon monoxide is detected in the evolved gas. Therefore, the evolved gas could be applied in the proton exchange membrane fuel cell (PEMFC) directly. This is a potential technology for hydrogen storage and generation. The power density of the PEMFC driven by the evolved gas could approximate to that using pure hydrogen.
Formic acid (FA) dehydrogenation has attracted a lot of attentions since it is a convenient method for H2 production. In this work, we designed a self-supporting fuel cell system, in which H2 from FA is supplied into the fuel cell, and the exhaust heat from the fuel cell supported the FA dehydrogenation. In order to realize the system, we synthesized a highly active and selective homogeneous catalyst IrCp*Cl2bpym for FA dehydrogenation. The turnover frequency (TOF) of the catalyst for FA dehydrogenation is as high as 7150 h-1 at 50 ℃, and is up to 144, 000 h-1 at 90 ℃. The catalyst also shows excellent catalytic stability for FA dehydrogenation after several cycles of test. The conversion ratio of FA can achieve 93.2%, and no carbon monoxide is detected in the evolved gas. Therefore, the evolved gas could be applied in the proton exchange membrane fuel cell (PEMFC) directly. This is a potential technology for hydrogen storage and generation. The power density of the PEMFC driven by the evolved gas could approximate to that using pure hydrogen.
2017, 28(8): 1751-1754
doi: 10.1016/j.cclet.2017.03.039
Abstract:
In this work, an efficient and facile method for the preparation of 5-perfluoroalkylated uracils and uracil nucleosides through visible-light-mediated reaction has been developed. The reaction processes in high efficiency under mild reaction conditions and show broad substrate scope by employing commercial available perfluoroalkyl sources, thus demonstrates high potent application in life and medicinal science.
In this work, an efficient and facile method for the preparation of 5-perfluoroalkylated uracils and uracil nucleosides through visible-light-mediated reaction has been developed. The reaction processes in high efficiency under mild reaction conditions and show broad substrate scope by employing commercial available perfluoroalkyl sources, thus demonstrates high potent application in life and medicinal science.
2017, 28(8): 1755-1759
doi: 10.1016/j.cclet.2017.04.011
Abstract:
In this study, we report narrow-size distribution Zn2SnO4 (ZSO) nanoparticles, which are produced by low-temperature solution-processed used as the electron extraction layer (EEL) in the inverted polymer solar cells (i-PSCs). Moreover, poly[(9, 9-bis(3'-(N, N-dimethylamino)propyl)-2, 7-fluorene)-alt-2, 7-(9, 9-dioctylfluorene)] (PFN) is used to modify the surface properties of ZSO thin film. By using the ZSO NPs/PFN as the EEL, the i-PSCs fabricated by poly[4, 8-bis(2-ethylhexyloxyl)benzo[1, 2-b:4, 5-b'] dithio-phene-2, 6-diyl-altethylhexyl-3-fluorothithieno [3, 4-b]thiophene-2-carboxylate-4, 6-diyl] (PTB7) blended with (6, 6)-phenyl-C71-butyric acid methylester (PC71BM) bulk heterojunction (BHJ) composite, exhibits a power conversion efficiency (PCE) of 8.44%, which is nearly 10% enhancement as compared with that of 7.75% observed from the i-PSCs by PTB7:PC71BM BHJ composite using the ZnO/PFN EEL. The enhanced PCE is originated from improved interfacial contact between the EEL with BHJ active layer and good energy level alignment between BHJ active layer and the EEL. Our results indicate that we provide a simple way to boost efficiency of i-PSCs.
In this study, we report narrow-size distribution Zn2SnO4 (ZSO) nanoparticles, which are produced by low-temperature solution-processed used as the electron extraction layer (EEL) in the inverted polymer solar cells (i-PSCs). Moreover, poly[(9, 9-bis(3'-(N, N-dimethylamino)propyl)-2, 7-fluorene)-alt-2, 7-(9, 9-dioctylfluorene)] (PFN) is used to modify the surface properties of ZSO thin film. By using the ZSO NPs/PFN as the EEL, the i-PSCs fabricated by poly[4, 8-bis(2-ethylhexyloxyl)benzo[1, 2-b:4, 5-b'] dithio-phene-2, 6-diyl-altethylhexyl-3-fluorothithieno [3, 4-b]thiophene-2-carboxylate-4, 6-diyl] (PTB7) blended with (6, 6)-phenyl-C71-butyric acid methylester (PC71BM) bulk heterojunction (BHJ) composite, exhibits a power conversion efficiency (PCE) of 8.44%, which is nearly 10% enhancement as compared with that of 7.75% observed from the i-PSCs by PTB7:PC71BM BHJ composite using the ZnO/PFN EEL. The enhanced PCE is originated from improved interfacial contact between the EEL with BHJ active layer and good energy level alignment between BHJ active layer and the EEL. Our results indicate that we provide a simple way to boost efficiency of i-PSCs.
2017, 28(8): 1760-1766
doi: 10.1016/j.cclet.2017.04.012
Abstract:
The interaction of Co with ceria thin films and its influence on the sintering behavior of Au were investigated by scanning tunneling microscopy (STM), synchrotron radiation photoemission spectroscopy (SRPES) and X-ray photoelectron spectroscopy (XPS). The strong interaction between Co and CeO2(111) leads to oxidation of Co to Co2+ at 300 K, accompanied by partial reduction of ceria surface at low Co coverages. Subsequent Co deposition results in an increasing fraction of metallic Co. Annealing to high temperatures induces Co2+ ions diffuse into the CeO2 film, while the small metallic Co islands agglomerate into larger ones. The bimetallic Co-Au particles were prepared by deposition of Au on the existing Co particles on ceria surfaces. The sintering behavior of Co-Au bimetallic surfaces is found to be highly determined by the stoichiometry of ceria supports. The addition of Co to the Au/CeO2 surface suppresses the sintering of Au particles at high temperatures in comparison with that of pure Au particles. However, Au particles are less stable on the Co/CeO1.82 layer than on CeO1.82 surface.
The interaction of Co with ceria thin films and its influence on the sintering behavior of Au were investigated by scanning tunneling microscopy (STM), synchrotron radiation photoemission spectroscopy (SRPES) and X-ray photoelectron spectroscopy (XPS). The strong interaction between Co and CeO2(111) leads to oxidation of Co to Co2+ at 300 K, accompanied by partial reduction of ceria surface at low Co coverages. Subsequent Co deposition results in an increasing fraction of metallic Co. Annealing to high temperatures induces Co2+ ions diffuse into the CeO2 film, while the small metallic Co islands agglomerate into larger ones. The bimetallic Co-Au particles were prepared by deposition of Au on the existing Co particles on ceria surfaces. The sintering behavior of Co-Au bimetallic surfaces is found to be highly determined by the stoichiometry of ceria supports. The addition of Co to the Au/CeO2 surface suppresses the sintering of Au particles at high temperatures in comparison with that of pure Au particles. However, Au particles are less stable on the Co/CeO1.82 layer than on CeO1.82 surface.
2017, 28(8): 1767-1772
doi: 10.1016/j.cclet.2017.04.029
Abstract:
NaY zeolite functionalized by sulfamic acid/Cu(OAc)2 [NaY/SA/Cu(Ⅱ)] was synthesized and used as a new, efficient and recyclable catalyst for preparation of formamides. This novel organic-inorganic hybrid catalyst was characterized by several techniques such as FT-IR, XRD, SEM, EDX and TG analysis. Chemoselectivity, easy procedure, excellent yields, very short reaction times, solvent-free and mild reaction conditions are some benefits of this new protocol.
NaY zeolite functionalized by sulfamic acid/Cu(OAc)2 [NaY/SA/Cu(Ⅱ)] was synthesized and used as a new, efficient and recyclable catalyst for preparation of formamides. This novel organic-inorganic hybrid catalyst was characterized by several techniques such as FT-IR, XRD, SEM, EDX and TG analysis. Chemoselectivity, easy procedure, excellent yields, very short reaction times, solvent-free and mild reaction conditions are some benefits of this new protocol.
2017, 28(8): 1773-1779
doi: 10.1016/j.cclet.2017.04.005
Abstract:
The new organic-inorganic compound, [C6H7N2O2]3TeCl5·2Cl was synthesized and its structure was determined at room temperature in the triclinic system(P-1) with the following parameters: a=10.5330 (11)Å, b=10.6663(11)Å, c=15.9751(16)Å, α=82.090(2)°, β=71.193(2)°, γ=68.284(2)° and Z=2. The final cycle of refinement led to R=0.057 and Rw=0.149. The crystal structure was stabilized by an extensive network of N-H…Cl and non-classical C-H…Cl hydrogen bonds between the cation and the anionic group. Several thermal analysis techniques such as thermogravimetric analysis, differential scanning calorimetric analysis and evolved gas analysis were used. We used isoconversional kinetics methods to determine the kinetics parameters. We observe that the decomposition of [C6H7N2O2]3TeCl5·2Cl entails the formation hydrochloric acid of nitroaniline as volatiles. The infrared spectra were recorded in the 4000-400 cm-1 frequency region. The Raman spectra were recorded in the external region of the anionic sublattice vibration 50-1500 cm-1. The optical band gap was calculated from the UV-Vis absorbance spectra using classical Tauc relation which was found to be 3.12 and 3.67 eV.
The new organic-inorganic compound, [C6H7N2O2]3TeCl5·2Cl was synthesized and its structure was determined at room temperature in the triclinic system(P-1) with the following parameters: a=10.5330 (11)Å, b=10.6663(11)Å, c=15.9751(16)Å, α=82.090(2)°, β=71.193(2)°, γ=68.284(2)° and Z=2. The final cycle of refinement led to R=0.057 and Rw=0.149. The crystal structure was stabilized by an extensive network of N-H…Cl and non-classical C-H…Cl hydrogen bonds between the cation and the anionic group. Several thermal analysis techniques such as thermogravimetric analysis, differential scanning calorimetric analysis and evolved gas analysis were used. We used isoconversional kinetics methods to determine the kinetics parameters. We observe that the decomposition of [C6H7N2O2]3TeCl5·2Cl entails the formation hydrochloric acid of nitroaniline as volatiles. The infrared spectra were recorded in the 4000-400 cm-1 frequency region. The Raman spectra were recorded in the external region of the anionic sublattice vibration 50-1500 cm-1. The optical band gap was calculated from the UV-Vis absorbance spectra using classical Tauc relation which was found to be 3.12 and 3.67 eV.
Synthesis of trifluoromethyl-/cyclopropyl-substituted 2-isoxazolines by DBU-promoted domino reaction
2017, 28(8): 1780-1783
doi: 10.1016/j.cclet.2017.03.031
Abstract:
NTrifluoromethyl and cyclopropyl substituted 2-isoxazolines were synthesized via a DBU-promoted domino reaction of β-trifluoromethyl-/β-cyclopropyl-substituted enones with hydroxylamine. The domino reaction consists of a Michael addition and the followed cyclization. A wide range of 3-substituted 5-cyclopropyl-5-trifluoromethyl-2-isoxazolines were obtained in good to excellent yields under mild reaction conditions. The method could also apply to other trifluoromethyl-substituted enones.
NTrifluoromethyl and cyclopropyl substituted 2-isoxazolines were synthesized via a DBU-promoted domino reaction of β-trifluoromethyl-/β-cyclopropyl-substituted enones with hydroxylamine. The domino reaction consists of a Michael addition and the followed cyclization. A wide range of 3-substituted 5-cyclopropyl-5-trifluoromethyl-2-isoxazolines were obtained in good to excellent yields under mild reaction conditions. The method could also apply to other trifluoromethyl-substituted enones.
2017, 28(8): 1784-1787
doi: 10.1016/j.cclet.2017.04.006
Abstract:
A series of 1, 3-bis(2-alkyltetrazol-5-yl)triazenes have been synthesized in high yields by treatment of sodium nitrite and hydrochloric acid with substituted-5-aminotetrazoles. All compounds were fully characterized using IR spectroscopy, 1H NMR and 13C NMR spectroscopy and high resolution mass spectrometer (HRMS). Most of these triazenes exhibit good detonation performance comparable with TNT and low melting points ranging from 81 ℃ to 106 ℃, which are suitable for melt-cast explosives. Among these compounds, 1, 3-bis(2-azidoethyltetrazol-5-yl)triazene (2g) displays a low melting point (106 ℃), moderate onset decomposition temperature (183 ℃) and good detonation performance (D: 7087 m/s; P: 17.6 GPa).
A series of 1, 3-bis(2-alkyltetrazol-5-yl)triazenes have been synthesized in high yields by treatment of sodium nitrite and hydrochloric acid with substituted-5-aminotetrazoles. All compounds were fully characterized using IR spectroscopy, 1H NMR and 13C NMR spectroscopy and high resolution mass spectrometer (HRMS). Most of these triazenes exhibit good detonation performance comparable with TNT and low melting points ranging from 81 ℃ to 106 ℃, which are suitable for melt-cast explosives. Among these compounds, 1, 3-bis(2-azidoethyltetrazol-5-yl)triazene (2g) displays a low melting point (106 ℃), moderate onset decomposition temperature (183 ℃) and good detonation performance (D: 7087 m/s; P: 17.6 GPa).
2017, 28(8): 1788-1792
doi: 10.1016/j.cclet.2017.03.032
Abstract:
A model study leading to the preparation of the unique tricyclo [6.2.1.0] undecane BCD ring systems of aconitine is described. The synthesis features an unprecedented diastereoselective oxidative dearomatization/dimerization/retro-DA/IMDA cascade reaction and a highly efficient Wagner-Meerwein rearrangement.
A model study leading to the preparation of the unique tricyclo [6.2.1.0] undecane BCD ring systems of aconitine is described. The synthesis features an unprecedented diastereoselective oxidative dearomatization/dimerization/retro-DA/IMDA cascade reaction and a highly efficient Wagner-Meerwein rearrangement.
2017, 28(8): 1793-1797
doi: 10.1016/j.cclet.2017.04.017
Abstract:
An intramolecular organocatalytic enantioselective aza-Michael reaction of carbamates, sulfonamides and acetamides to α, β-unsaturated ketones was developed. This process is promoted by 9-amino-9-deoxy-epi-quinine and diphenyl hydrogen phosphate to afford a straightforward and expeditious synthesis of several synthetically useful five-and six-membered heterocycles with excellent enantioselectivity (92%-97.5% ee) and very good yields (up to 99%).
An intramolecular organocatalytic enantioselective aza-Michael reaction of carbamates, sulfonamides and acetamides to α, β-unsaturated ketones was developed. This process is promoted by 9-amino-9-deoxy-epi-quinine and diphenyl hydrogen phosphate to afford a straightforward and expeditious synthesis of several synthetically useful five-and six-membered heterocycles with excellent enantioselectivity (92%-97.5% ee) and very good yields (up to 99%).
