2016 Volume 27 Issue 4
2016, 27(4): 487-491
Abstract:
The integration of multiscale and multicomponent of molecules and nanoparticles into thin films for applications requires the abilities of controlled their processing and assembly, which has been an great challenge because of the difficulty in manipulating the various materials such as small molecules, complexes, polymers, and inorganic nanomaterials through synergetic combinations of chemical or physical fabrications. Eletropolymerization is of great significance to fabricate polymeric film materials straight on the conductive substrates with tunable morphologies and thicknesses. However, unlimited electrochemical reactions(polymerization) have been usually leading to disadvantageous in ill-defined structure and highly doped state. Thanks to finding of exceptional electrochemical reaction (oligomerization) of N-alkylcarbazole, electrochemical layer by layer assembly has emerged as a promising strategy for a wide library of applications. The capability of this strategy can manipulate various molecules and nanoparticles into the scale and component controllable thin films. Unlike other electropolymerizable precursors such as aniline and thiophene, the resulting di-N-alkylcarbazole is transparent in the visible light region and thus does not impair the intrinsic properties of the components in the film. This account highlights of the typical findings in investigating both single- and multi-components thin films as a forum for discussing new opportunities in exploiting novel designs and applications of optical thin films.
The integration of multiscale and multicomponent of molecules and nanoparticles into thin films for applications requires the abilities of controlled their processing and assembly, which has been an great challenge because of the difficulty in manipulating the various materials such as small molecules, complexes, polymers, and inorganic nanomaterials through synergetic combinations of chemical or physical fabrications. Eletropolymerization is of great significance to fabricate polymeric film materials straight on the conductive substrates with tunable morphologies and thicknesses. However, unlimited electrochemical reactions(polymerization) have been usually leading to disadvantageous in ill-defined structure and highly doped state. Thanks to finding of exceptional electrochemical reaction (oligomerization) of N-alkylcarbazole, electrochemical layer by layer assembly has emerged as a promising strategy for a wide library of applications. The capability of this strategy can manipulate various molecules and nanoparticles into the scale and component controllable thin films. Unlike other electropolymerizable precursors such as aniline and thiophene, the resulting di-N-alkylcarbazole is transparent in the visible light region and thus does not impair the intrinsic properties of the components in the film. This account highlights of the typical findings in investigating both single- and multi-components thin films as a forum for discussing new opportunities in exploiting novel designs and applications of optical thin films.
2016, 27(4): 492-496
Abstract:
In(BTC)(phen)(H2O) nanocrystals with controllable morphology and size were successfully obtained by solvothermal method. Hierarchical straw-sheaf-like architectures, nanorods and elongated hexagons have been synthesized by varying the volume ratio of DMF:H2O:C2H5OH. Phase-pure In2O3 nanocrystals were obtained by the calcination of the precursors without significant alteration of themorphology. The products were characterized by PXRD, SEM, TEM, TGA, IR and gas adsorption measurements. The photocatalytic effect was investigated for the In2O3 nanocrystals with different morphology on the degradation of rhodamine B (RhB) and it was found that the nanorods exhibited the best photocatalytic activity, which shows the degradation efficiency of 94% for 8 h. The results showed that the photocatalytic activity increased with the increase of BET surface area and pore volume.
In(BTC)(phen)(H2O) nanocrystals with controllable morphology and size were successfully obtained by solvothermal method. Hierarchical straw-sheaf-like architectures, nanorods and elongated hexagons have been synthesized by varying the volume ratio of DMF:H2O:C2H5OH. Phase-pure In2O3 nanocrystals were obtained by the calcination of the precursors without significant alteration of themorphology. The products were characterized by PXRD, SEM, TEM, TGA, IR and gas adsorption measurements. The photocatalytic effect was investigated for the In2O3 nanocrystals with different morphology on the degradation of rhodamine B (RhB) and it was found that the nanorods exhibited the best photocatalytic activity, which shows the degradation efficiency of 94% for 8 h. The results showed that the photocatalytic activity increased with the increase of BET surface area and pore volume.
2016, 27(4): 497-501
Abstract:
A Cd-containing metal-organic framework (CdL), formula as {[Cd3(L)2(H2O)6]·1.5DMF}, has been synthesized under solvothermal condition by the reaction of 4, 4', 4"-(methylsilanetriyl)tribenzoic acid (H3L) and Cd2+ ion. Single-crystal X-ray diffraction reveals that CdL displays a three-dimensional framework with 2-fold interpenetration and DMF molecules locate in the void space of the channels. A topological analysis of the framework indicates CdL is a 3, 4-connected pto net. The photoluminescence properties of CdL are systematically studied in detail. Impressively, CdL shows excellent detection performance towards Fe3+ ion and acetone in the sensing experiments, which undoubtedly demonstrates the great potential of CdL as a highly selective multi-responsive luminescent sensor for the detection of organic solvents and metal ions.
A Cd-containing metal-organic framework (CdL), formula as {[Cd3(L)2(H2O)6]·1.5DMF}, has been synthesized under solvothermal condition by the reaction of 4, 4', 4"-(methylsilanetriyl)tribenzoic acid (H3L) and Cd2+ ion. Single-crystal X-ray diffraction reveals that CdL displays a three-dimensional framework with 2-fold interpenetration and DMF molecules locate in the void space of the channels. A topological analysis of the framework indicates CdL is a 3, 4-connected pto net. The photoluminescence properties of CdL are systematically studied in detail. Impressively, CdL shows excellent detection performance towards Fe3+ ion and acetone in the sensing experiments, which undoubtedly demonstrates the great potential of CdL as a highly selective multi-responsive luminescent sensor for the detection of organic solvents and metal ions.
2016, 27(4): 502-506
Abstract:
Two new metal-organic frameworks (MOFs),[Cu2(H2O)2(BCPIA)] (BUT-20) and (Me2NH2)[In(BCPIA)] (BUT-21) were designed and synthesized through the solvothermal reaction between a newly created desymmetric 4-connected ligand, 5-(2, 6-bis(4-carboxyphenyl)pyridin-4-yl)isophthalic acid (H4BCPIA) and Cu(NO3)2·2.5H2O or In(NO3)3·5H2O, respectively, and characterized by single-crystal and powder Xray diffraction, thermogravimetric analysis, infrared spectroscopy, and elemental analysis. The two MOFs have three-dimensional structures, in which both the BCPIA4-ligand and metal-containing entities, Cu2(COO)4(H2O)2 and In(COO)4 act as 4-connected nodes. However, different linkage configurations of the two metal-containing nodes, quadrilateral Cu2(COO)4(H2O)2 and tetrahedral In(COO)4, lead to distinct structural networks of BUT-20 and -21, with Nbo and Unc topologies, respectively.
Two new metal-organic frameworks (MOFs),[Cu2(H2O)2(BCPIA)] (BUT-20) and (Me2NH2)[In(BCPIA)] (BUT-21) were designed and synthesized through the solvothermal reaction between a newly created desymmetric 4-connected ligand, 5-(2, 6-bis(4-carboxyphenyl)pyridin-4-yl)isophthalic acid (H4BCPIA) and Cu(NO3)2·2.5H2O or In(NO3)3·5H2O, respectively, and characterized by single-crystal and powder Xray diffraction, thermogravimetric analysis, infrared spectroscopy, and elemental analysis. The two MOFs have three-dimensional structures, in which both the BCPIA4-ligand and metal-containing entities, Cu2(COO)4(H2O)2 and In(COO)4 act as 4-connected nodes. However, different linkage configurations of the two metal-containing nodes, quadrilateral Cu2(COO)4(H2O)2 and tetrahedral In(COO)4, lead to distinct structural networks of BUT-20 and -21, with Nbo and Unc topologies, respectively.
2016, 27(4): 507-510
Abstract:
Chemical doping of nickel hydroxide with other cations (e.g. Al3+) is an efficient way to enhance its electrochemical capacitive performances. Herein, a simple cation-anion (Ni2+ and AlO2-) double hydrolysis method was developed toward the synthesis of nickel-aluminum (Ni-Al) composite hydroxides. The obtained composite hydroxides possesses a porous structure, large surface area (121 m2/g) and homogeneous element distribution. The electrochemical test shows that the obtained composite hydroxides exhibits a superior supercapacitive performances (specific capacitance of 1670 F/g and rate capability of 87% from 0.5 A/g to 20 A/g) to doping-free nickel hydroxide (specific capacitance of 1227 F/g and rate capability of 47% from 0.5 A/g to 20 A/g). Moreover, the galvanostatic charge/discharge test displays that after 2000 cycles at large current density of 10 A/g, the composite hydroxides achieves a high capacitance retention of 98%, indicative of an excellent electrochemical cycleability.
Chemical doping of nickel hydroxide with other cations (e.g. Al3+) is an efficient way to enhance its electrochemical capacitive performances. Herein, a simple cation-anion (Ni2+ and AlO2-) double hydrolysis method was developed toward the synthesis of nickel-aluminum (Ni-Al) composite hydroxides. The obtained composite hydroxides possesses a porous structure, large surface area (121 m2/g) and homogeneous element distribution. The electrochemical test shows that the obtained composite hydroxides exhibits a superior supercapacitive performances (specific capacitance of 1670 F/g and rate capability of 87% from 0.5 A/g to 20 A/g) to doping-free nickel hydroxide (specific capacitance of 1227 F/g and rate capability of 47% from 0.5 A/g to 20 A/g). Moreover, the galvanostatic charge/discharge test displays that after 2000 cycles at large current density of 10 A/g, the composite hydroxides achieves a high capacitance retention of 98%, indicative of an excellent electrochemical cycleability.
2016, 27(4): 511-517
Abstract:
Macroporous polystyrene microsphere/graphene oxide (PS/GO) composite monolith was first prepared using Pickering emulsion droplets as the soft template. The Pickering emulsion was stabilized by PS/GO composite particles in-situ formed in an acidic water phase. With the evaporation of water and the oil phase (octane), the Pickering emulsion droplets agglomerated and combined with each other, forming a three-dimensional macroporous PS/GO composite matrix with excellent mechanical strength. The size of the macrospores ranged from 4 μm to 20 μm. The macroporous PS/GO composite monolith exhibited high adsorption capacity for tetracycline (TC) in an aqueous solution at pH 4-6. The maximum adsorption capacity reached 197.9 mg g-1 at pH 6. The adsorption behaviour of TC fitted well with the Langmuir model and pseudo-second-order kinetic model. This work offers a simple and efficient approach to fabricate macroporous GO-based monolith with high strength and adsorption ability for organic pollutants.
Macroporous polystyrene microsphere/graphene oxide (PS/GO) composite monolith was first prepared using Pickering emulsion droplets as the soft template. The Pickering emulsion was stabilized by PS/GO composite particles in-situ formed in an acidic water phase. With the evaporation of water and the oil phase (octane), the Pickering emulsion droplets agglomerated and combined with each other, forming a three-dimensional macroporous PS/GO composite matrix with excellent mechanical strength. The size of the macrospores ranged from 4 μm to 20 μm. The macroporous PS/GO composite monolith exhibited high adsorption capacity for tetracycline (TC) in an aqueous solution at pH 4-6. The maximum adsorption capacity reached 197.9 mg g-1 at pH 6. The adsorption behaviour of TC fitted well with the Langmuir model and pseudo-second-order kinetic model. This work offers a simple and efficient approach to fabricate macroporous GO-based monolith with high strength and adsorption ability for organic pollutants.
2016, 27(4): 518-522
Abstract:
Infinite coordination polymers are recognized as excellent platform for functionalization. Dithienylethene motifs, which are one of the most attractive functional moieties, were incorporated into an infinite coordination polymer, to deliver a "smart" porous material that can response to external stimuli. The obtained dithienylethene-based infinite coordination polymers (named Cu-DTEDBA) share the advantages of both infinite coordination polymers (porosity and stability) and dithienylethene motifs (photochromism). The physical and chemical properties of Cu-DTEDBA were characterized by FTIR, TEM, SEM, XRD, TGA, UV-vis, EDX and BET. Moreover, the combination of dithienylethene and infinite coordination polymers gives rise to a synergistic effect, which induces functional behaviors of ammonia sensor applications. Both open and closed forms of Cu-DTEDBA exhibit distinct colorimetric change upon exposure to gaseous ammonia, which is not observed in dithienylethene free molecules.
Infinite coordination polymers are recognized as excellent platform for functionalization. Dithienylethene motifs, which are one of the most attractive functional moieties, were incorporated into an infinite coordination polymer, to deliver a "smart" porous material that can response to external stimuli. The obtained dithienylethene-based infinite coordination polymers (named Cu-DTEDBA) share the advantages of both infinite coordination polymers (porosity and stability) and dithienylethene motifs (photochromism). The physical and chemical properties of Cu-DTEDBA were characterized by FTIR, TEM, SEM, XRD, TGA, UV-vis, EDX and BET. Moreover, the combination of dithienylethene and infinite coordination polymers gives rise to a synergistic effect, which induces functional behaviors of ammonia sensor applications. Both open and closed forms of Cu-DTEDBA exhibit distinct colorimetric change upon exposure to gaseous ammonia, which is not observed in dithienylethene free molecules.
2016, 27(4): 523-526
Abstract:
Field-effect transistors (FETs) of three diketopyrrolopyrroles (DPP)-based small molecules, 3, 6-bis(5-phenylthiophene-2-yl)-2, 5-bis(2-ethylhexyl)pyrrolo[3, 4-c]pyrrole-1, 4-dione (PDPPP), 3, 6-bis(5-(4-fluorophenyl) thiophene-2-yl)-2, 5-bis(2-ethylhexyl)pyrrolo[3, 4-c]pyrrole-1, 4-dione (FPDPPPF) and 3, 6-bis(5-(4-n-butylphenyl)thiophene-2-yl)-2, 5-bis(2-ethylhexyl)pyrrolo[3, 4-c]pyrrole-1, 4-dione (BuPDPPPBu), have been studied in this work. Well aligned crystals of the three molecules were grown from para-xylene by droplet-pinned crystallizationmethod. FETs based on these aligned crystals exhibit a holemobility up to 0.19 cm2 V-1 s-1 and electronmobility up to 0.008 cm2 V-1 s-1. The achieved hole mobility is of the same order of magnitude as reported highest hole mobility for DPP-based small molecules, but it is much lower than that of the high-performanceDPP-based polymers. The relative lowmobility ismainly attributed to the rough crystal surfaces with steps and, thus, non-smooth charge transport channels at the interfaces between the crystals and the dielectrics. This work has implications for understanding the low charge mobility of DPP-based small molecules.
Field-effect transistors (FETs) of three diketopyrrolopyrroles (DPP)-based small molecules, 3, 6-bis(5-phenylthiophene-2-yl)-2, 5-bis(2-ethylhexyl)pyrrolo[3, 4-c]pyrrole-1, 4-dione (PDPPP), 3, 6-bis(5-(4-fluorophenyl) thiophene-2-yl)-2, 5-bis(2-ethylhexyl)pyrrolo[3, 4-c]pyrrole-1, 4-dione (FPDPPPF) and 3, 6-bis(5-(4-n-butylphenyl)thiophene-2-yl)-2, 5-bis(2-ethylhexyl)pyrrolo[3, 4-c]pyrrole-1, 4-dione (BuPDPPPBu), have been studied in this work. Well aligned crystals of the three molecules were grown from para-xylene by droplet-pinned crystallizationmethod. FETs based on these aligned crystals exhibit a holemobility up to 0.19 cm2 V-1 s-1 and electronmobility up to 0.008 cm2 V-1 s-1. The achieved hole mobility is of the same order of magnitude as reported highest hole mobility for DPP-based small molecules, but it is much lower than that of the high-performanceDPP-based polymers. The relative lowmobility ismainly attributed to the rough crystal surfaces with steps and, thus, non-smooth charge transport channels at the interfaces between the crystals and the dielectrics. This work has implications for understanding the low charge mobility of DPP-based small molecules.
2016, 27(4): 527-534
Abstract:
Here we show a study of vibrational spectroscopic identification of a few typical organic compounds which are known as the main sources of organic aerosols (OAs) particle matter in air pollution. Raman and IR spectra of isoprene, terpenoids, pinenes and their mixture are meticulously examined, showing distinguishable intrinsic vibrational spectroscopic fingerprints for these chemicals, respectively. As a reference, first-principles calculations of Raman and infrared activities are also conducted. It is interestingly found that, the experimental spectra are peak-to-peak consistent with the DFT (Density Functional Theory)-calculated vibrational activities. Also found is that, in a certain case such as for β-pinene, a dimer model, rather than an isolated single molecular model, reproduces the experimental results, indicating unneglected intermolecular interactions. Starting with this study, we are endeavoring to advocate a database of Raman/IR fingerprint spectra for OA haze identification.
Here we show a study of vibrational spectroscopic identification of a few typical organic compounds which are known as the main sources of organic aerosols (OAs) particle matter in air pollution. Raman and IR spectra of isoprene, terpenoids, pinenes and their mixture are meticulously examined, showing distinguishable intrinsic vibrational spectroscopic fingerprints for these chemicals, respectively. As a reference, first-principles calculations of Raman and infrared activities are also conducted. It is interestingly found that, the experimental spectra are peak-to-peak consistent with the DFT (Density Functional Theory)-calculated vibrational activities. Also found is that, in a certain case such as for β-pinene, a dimer model, rather than an isolated single molecular model, reproduces the experimental results, indicating unneglected intermolecular interactions. Starting with this study, we are endeavoring to advocate a database of Raman/IR fingerprint spectra for OA haze identification.
2016, 27(4): 535-539
Abstract:
The salt effects on molecular orientation at air/liquid methanol interface were investigated by the polarization-dependent sum frequency generation vibrational spectroscopy (SFG-VS). We clarified that the average tilting angle of the methyl group to be θ=30°±5° at the air/pure methanol surface assuming a δ-function orientational distribution. Upon the addition of 3 mol/L NaI, the methyl group tilts further away from the surface normal with a new θ=41°±3°. This orientational change does not explain the enhancement of the SFG-VS intensities when adding NaI, implying the number density of the methanol molecules with a net polar ordering in the surface region also changed with the NaI concentrations. These spectroscopic findings shed new light on the salt effects on the surfaces structures of the polar organic solutions. It was also shown that the accurate determination of the bulk refractive indices and Raman depolarization ratios for different salt concentrations is crucial to quantitatively interpret the SFG-VS data.
The salt effects on molecular orientation at air/liquid methanol interface were investigated by the polarization-dependent sum frequency generation vibrational spectroscopy (SFG-VS). We clarified that the average tilting angle of the methyl group to be θ=30°±5° at the air/pure methanol surface assuming a δ-function orientational distribution. Upon the addition of 3 mol/L NaI, the methyl group tilts further away from the surface normal with a new θ=41°±3°. This orientational change does not explain the enhancement of the SFG-VS intensities when adding NaI, implying the number density of the methanol molecules with a net polar ordering in the surface region also changed with the NaI concentrations. These spectroscopic findings shed new light on the salt effects on the surfaces structures of the polar organic solutions. It was also shown that the accurate determination of the bulk refractive indices and Raman depolarization ratios for different salt concentrations is crucial to quantitatively interpret the SFG-VS data.
2016, 27(4): 540-544
Abstract:
In this study, a resorufin derivative RTP-1, which is a novel fluorescent "turn-on" probe for sensitive detection of hydrazine within 30 min, is designed and synthesized. The selective deprotection of the ester group of the probe by hydrazine led to a prominent enhancement of fluorescent intensity, aswell as a remarkable color change from colorless to pink, which could be distinguished by naked eye. The fluorescence enhancement showed decent linear relationship with hydrazine concentration ranging from 0 to 50 μmol/L, with a detection limit of 0.84 μmol/L. The specificity of RTP-1 for hydrazine to a number of metal ions, anions and amines is satisfactory. The sensing mechanism of RTP-1 and hydrazine was evaluated by HPLC, ESI mass spectrometry and density functional theory (DFT). Moreover, we have utilized this fluorescent probe for imaging hydrazine in living cells, and the fluorescence was clearly observed when the cells were incubated with hydrazine (100 μmol/L) for 30 min.
In this study, a resorufin derivative RTP-1, which is a novel fluorescent "turn-on" probe for sensitive detection of hydrazine within 30 min, is designed and synthesized. The selective deprotection of the ester group of the probe by hydrazine led to a prominent enhancement of fluorescent intensity, aswell as a remarkable color change from colorless to pink, which could be distinguished by naked eye. The fluorescence enhancement showed decent linear relationship with hydrazine concentration ranging from 0 to 50 μmol/L, with a detection limit of 0.84 μmol/L. The specificity of RTP-1 for hydrazine to a number of metal ions, anions and amines is satisfactory. The sensing mechanism of RTP-1 and hydrazine was evaluated by HPLC, ESI mass spectrometry and density functional theory (DFT). Moreover, we have utilized this fluorescent probe for imaging hydrazine in living cells, and the fluorescence was clearly observed when the cells were incubated with hydrazine (100 μmol/L) for 30 min.
2016, 27(4): 545-549
Abstract:
Oxidative stress stimulated by angiotensin II (Ang II) plays an important role in the progression of inflammation and cardiovascular disease. In this work, polythiophene modified with dihydropyridine groups (PTDHP) realized the control of oxidative stress induced by Angiotensin II stimulation in living cells, by inhibiting the activity of NADPH oxidase via DHP groups. Upon light irradiation, the PTDHP could sensitize surrounding oxygen molecules to generate reactive oxygen species (ROS). The generated ROS oxidized the pendant DHP of polythiophene into pyridine group, which inactivated the control ability of DHP to oxidative stress in living cells. Thus, PTDHP can not only control the intracellular oxidative stress effectively and suppress ROS to some degree in dark, but also regulate its anti-oxidative effect under light irradiation.
Oxidative stress stimulated by angiotensin II (Ang II) plays an important role in the progression of inflammation and cardiovascular disease. In this work, polythiophene modified with dihydropyridine groups (PTDHP) realized the control of oxidative stress induced by Angiotensin II stimulation in living cells, by inhibiting the activity of NADPH oxidase via DHP groups. Upon light irradiation, the PTDHP could sensitize surrounding oxygen molecules to generate reactive oxygen species (ROS). The generated ROS oxidized the pendant DHP of polythiophene into pyridine group, which inactivated the control ability of DHP to oxidative stress in living cells. Thus, PTDHP can not only control the intracellular oxidative stress effectively and suppress ROS to some degree in dark, but also regulate its anti-oxidative effect under light irradiation.
2016, 27(4): 550-554
Abstract:
Replacement of the methylene group at the C-8 position with an extended electronic conjugation is a new promising method to develop red-shifted coelenterazine derivatives. In this paper, we have described an oxygen-containing coelenterazine derivative with a significant red-shifted (63 nm) bioluminescence signal maximum relative to coelenterazine 400a (DeepBlueCTM, 1). In cell imaging, the sulfur-containing coelenterazine derivative displayed a significantly (1.77±0.09; P≤0.01) higher luminescence signal compared to coelenterazine 400a and the oxygen-containing coelenterazine derivative exhibited a slightly (0.74±0.08; P≤0.05) lower luminescence signal. It is beneficial to understand further the underlying mechanisms of bioluminescence.
Replacement of the methylene group at the C-8 position with an extended electronic conjugation is a new promising method to develop red-shifted coelenterazine derivatives. In this paper, we have described an oxygen-containing coelenterazine derivative with a significant red-shifted (63 nm) bioluminescence signal maximum relative to coelenterazine 400a (DeepBlueCTM, 1). In cell imaging, the sulfur-containing coelenterazine derivative displayed a significantly (1.77±0.09; P≤0.01) higher luminescence signal compared to coelenterazine 400a and the oxygen-containing coelenterazine derivative exhibited a slightly (0.74±0.08; P≤0.05) lower luminescence signal. It is beneficial to understand further the underlying mechanisms of bioluminescence.
2016, 27(4): 555-558
Abstract:
A series of novel daphneolone analogswas designed and synthesized on the basis of natural product 1, 5-diphenyl-2-penten-1-one (I) from Stellera chamaejasme L. as lead compound, whereby 2, 6-dimethylmorpholine moiety was introduced to replace 1-phenyl group. Their structures were confirmed by IR, 1H NMR, and HRMS (ESI) or elemental analysis, 13C NMR for some representative compounds. The two isomers of target compounds were separated and identified by NOESY technique and chemical method. All of the synthesized compounds have been evaluated for anti-plant pathogenic fungi activities. The results showed that some compounds exhibited moderate to good antifungal activities against tested fungi at the concentration of 50 mg/L. Among them, compound 7d, with a 4-bromine-substituted phenyl group and cis-2, 6-dimethylmorpholine moiety, displayed best activity with an EC50 of 23.87 μmol/L against Valsa mali, superior to lead compound I. In addition, preliminary structure-activity relationship analysis indicated that, between two isomers of target compounds, the antifungal activities of the isomer with cis-2, 6-dimethylmorpholine were better than the trans-isomer.
A series of novel daphneolone analogswas designed and synthesized on the basis of natural product 1, 5-diphenyl-2-penten-1-one (I) from Stellera chamaejasme L. as lead compound, whereby 2, 6-dimethylmorpholine moiety was introduced to replace 1-phenyl group. Their structures were confirmed by IR, 1H NMR, and HRMS (ESI) or elemental analysis, 13C NMR for some representative compounds. The two isomers of target compounds were separated and identified by NOESY technique and chemical method. All of the synthesized compounds have been evaluated for anti-plant pathogenic fungi activities. The results showed that some compounds exhibited moderate to good antifungal activities against tested fungi at the concentration of 50 mg/L. Among them, compound 7d, with a 4-bromine-substituted phenyl group and cis-2, 6-dimethylmorpholine moiety, displayed best activity with an EC50 of 23.87 μmol/L against Valsa mali, superior to lead compound I. In addition, preliminary structure-activity relationship analysis indicated that, between two isomers of target compounds, the antifungal activities of the isomer with cis-2, 6-dimethylmorpholine were better than the trans-isomer.
2016, 27(4): 559-562
Abstract:
Insect growth regulators play an important role in integrated pest management strategies. The FGLa-allatostatins (ASTs) are a family of neuropeptides that can inhibit juvenile hormone (JH) biosynthesis by the corpora allata (CA) of Diploptera punctata in vitro, are regarded as insect growth regulator candidates. In the search for new potential mimics and to explore the effect of linker length on inhibiting JH biosynthesis, a series of AST analogs were synthesized by modifying the linker of K24, which was found to have a significant effect on JH biosynthesis in vitro in our previous study. Functional evaluation demonstrated that all the target compounds can activate the Dippu-AstR, albeit with different potencies. Analog L6 with the longest linker (n=5), exhibited not only a promising effect on inhibition of JH biosynthesis both in vitro and in vivo, but also good activity in inhibiting basal oocyte growth. Structure-activity relationships (SAR) studies showed that longer linkers provided greater contribution to activity.
Insect growth regulators play an important role in integrated pest management strategies. The FGLa-allatostatins (ASTs) are a family of neuropeptides that can inhibit juvenile hormone (JH) biosynthesis by the corpora allata (CA) of Diploptera punctata in vitro, are regarded as insect growth regulator candidates. In the search for new potential mimics and to explore the effect of linker length on inhibiting JH biosynthesis, a series of AST analogs were synthesized by modifying the linker of K24, which was found to have a significant effect on JH biosynthesis in vitro in our previous study. Functional evaluation demonstrated that all the target compounds can activate the Dippu-AstR, albeit with different potencies. Analog L6 with the longest linker (n=5), exhibited not only a promising effect on inhibition of JH biosynthesis both in vitro and in vivo, but also good activity in inhibiting basal oocyte growth. Structure-activity relationships (SAR) studies showed that longer linkers provided greater contribution to activity.
2016, 27(4): 563-565
Abstract:
A family of tropos ligands bearing a N-heterocyclic carbene and a chiral oxazoline coordination group with a N-phenyl framework were easily prepared, and their coordination behavior with Pd(II) acetate was performed, affording a series of axially chiral palladium complexes in good yields.
A family of tropos ligands bearing a N-heterocyclic carbene and a chiral oxazoline coordination group with a N-phenyl framework were easily prepared, and their coordination behavior with Pd(II) acetate was performed, affording a series of axially chiral palladium complexes in good yields.
2016, 27(4): 566-570
Abstract:
In order to discover highly active ecdysone analogs, a series of new substituted pyrazole amide derivatives were obtained using structure-guided optimization method and further screened for their insecticidal activities, in the basis of the core structures of the two active compounds N-(3-methoxyphenyl)-3-(tert-butyl)-1-phenyl-1H-pyrazole-5-carboxamide (6e) and N-(4-(tert-butyl)phenyl)-3-(tert-butyl)-1-phenyl-1H-pyrazole-5-carboxamide (6i), previously presented by us. The chemical structures of the title compounds were identified by spectral analyses. The preliminary bioassay results indicated that one among the synthesized pyrazole derivatives, compound 34, endowed with good activity against Mythimna Separata at 10 mg/L, which was equal to that displayed by the positive control tebufenozide. In addition, examples of molecular docking and molecular dynamics studies demonstrated that 34 may be the potential inhibitor to EcR and its docking conformation was similar to that of tebufenozide. In addition, increasing the hydrophobic effect and considering the suitable bulk effect on pyrazole ring are beneficial to the inhibiting activity to EcR and activity in vivo.
In order to discover highly active ecdysone analogs, a series of new substituted pyrazole amide derivatives were obtained using structure-guided optimization method and further screened for their insecticidal activities, in the basis of the core structures of the two active compounds N-(3-methoxyphenyl)-3-(tert-butyl)-1-phenyl-1H-pyrazole-5-carboxamide (6e) and N-(4-(tert-butyl)phenyl)-3-(tert-butyl)-1-phenyl-1H-pyrazole-5-carboxamide (6i), previously presented by us. The chemical structures of the title compounds were identified by spectral analyses. The preliminary bioassay results indicated that one among the synthesized pyrazole derivatives, compound 34, endowed with good activity against Mythimna Separata at 10 mg/L, which was equal to that displayed by the positive control tebufenozide. In addition, examples of molecular docking and molecular dynamics studies demonstrated that 34 may be the potential inhibitor to EcR and its docking conformation was similar to that of tebufenozide. In addition, increasing the hydrophobic effect and considering the suitable bulk effect on pyrazole ring are beneficial to the inhibiting activity to EcR and activity in vivo.
2016, 27(4): 571-574
Abstract:
An efficient copper-catalyzed decarboxylative hydroboration of phenylpropiolic acids with bis(pinacolato) diboron was developed, affording β-vinylboronates as the only products in high yields. Extra hydrogen sources such as methanol are not needed in this catalytic system. This reaction could be performed successfully under ligand- and base-free conditions. It demonstrated that phenylpropiolic acids can be employed as alkyne synthons in the hydroboration reaction and exhibited good reactivity and higher selectivity than terminal alkynes.
An efficient copper-catalyzed decarboxylative hydroboration of phenylpropiolic acids with bis(pinacolato) diboron was developed, affording β-vinylboronates as the only products in high yields. Extra hydrogen sources such as methanol are not needed in this catalytic system. This reaction could be performed successfully under ligand- and base-free conditions. It demonstrated that phenylpropiolic acids can be employed as alkyne synthons in the hydroboration reaction and exhibited good reactivity and higher selectivity than terminal alkynes.
2016, 27(4): 575-578
Abstract:
The functionalized spiro[indoline-3, 4'-pyrano[3, 2-h]quinolines] were efficiently prepared in high yields from three-component reaction of 8-hydroxyquinoline, isatins and malononitrile or ethyl cyanoacetate in ethanol at room temperature for about 12 h in the presence of piperidine.
The functionalized spiro[indoline-3, 4'-pyrano[3, 2-h]quinolines] were efficiently prepared in high yields from three-component reaction of 8-hydroxyquinoline, isatins and malononitrile or ethyl cyanoacetate in ethanol at room temperature for about 12 h in the presence of piperidine.
2016, 27(4): 579-582
Abstract:
Bioactive calcium silicates prepared by sol-gel routes mainly use calcium nitrate as the calcium precursor. However, the toxic nitrate ions are usually removed by calcination (i.e. 550℃ or over), which poses great challenge for the in situ preparation of inorganic/polymer composites, as polymer moieties could not survive such temperatures. In this study, we prepared 70Si30Ca (70 mol% SiO2 and 30 mol% CaO) bioactive glass at low temperatures where polymer could survive (i.e. 200℃ and 350℃), and proposed to remove the residual nitrate ions through soaking. Deionized water and simulated body fluid (SBF) were employed as the soaking medium. The results showed that the residual nitrate ions could be removed as quickly as 0.5 h while maintain the bioactivity of the samples. This technique may open the possibility of preparing sol-gel derived bioactive glass/polymer hybrids in situ with reduced potential toxicity.
Bioactive calcium silicates prepared by sol-gel routes mainly use calcium nitrate as the calcium precursor. However, the toxic nitrate ions are usually removed by calcination (i.e. 550℃ or over), which poses great challenge for the in situ preparation of inorganic/polymer composites, as polymer moieties could not survive such temperatures. In this study, we prepared 70Si30Ca (70 mol% SiO2 and 30 mol% CaO) bioactive glass at low temperatures where polymer could survive (i.e. 200℃ and 350℃), and proposed to remove the residual nitrate ions through soaking. Deionized water and simulated body fluid (SBF) were employed as the soaking medium. The results showed that the residual nitrate ions could be removed as quickly as 0.5 h while maintain the bioactivity of the samples. This technique may open the possibility of preparing sol-gel derived bioactive glass/polymer hybrids in situ with reduced potential toxicity.
2016, 27(4): 583-587
Abstract:
In this work, a monomer with double bond was introduced to the surface of clay nanosheets via inclusion complexation between cyclodextrin (CD) host and azobenzene (Azo) guest, as well as electrostatic interaction between clay nanoplatelets and cations of azobenzene derivatives. The obtained supra-structure acts as a supramolecular cross-linker in its copolymerization with macromonomer PEG resulting in a hybrid supramolecular hydrogel. Only viscous liquid was obtained in the absence of clay nanoplatelets, revealing the supramolecular cross-linker played an important role in the hydrogel formation. Such hybrid supramolecular hydrogel exhibited good stability and shear thinning property.
In this work, a monomer with double bond was introduced to the surface of clay nanosheets via inclusion complexation between cyclodextrin (CD) host and azobenzene (Azo) guest, as well as electrostatic interaction between clay nanoplatelets and cations of azobenzene derivatives. The obtained supra-structure acts as a supramolecular cross-linker in its copolymerization with macromonomer PEG resulting in a hybrid supramolecular hydrogel. Only viscous liquid was obtained in the absence of clay nanoplatelets, revealing the supramolecular cross-linker played an important role in the hydrogel formation. Such hybrid supramolecular hydrogel exhibited good stability and shear thinning property.
2016, 27(4): 588-592
Abstract:
The detection of long-chain branches (LCB) in polyethylene is of considerable importance as the processing properties of polyethylene are strongly affected by even a small amount of LCB. While the conventional characterization techniques such as GPC-MALS and 13C NMR fail or take very long time to detect low content of LCB, we turn to the rheological method, which is more sensitive to LCB. In our study, we performed oscillatory shear test, creep test and stress relaxation test on two series of metallocene linear low density polyethylene (LLDPE), revealing that the resins with LCB show higher zero-shear-rate viscosity, retarded relaxation and higher flow activation energy than those without or with less LCB. The resins with LCB showed shear thinning at very low shear rate and their zero-shear-rate viscosities were obtained via creep test. The content of LCB was quantitatively estimated from the flow activation energy. In addition, the modulus-time curves during stress relaxation of melt of the different resins obeyed the power law. The exponent of the resins with more LCB was -0.7, different from that of the resins with less LCB, around -1.7.
The detection of long-chain branches (LCB) in polyethylene is of considerable importance as the processing properties of polyethylene are strongly affected by even a small amount of LCB. While the conventional characterization techniques such as GPC-MALS and 13C NMR fail or take very long time to detect low content of LCB, we turn to the rheological method, which is more sensitive to LCB. In our study, we performed oscillatory shear test, creep test and stress relaxation test on two series of metallocene linear low density polyethylene (LLDPE), revealing that the resins with LCB show higher zero-shear-rate viscosity, retarded relaxation and higher flow activation energy than those without or with less LCB. The resins with LCB showed shear thinning at very low shear rate and their zero-shear-rate viscosities were obtained via creep test. The content of LCB was quantitatively estimated from the flow activation energy. In addition, the modulus-time curves during stress relaxation of melt of the different resins obeyed the power law. The exponent of the resins with more LCB was -0.7, different from that of the resins with less LCB, around -1.7.
2016, 27(4): 593-596
Abstract:
Combining with electrospray ionization (ESI) mass spectrometry, infrared photodissociation (IRPD) spectroscopy is a powerful method to study structures of cluster ions in the gas phase. In this paper, infrared photodissociation spectrum of Pro4H+ in the range of 2700-3600 cm-1 was obtained experimentally. Both theoretically predicted spectra of the two most stable isomers of Pro4-1 and Pro4-2 obtained at the level of M062X/6-31+G(d, p) are in good consistent with the experimental results. The two isomers have similar structures and close energies. Both of them only consist of zwitterionic units, indicating the strong salt-bridged interactions inside the clusters. And the calculated collision cross section (ccs) of Pro4-1 is found to be very close to the experimental result previously reported.
Combining with electrospray ionization (ESI) mass spectrometry, infrared photodissociation (IRPD) spectroscopy is a powerful method to study structures of cluster ions in the gas phase. In this paper, infrared photodissociation spectrum of Pro4H+ in the range of 2700-3600 cm-1 was obtained experimentally. Both theoretically predicted spectra of the two most stable isomers of Pro4-1 and Pro4-2 obtained at the level of M062X/6-31+G(d, p) are in good consistent with the experimental results. The two isomers have similar structures and close energies. Both of them only consist of zwitterionic units, indicating the strong salt-bridged interactions inside the clusters. And the calculated collision cross section (ccs) of Pro4-1 is found to be very close to the experimental result previously reported.
2016, 27(4): 597-601
Abstract:
In the present work, we report nitrogen and phosphorus co-doped 3-D structured carbon nanotube intercalated graphene nanoribbon composite. The graphene nanoribbons are prepared via partial exfoliation of multi-walled carbon nanotubes. In the graphene nanoribbons/CNTs composite, carbon nanotubes play a role of skeleton and support the exfoliated graphene nanoribbons to form the stereo structure. After high temperature heat-treatment with ammonium dihydrogen phosphate, the unique structure reserves both the properties of carbon nanotube and graphene, exhibiting excellent catalytic performance for the ORR with excellent onset and half-wave potential, which is similar to commercial Pt/C electrocatalysts.
In the present work, we report nitrogen and phosphorus co-doped 3-D structured carbon nanotube intercalated graphene nanoribbon composite. The graphene nanoribbons are prepared via partial exfoliation of multi-walled carbon nanotubes. In the graphene nanoribbons/CNTs composite, carbon nanotubes play a role of skeleton and support the exfoliated graphene nanoribbons to form the stereo structure. After high temperature heat-treatment with ammonium dihydrogen phosphate, the unique structure reserves both the properties of carbon nanotube and graphene, exhibiting excellent catalytic performance for the ORR with excellent onset and half-wave potential, which is similar to commercial Pt/C electrocatalysts.
2016, 27(4): 602-606
Abstract:
The formation of coordinated dimeric complexes bridged by axial ligands on surface is observed with the help of a 1, 3, 5-tris(10-carboxydecyloxy)benzene (TCDB) template through scanning tunneling microscopy (STM). STM images of molecular adlayers of zinc tetraphenylporphyrin (ZnTPP), zinc phthalocyanine (ZnPc), and their mixture are reported. ZnTPP and ZnPc can spontaneously form highly an ordered structure with a 1:1 molar ratio, which is different from that of individual ZnPc. The coordinated bimolecular complexes bridged with axial ligands, simply as ZnPc-DPP-ZnTPP and ZnPc-DPE-ZnPc, are presented and the corresponding surface structures are compared. ZnPc and ZnTPP can be connected by an axial ligand DPP and formed assembled structures out of surface. Two types of arrays with entirely new structure are obtained for the ZnPc-DPE-ZnPc complex. These bridged hybrid complexes provide an example of design of self-organized crystals on the basis of coordination through non-covalent interactions.
The formation of coordinated dimeric complexes bridged by axial ligands on surface is observed with the help of a 1, 3, 5-tris(10-carboxydecyloxy)benzene (TCDB) template through scanning tunneling microscopy (STM). STM images of molecular adlayers of zinc tetraphenylporphyrin (ZnTPP), zinc phthalocyanine (ZnPc), and their mixture are reported. ZnTPP and ZnPc can spontaneously form highly an ordered structure with a 1:1 molar ratio, which is different from that of individual ZnPc. The coordinated bimolecular complexes bridged with axial ligands, simply as ZnPc-DPP-ZnTPP and ZnPc-DPE-ZnPc, are presented and the corresponding surface structures are compared. ZnPc and ZnTPP can be connected by an axial ligand DPP and formed assembled structures out of surface. Two types of arrays with entirely new structure are obtained for the ZnPc-DPE-ZnPc complex. These bridged hybrid complexes provide an example of design of self-organized crystals on the basis of coordination through non-covalent interactions.
2016, 27(4): 607-612
Abstract:
We designed and constructed a new family of 60° dendritic dipyridyl donors, from which two novel triangular metallodendrimers were successfully prepared via coordination-driven self-assembly. Inspired by the existence of multiple intermolecular interactions (e.g., π-π stacking and CH-π interactions) imposed by the DMIP-functionalized poly(benzyl ether) dendrons, their hierarchical selfassembly behaviors were studied in various mixed solvents by using scanning electron microscopy (SEM). Interestingly, it was found that the morphologies of the obtainedmetallodendrimers were highly depended on the dendron generation. For example, the first-generation metallodendrimer was able to hierarchically self-assemble into the spherical nanostructures in various mixed solvents. However, the nanofibers were observed for the second-generation metallodendrimer under the similar conditions. Furthermore, the driven force for the formation of such ordered nanostructures was investigated by using 1H NMR and fluorescence spectroscopy.
We designed and constructed a new family of 60° dendritic dipyridyl donors, from which two novel triangular metallodendrimers were successfully prepared via coordination-driven self-assembly. Inspired by the existence of multiple intermolecular interactions (e.g., π-π stacking and CH-π interactions) imposed by the DMIP-functionalized poly(benzyl ether) dendrons, their hierarchical selfassembly behaviors were studied in various mixed solvents by using scanning electron microscopy (SEM). Interestingly, it was found that the morphologies of the obtainedmetallodendrimers were highly depended on the dendron generation. For example, the first-generation metallodendrimer was able to hierarchically self-assemble into the spherical nanostructures in various mixed solvents. However, the nanofibers were observed for the second-generation metallodendrimer under the similar conditions. Furthermore, the driven force for the formation of such ordered nanostructures was investigated by using 1H NMR and fluorescence spectroscopy.
2016, 27(4): 613-618
Abstract:
In this work, a series of molybdovanadophosphoric heteropoly acid quaternary ammonium salts (H3+xPMo12-xVxO40-T) were synthesized and employed as a reaction inhibitor in the selfpolymerization of methyl methacrylate (MMA). The polymerization inhibition effect of H3+xP-Mo12-xVxO40-T with different number of vanadium atoms and reaction dosages was investigated using differential scanning calorimetry (DSC). It shows that the inhibitory effect was improved with the increasing dosages of H3+xPMo12-xVxO40-T, and the polymerization inhibition was also affected by the number of vanadium atoms in the H3+xPMo12-xVxO40-T. Furthermore, cyclic voltammograms (CV) was used to probe the mechanism of the inhibition reaction with H3+xPMo12xVxO40-T. The result of CV indicates that the inhibition reaction is an oxidation-reduction reaction. H3+xPMo12-xVxO40-T can react directly with the MMA monomer radicals, which eliminated the MMA monomers, and therefore the self-polymerization of the MMA can be effectively inhibited by H3+xPMo12-xVxO40-T.
In this work, a series of molybdovanadophosphoric heteropoly acid quaternary ammonium salts (H3+xPMo12-xVxO40-T) were synthesized and employed as a reaction inhibitor in the selfpolymerization of methyl methacrylate (MMA). The polymerization inhibition effect of H3+xP-Mo12-xVxO40-T with different number of vanadium atoms and reaction dosages was investigated using differential scanning calorimetry (DSC). It shows that the inhibitory effect was improved with the increasing dosages of H3+xPMo12-xVxO40-T, and the polymerization inhibition was also affected by the number of vanadium atoms in the H3+xPMo12-xVxO40-T. Furthermore, cyclic voltammograms (CV) was used to probe the mechanism of the inhibition reaction with H3+xPMo12xVxO40-T. The result of CV indicates that the inhibition reaction is an oxidation-reduction reaction. H3+xPMo12-xVxO40-T can react directly with the MMA monomer radicals, which eliminated the MMA monomers, and therefore the self-polymerization of the MMA can be effectively inhibited by H3+xPMo12-xVxO40-T.