An operationally simple approach for the tandem synthesis of isoquinolines by the reaction of o-alkynylalde- hydes with ammonium bicarbonate via Ag-catalyzed 6-endo-dig ring closure is described. The reaction conditio...An operationally simple approach for the tandem synthesis of isoquinolines by the reaction of o-alkynylalde- hydes with ammonium bicarbonate via Ag-catalyzed 6-endo-dig ring closure is described. The reaction conditions and the scope of the reaction are examined, and a variety of substituted isoquinolines are prepared in moderate to excellent yields.展开更多
Organic-inorganic MoO_(3)/PI(MoPI)composites were prepared using a simple one-pot thermal copolymerization method.The resulting composites exhibited enhanced photocatalytic activity for the selective oxidation of benz...Organic-inorganic MoO_(3)/PI(MoPI)composites were prepared using a simple one-pot thermal copolymerization method.The resulting composites exhibited enhanced photocatalytic activity for the selective oxidation of benzylamine to N-benzylidene benzylamine(N-BDBA)in ambient air under simulated solar light irradiation compared to pristine MoO_(3) or polyimide(PI).In particular,the MoPI composite with a 0.3:1 molar ratio of Mo to melamine,referred to as MoPI-0.3,demonstrated the best performance in the photo-oxidation of benzylamine,achieving a benzylamine conversion of 95%with a N-BDBA selectivity exceeding 99%after 3 h irradiation.The enhanced photocatalytic activity of the MoPI-0.3 catalyst was attributed to the formation of a direct Z-scheme heterojunction between MoO_(3) and PI,facilitating more efficient separation of the photoinduced electrons and holes.Additionally,the MoPI-0.3 composite maintained considerably high activity over four consecutive cycles,highlighting its good stability and recyclability.Furthermore,the MoPI-0.3 composite could photo-oxidize benzylamine derivatives and heterocyclic amines to their corresponding imines,demonstrating the universal applicability of this composite catalyst.展开更多
Polyimide(PI) is an organic polymer material with good stability and diverse sources that has attracted widespread attention in the field of photocatalysis. In this study, a series of PI photocatalysts were synthesize...Polyimide(PI) is an organic polymer material with good stability and diverse sources that has attracted widespread attention in the field of photocatalysis. In this study, a series of PI photocatalysts were synthesized by a thermal polymerization approach using pyromellitic dianhydride(PMDA) and various diamine monomers(melamine(MA), 4,4′-oxydianiline, and melem) as the precursors as well as different heating rates. The effects of the diamine precursor and heating rate on the structure, composition, morphology, and optical properties of the as-prepared PI materials were systematically investigated by various characterization techniques. The selective photo-oxidation of benzylamine was used as a model reaction to evaluate the photocatalytic activities of the resulting PI samples for the oxidation of amines to imines. The results revealed that the PI sample prepared using MA and PMDA as the precursors and a heating rate of 7 ℃/min(MA-PI-7) exhibited the best catalytic performance, with 98% benzylamine conversion and 98% selectivity for N-benzylidene benzylamine after 4 h of irradiation. Several benzylamine derivatives and heterocyclic amines also underwent the photo-oxidation reaction over the MA-PI-7 catalyst to afford the corresponding imines with good activity. In addition, MA-PI-7 exhibited good stability over four successive photocatalytic cycles.展开更多
Eleven new imine derivatives 6 containing 1H-1,2,4-triazole and thiazole rings were synthesized by the condensation of 5-((1H- 1,2,4-triazol-1-yl)methyl)-4-tert-butylthiazol-2-amine with various substituted benzaldehy...Eleven new imine derivatives 6 containing 1H-1,2,4-triazole and thiazole rings were synthesized by the condensation of 5-((1H- 1,2,4-triazol-1-yl)methyl)-4-tert-butylthiazol-2-amine with various substituted benzaldehydes.The structures of the title compounds were characterized by ~1H NMR,MS and elemental analysis.The plant-growth regulatory activities of these compounds were evaluated.The primary bioassay results indicated that these target compounds exhibited promising plant-growth regulatory activities.展开更多
A series of polymeric ionic liquids(PILs)used as effective heterogeneous catalysts for biodiesel production via esterification of free fatty acids(FFAs)were effectively prepared by the reaction of poly(ethylene imine)...A series of polymeric ionic liquids(PILs)used as effective heterogeneous catalysts for biodiesel production via esterification of free fatty acids(FFAs)were effectively prepared by the reaction of poly(ethylene imine)(PEI)polymers with different molecular weight and 1,3-propanesultone,followed by the further acidification with differential effective acids,i.e.H2SO4,CF3SO3H,CH3SO3H or p-toluenesulfonic acid(p-TSA).Ultrahigh acidity and catalytic performance were achieved and could be fine-tuned by simply adjusting the molecular weight of PEI and by further treatment of acids.Specifically,under the optimal conditions(i.e.reaction temperature was 70℃,reaction time was 2.0 h,catalyst dosage was 3.15%(mass),and alcohol/acid molar ratio was 14:1)acquired through the Box-BEHNKEN response surface methodology,a high oleic acid conversion of 98.42%could be obtained over the optimal PIL,PEI(70000)-PS-p-TSA.Additionally,our PILs also showed high generality for esterification of other FFAs,with general high conversion over 90%noted in each case even under much milder reaction conditions compared to other conventional catalysts.展开更多
Background:Ethoxyquin(EQ)is a common antioxidant which is widely used in animal feed.But the supplement of EQ in animal feed may lead to the residues of EQ and its major oxidation products:ethoxyquin quinone imine(EQI...Background:Ethoxyquin(EQ)is a common antioxidant which is widely used in animal feed.But the supplement of EQ in animal feed may lead to the residues of EQ and its major oxidation products:ethoxyquin quinone imine(EQI)and ethoxyquin dimer(EQDM)in animal tissue.Thus,it would pose potential health hazards to consumers.However,the method for the simultaneous determination of EQ,EQI and EQDM in animal tissues is currently not available,and the accumulation extend of these chemicals in animal tissues after EQ administration remains to be evaluated.Results:A gas chromatography-tandem mass spectrometry method was successfully developed for the simultaneous determination of EQ,EQI and EQDM in swine tissues.The quantitative limits of EQ,EQI and EQDM can achieve to 0.5,5.0 and 5.0μg/kg in swine tissues,respectively.The spiked-recovery ratios of the three analytes(5–2000μg/kg)were in the range of 64.7%–100.7%with relative standard deviations below 11.6%.Moreover,the utilization of this method for the analysis of actual swine tissue samples revealed that the application of commercial EQ additive in swine diet would produce the residues of all the three chemicals(EQ,EQI and EQDM)in fat,kidney,liver and muscle.Conclusions:The assay accuracy and precision of this GC-MS/MS method can meet the requirement of quantitative analysis.Meanwhile,the safety of EQ as a feed additive should be seriously considered with regard to food safety concerns since the oxidation product of EQ may have potential carcinogenicity.展开更多
The addition of allyltrimethylsilane to tert-butanesulfinyl imines triggered by tetra-n-butylammonium fluoride (TBAF) in the presence of 4A molecular sieves has been studied, and homoallylsulfinamides were obtained ...The addition of allyltrimethylsilane to tert-butanesulfinyl imines triggered by tetra-n-butylammonium fluoride (TBAF) in the presence of 4A molecular sieves has been studied, and homoallylsulfinamides were obtained in good yields with moderate to high diastereoselectivities.展开更多
Two novel C-nor-B-homo aconane-type diterpenes 4 and 5, featuring a unique eight-membered ring system, were obtained by the treatment of C-nor-C19-diterpenoid alkaloid 3 with HNO2 in 8% and 21% yields, respectively. S...Two novel C-nor-B-homo aconane-type diterpenes 4 and 5, featuring a unique eight-membered ring system, were obtained by the treatment of C-nor-C19-diterpenoid alkaloid 3 with HNO2 in 8% and 21% yields, respectively. Structures of these two compounds were established based on the combination of spectroscopic data, including HRESIMS, 1D and 2D NMR data. A olausible mechanism for the formation of 4 and 5 is also presented.展开更多
The synthesis and properties of three kinds of hyper-dispersants are studied in this paper, which are non-terminated, carboxyl-terminated and polyethylene imine grafted poly(hydroxyl carboxylic acid) ester. The hype...The synthesis and properties of three kinds of hyper-dispersants are studied in this paper, which are non-terminated, carboxyl-terminated and polyethylene imine grafted poly(hydroxyl carboxylic acid) ester. The hyper-dispersants are synthesized by the materials of 12-hydroxy-stearic acid, stearic acid and polyethylene imine, which are used to improve the dispersion properties of nano titanium dioxide (nano-TiO2) in low-concentration resin solution system. The influences of hyper-dispersants on the viscosity and stability of the system are studied. It is found that polyethylene imine grafted hyper-dispersant has the best dispersion performance in nano-TiO2 dispersion system, and the optimal content of the hyper-dispersant is 4%.展开更多
Nine new a-aminophosphonate derivatives containing cyclopropane moiety have been synthesized via conventional and microwave irradiation methods under solvent- and catalyst-free condition. The structures of the title c...Nine new a-aminophosphonate derivatives containing cyclopropane moiety have been synthesized via conventional and microwave irradiation methods under solvent- and catalyst-free condition. The structures of the title compounds have been confirmed by ^1H NMR, ^31p NMR FTIR, EI-MS and FTICR-MS. Their antifungal activities were evaluated in vivo and some of the compounds were found to exhibit excellent antifungal activities against Corynespora cassiicola, Pseudomonas syringae pv. Lachrymans, Pseudoperonospora cubensis and Sclerotinia sclerotiorum.展开更多
Synthesized and characterized new chiral palladium complexes, some of which contain asymmetric donor nitrogen atom. Nitrogen-containing derivatives (+) - and (-)-2α-hydroxypinan-3-one- (1R,2R,5R)-3-(benzylimino)-2,6,...Synthesized and characterized new chiral palladium complexes, some of which contain asymmetric donor nitrogen atom. Nitrogen-containing derivatives (+) - and (-)-2α-hydroxypinan-3-one- (1R,2R,5R)-3-(benzylimino)-2,6,6-trimethylbicy- clo[3.1.1]heptane-2-ol (HL1), (1S,2S,3S,5S)-3- (benzylamino)-2,6, 6-trimethylbicyclo[3.1.1]- heptane-2-ol (HL2), (1R,2R,5R)-3-((S)-α-methyl- benzylimino)-2,6,6-trimethylbicyclo[3.1.1]- heptane-2-ol (HL3), (1R,2R,3R,5R)-3-((S)-α-methyl- benzylamino)-2,6,6-trimethylbicyclo[3.1.1]- heptane-2-ol (HL4) -were studied as optically active ligands.展开更多
Treatment of 3-acetylpseudaconie 6 and 3. 13-diacetylyunnaconitine 9 withNBS/acetone-H2O(2:1) at room temperature produced corresponding imine derivatives & and 10.respectively. in good yields. This is a novel si...Treatment of 3-acetylpseudaconie 6 and 3. 13-diacetylyunnaconitine 9 withNBS/acetone-H2O(2:1) at room temperature produced corresponding imine derivatives & and 10.respectively. in good yields. This is a novel simple and convenient method for preparation of theimine compounds.展开更多
A novel template-free oxalate route was applied to synthesize different mesoporous manganese oxides(amorphous manganese oxide(AMO),Mn5 O8,Mn3 O4,Mn O2)in the narrow temperature range from 350°C to 400°C by c...A novel template-free oxalate route was applied to synthesize different mesoporous manganese oxides(amorphous manganese oxide(AMO),Mn5 O8,Mn3 O4,Mn O2)in the narrow temperature range from 350°C to 400°C by controlling the calcination conditions,which were employed as the efficient catalysts for the oxidative coupling of alcohols with amines to imines.The chemical and structural properties of the manganese oxides were characterized by the methods of thermogravimetry analysis and heat flow(TG-DSC),X-ray diffraction(XRD),nitrogen sorption,scanning electron microscope(SEM),transmission electron microscopy(TEM),X-ray photoelectron spectroscopy(XPS),H2 temperature-programmed reduction(H2-TPR),and inductively coupled plasma optical emission spectrometry(ICP-OES)techniques.The structures of different manganese oxides were confirmed by characterization.The M-350(AMO)presented the maximum surface area,amorphous nature,the lowest reduction temperature,the higher(Mn3++Mn4+)/Mn2+ratio,and the higher adsorbed oxygen species compared to other samples.Among the catalysts,M-350 showed the best catalytic performance using air as an oxidant,and the conversion of benzyl alcohol(BA)and the selectivity of N-benzylideneaniline(NBA)reached as high as 100%and 97.1%respectively at the lower reaction temperature(80°C)for 1 h.M-350 had also the highest TOF value(0.0100 mmol·mg-1·h-1)compared to the other manganese oxide catalysts.The catalyst was reusable and gave 95.8%conversion after 5 reuse tests,the XRD pattern of the reactivated M-350 did not show any obvious change.Lattice oxygen mobility and(Mn3++Mn4+)/Mn2+ratio were found to play the important roles in the catalytic activity of aerobic reactions.展开更多
Many proline-catalyzed asymmetric addition reactions with ketones as substrates were assumed to involve a key intermediate, an enamine, produced by the condensation of proline and ketone. In this paper, the key interm...Many proline-catalyzed asymmetric addition reactions with ketones as substrates were assumed to involve a key intermediate, an enamine, produced by the condensation of proline and ketone. In this paper, the key intermediate enamines derived from L-proline and cyclohexanone (or acetone) as well as the corresponding oxazolidinone and imine tautomers have been investigated by means of density functional calculations at the B3LYP/6-311+G^** level. The predicted order of stability for these tautomers is oxazolidinones 〉 enamines 〉 imines in gas phase and oxazolidinones 〉 imines 〉 enamines in aprotic THF solvent. This prediction explains why enamine intermediate can not be observed experimentally. The predicted energy/enthalpy difference between the formal oxazolidinone structure and the zwitterionic imine structures is very small in THF solvent, suggesting the oxazolidinone-to-imine tautomerization can be readily induced in solvent. ^13C NMR chemical shifts of the oxazolidinone and imine structures have been computed and used to explain the experimental NMR spectra observed in oxazolidinone-to-imine tautomerization induced by protic solvent.展开更多
1-Phenyl-1,3-butandione benzidine diketoimine 2a (C32H28N2O2, Mr = 472.56) was synthesized in high yield by the reaction of 1-phenyl-1,3-butandione with benzidine in absolute ethanol, and determined by X-ray structu...1-Phenyl-1,3-butandione benzidine diketoimine 2a (C32H28N2O2, Mr = 472.56) was synthesized in high yield by the reaction of 1-phenyl-1,3-butandione with benzidine in absolute ethanol, and determined by X-ray structure analysis. It crystallizes in the orthorhombic system, space group P21/c with a = 7.9839(16), b = 12.910(3), c = 12.358(3)A, α = 90.00, β= 93.71(3),γ = 90.00°, V = 1271.1(4) A3, Z = 2, Dc = 1.235 g/cm^3,/1 = 0.077 mm^-1, F(000) = 500, the final R = 0.0717 and wR = 0.1187. It presents a linear centrosymmetric framework constituted by a linkage of benzidine as a bridge and two terminal 1-phenyl-1,3-butanedione moieties.展开更多
Boronic acid compounds with different substituted groups were handled to synthesize various ligands encoded as B1, B2, B3, B4, BS, B6, B7 and BS. B5 and B7 were tested for the cytotoxic activity against the prostate c...Boronic acid compounds with different substituted groups were handled to synthesize various ligands encoded as B1, B2, B3, B4, BS, B6, B7 and BS. B5 and B7 were tested for the cytotoxic activity against the prostate cancer cells and it was found that the cell viability of cancer cells was decreased while most of the healthy cells could still be viable. 5 μM solutions of B5 and B7 decreased the cell viability to 33% and 44%; whereas healthy cells were 71% and 95%, respectively, after treatment. Antimicrobial properties were explored against the bacterial and fungal microorganisms with B1, B5 and BZ The inhibition zones were evaluated for all boronic structures, and the growth inhibition zones were determined in a range of 7-13 mm diameter for different microorganism species. Staphylococcus aureus was the common micro- organism that three boronic compounds with imine ligands showed the activity. Antioxidant features of B2, B3, B4, B5, B6, B7 and B8 were investigated by different processes such as Beta-carotene bleaching (BCB), 2,2-diphenyl picryl hydrazyl (DPPH), 2,2″-azino-bis( 3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and CUPric reducing antioxidant capacity (CLIPRAC) methods. Significant antioxidant activity was achieved by the phenyl boronic based ligands and these compounds demonstrated as much activity as standards (α-Toc and BHT). In addition, all structures were applied properly without any decomposition during the experiments. They were rather stable both in aqueous media and solid state.展开更多
In past decades, alginate-based multilayer microcapsules have been given important attention in various pharmaceutical investigations. Alginate-poly l lysine-alginate(APA) is studied the most. Due to the similarity be...In past decades, alginate-based multilayer microcapsules have been given important attention in various pharmaceutical investigations. Alginate-poly l lysine-alginate(APA) is studied the most. Due to the similarity between the structure of polyethyleneimine(PEI) and poly-L-lysine(PLL) and also lower price of PEI than PLL, this study was conducted to compare the efficacy of linear(LPEI) and branch(BPEI) forms of PEI with PLL as covering layers in fabrication of microcapsules. The microcapsules were fabricated using electrostatic bead generator and their shape/size, surface roughness, mechanical strength, and interlayer interactions were also investigated using optical microscopy, AFM, explosion test and FTIR, respectively. Furthermore, cytotoxicity was evaluated by comparing the two anionic final covering layers alginate(Alg) and sodium cellulose sulphate(NCS) using MTT test. BPEI was excluded from the rest of the study due to its less capacity to strengthen the microcapsules and also the aggregation of the resultant alginate-BPEI-alginate microcapsules, while LPEI showed properties similar to PLL. MTT test also showed that NCS has no superiority over Alg as final covering layer. Therefore, it is concluded that, LPEI could be considered as a more cost effective alternative to PLL and a promising subject for future studies.展开更多
A series of aromatic imines were reduced to corresponding amines in excellent yields by 2-phenyl-N. N-dimethylbenzimidazoline (PDMBI) photochemically in the presence of magnesium perchloride (Mg(ClO4)(2)). A Mg2+ medi...A series of aromatic imines were reduced to corresponding amines in excellent yields by 2-phenyl-N. N-dimethylbenzimidazoline (PDMBI) photochemically in the presence of magnesium perchloride (Mg(ClO4)(2)). A Mg2+ mediated photoinduced electron transfer mechanism was proposed.展开更多
An unexpected tricyclic compound 2,3,3a,4,5,9b-hexahydrophenylfuro[3.2-c] quinoline 4 and its aromatized product 6 were obtained when the cycloaddtion of imine 1 and substituted norbornene 2 was carried out in THF wit...An unexpected tricyclic compound 2,3,3a,4,5,9b-hexahydrophenylfuro[3.2-c] quinoline 4 and its aromatized product 6 were obtained when the cycloaddtion of imine 1 and substituted norbornene 2 was carried out in THF with a catalytic amount of boron trifluoride. The structures of the products were determined by spectral data and the mechanism of reaction was substantiated by the imitation reaction.展开更多
基金The generous financial support from the National Natural Science Foundation of China (Nos. 21372070 and 21471052) and the Hunan Provincial Education Department Scientific Research Fund (No. 14k035) are gratefully acknowledged.
文摘An operationally simple approach for the tandem synthesis of isoquinolines by the reaction of o-alkynylalde- hydes with ammonium bicarbonate via Ag-catalyzed 6-endo-dig ring closure is described. The reaction conditions and the scope of the reaction are examined, and a variety of substituted isoquinolines are prepared in moderate to excellent yields.
文摘Organic-inorganic MoO_(3)/PI(MoPI)composites were prepared using a simple one-pot thermal copolymerization method.The resulting composites exhibited enhanced photocatalytic activity for the selective oxidation of benzylamine to N-benzylidene benzylamine(N-BDBA)in ambient air under simulated solar light irradiation compared to pristine MoO_(3) or polyimide(PI).In particular,the MoPI composite with a 0.3:1 molar ratio of Mo to melamine,referred to as MoPI-0.3,demonstrated the best performance in the photo-oxidation of benzylamine,achieving a benzylamine conversion of 95%with a N-BDBA selectivity exceeding 99%after 3 h irradiation.The enhanced photocatalytic activity of the MoPI-0.3 catalyst was attributed to the formation of a direct Z-scheme heterojunction between MoO_(3) and PI,facilitating more efficient separation of the photoinduced electrons and holes.Additionally,the MoPI-0.3 composite maintained considerably high activity over four consecutive cycles,highlighting its good stability and recyclability.Furthermore,the MoPI-0.3 composite could photo-oxidize benzylamine derivatives and heterocyclic amines to their corresponding imines,demonstrating the universal applicability of this composite catalyst.
基金the Opening Project of Key Laboratory of Green Catalysis of Higher Education Institutes of Sichuan(Grant number:LZJ2101)the Fundamental Research Funds of China West Normal University(Grant number:19D038).
文摘Polyimide(PI) is an organic polymer material with good stability and diverse sources that has attracted widespread attention in the field of photocatalysis. In this study, a series of PI photocatalysts were synthesized by a thermal polymerization approach using pyromellitic dianhydride(PMDA) and various diamine monomers(melamine(MA), 4,4′-oxydianiline, and melem) as the precursors as well as different heating rates. The effects of the diamine precursor and heating rate on the structure, composition, morphology, and optical properties of the as-prepared PI materials were systematically investigated by various characterization techniques. The selective photo-oxidation of benzylamine was used as a model reaction to evaluate the photocatalytic activities of the resulting PI samples for the oxidation of amines to imines. The results revealed that the PI sample prepared using MA and PMDA as the precursors and a heating rate of 7 ℃/min(MA-PI-7) exhibited the best catalytic performance, with 98% benzylamine conversion and 98% selectivity for N-benzylidene benzylamine after 4 h of irradiation. Several benzylamine derivatives and heterocyclic amines also underwent the photo-oxidation reaction over the MA-PI-7 catalyst to afford the corresponding imines with good activity. In addition, MA-PI-7 exhibited good stability over four successive photocatalytic cycles.
基金the National Natural Science Foundation of China(No.20772068)the National Key Project of Scientific and Technical Supporting Programs of China(No.2006BAE01A01-5) for financial support
文摘Eleven new imine derivatives 6 containing 1H-1,2,4-triazole and thiazole rings were synthesized by the condensation of 5-((1H- 1,2,4-triazol-1-yl)methyl)-4-tert-butylthiazol-2-amine with various substituted benzaldehydes.The structures of the title compounds were characterized by ~1H NMR,MS and elemental analysis.The plant-growth regulatory activities of these compounds were evaluated.The primary bioassay results indicated that these target compounds exhibited promising plant-growth regulatory activities.
基金the National Natural Science Foundation of China(21878054)Project on the Integration of Industry and Education of Fujian Province(2018Y4008)+3 种基金Science and Technology Project of Fujian Educational Committee(JAT190051)Fuzhou University Testing Fund of precious apparatus(2020T008)Research Initiation Funding of Fuzhou University(GXRC-19051)the Award Program for Minjiang Scholar Professorship。
文摘A series of polymeric ionic liquids(PILs)used as effective heterogeneous catalysts for biodiesel production via esterification of free fatty acids(FFAs)were effectively prepared by the reaction of poly(ethylene imine)(PEI)polymers with different molecular weight and 1,3-propanesultone,followed by the further acidification with differential effective acids,i.e.H2SO4,CF3SO3H,CH3SO3H or p-toluenesulfonic acid(p-TSA).Ultrahigh acidity and catalytic performance were achieved and could be fine-tuned by simply adjusting the molecular weight of PEI and by further treatment of acids.Specifically,under the optimal conditions(i.e.reaction temperature was 70℃,reaction time was 2.0 h,catalyst dosage was 3.15%(mass),and alcohol/acid molar ratio was 14:1)acquired through the Box-BEHNKEN response surface methodology,a high oleic acid conversion of 98.42%could be obtained over the optimal PIL,PEI(70000)-PS-p-TSA.Additionally,our PILs also showed high generality for esterification of other FFAs,with general high conversion over 90%noted in each case even under much milder reaction conditions compared to other conventional catalysts.
基金supported the Ministry of Agriculture of the People’s Republic of China.
文摘Background:Ethoxyquin(EQ)is a common antioxidant which is widely used in animal feed.But the supplement of EQ in animal feed may lead to the residues of EQ and its major oxidation products:ethoxyquin quinone imine(EQI)and ethoxyquin dimer(EQDM)in animal tissue.Thus,it would pose potential health hazards to consumers.However,the method for the simultaneous determination of EQ,EQI and EQDM in animal tissues is currently not available,and the accumulation extend of these chemicals in animal tissues after EQ administration remains to be evaluated.Results:A gas chromatography-tandem mass spectrometry method was successfully developed for the simultaneous determination of EQ,EQI and EQDM in swine tissues.The quantitative limits of EQ,EQI and EQDM can achieve to 0.5,5.0 and 5.0μg/kg in swine tissues,respectively.The spiked-recovery ratios of the three analytes(5–2000μg/kg)were in the range of 64.7%–100.7%with relative standard deviations below 11.6%.Moreover,the utilization of this method for the analysis of actual swine tissue samples revealed that the application of commercial EQ additive in swine diet would produce the residues of all the three chemicals(EQ,EQI and EQDM)in fat,kidney,liver and muscle.Conclusions:The assay accuracy and precision of this GC-MS/MS method can meet the requirement of quantitative analysis.Meanwhile,the safety of EQ as a feed additive should be seriously considered with regard to food safety concerns since the oxidation product of EQ may have potential carcinogenicity.
文摘The addition of allyltrimethylsilane to tert-butanesulfinyl imines triggered by tetra-n-butylammonium fluoride (TBAF) in the presence of 4A molecular sieves has been studied, and homoallylsulfinamides were obtained in good yields with moderate to high diastereoselectivities.
基金support for this research was provided from the National Natural Science Foundation of China(No.30472075)the Excellent Ph.D.Dissertation Foundation of China(No.200367).
文摘Two novel C-nor-B-homo aconane-type diterpenes 4 and 5, featuring a unique eight-membered ring system, were obtained by the treatment of C-nor-C19-diterpenoid alkaloid 3 with HNO2 in 8% and 21% yields, respectively. Structures of these two compounds were established based on the combination of spectroscopic data, including HRESIMS, 1D and 2D NMR data. A olausible mechanism for the formation of 4 and 5 is also presented.
基金supported by the Shanghai Leading Academic Disciplines (Grant No.T0105)the Key Laboratory of Science & Technology of Eco-Textile (Donghua University), Ministry of Education of China
文摘The synthesis and properties of three kinds of hyper-dispersants are studied in this paper, which are non-terminated, carboxyl-terminated and polyethylene imine grafted poly(hydroxyl carboxylic acid) ester. The hyper-dispersants are synthesized by the materials of 12-hydroxy-stearic acid, stearic acid and polyethylene imine, which are used to improve the dispersion properties of nano titanium dioxide (nano-TiO2) in low-concentration resin solution system. The influences of hyper-dispersants on the viscosity and stability of the system are studied. It is found that polyethylene imine grafted hyper-dispersant has the best dispersion performance in nano-TiO2 dispersion system, and the optimal content of the hyper-dispersant is 4%.
基金Supported by the National Basic Research Program of China(No.2010B12606)
文摘Nine new a-aminophosphonate derivatives containing cyclopropane moiety have been synthesized via conventional and microwave irradiation methods under solvent- and catalyst-free condition. The structures of the title compounds have been confirmed by ^1H NMR, ^31p NMR FTIR, EI-MS and FTICR-MS. Their antifungal activities were evaluated in vivo and some of the compounds were found to exhibit excellent antifungal activities against Corynespora cassiicola, Pseudomonas syringae pv. Lachrymans, Pseudoperonospora cubensis and Sclerotinia sclerotiorum.
文摘Treatment of 3-acetylpseudaconie 6 and 3. 13-diacetylyunnaconitine 9 withNBS/acetone-H2O(2:1) at room temperature produced corresponding imine derivatives & and 10.respectively. in good yields. This is a novel simple and convenient method for preparation of theimine compounds.
基金Supported by the National Natural Science Foundation of China(21776258,21476207,91534113,21406199,21566013,21875220)Education Science Planning Project of Jiangxi Province(No.18YB243)the Program from Science and Technology Department of Zhejiang Province(2015C31042).
文摘A novel template-free oxalate route was applied to synthesize different mesoporous manganese oxides(amorphous manganese oxide(AMO),Mn5 O8,Mn3 O4,Mn O2)in the narrow temperature range from 350°C to 400°C by controlling the calcination conditions,which were employed as the efficient catalysts for the oxidative coupling of alcohols with amines to imines.The chemical and structural properties of the manganese oxides were characterized by the methods of thermogravimetry analysis and heat flow(TG-DSC),X-ray diffraction(XRD),nitrogen sorption,scanning electron microscope(SEM),transmission electron microscopy(TEM),X-ray photoelectron spectroscopy(XPS),H2 temperature-programmed reduction(H2-TPR),and inductively coupled plasma optical emission spectrometry(ICP-OES)techniques.The structures of different manganese oxides were confirmed by characterization.The M-350(AMO)presented the maximum surface area,amorphous nature,the lowest reduction temperature,the higher(Mn3++Mn4+)/Mn2+ratio,and the higher adsorbed oxygen species compared to other samples.Among the catalysts,M-350 showed the best catalytic performance using air as an oxidant,and the conversion of benzyl alcohol(BA)and the selectivity of N-benzylideneaniline(NBA)reached as high as 100%and 97.1%respectively at the lower reaction temperature(80°C)for 1 h.M-350 had also the highest TOF value(0.0100 mmol·mg-1·h-1)compared to the other manganese oxide catalysts.The catalyst was reusable and gave 95.8%conversion after 5 reuse tests,the XRD pattern of the reactivated M-350 did not show any obvious change.Lattice oxygen mobility and(Mn3++Mn4+)/Mn2+ratio were found to play the important roles in the catalytic activity of aerobic reactions.
基金This work was supported by the National Natural Science Foundation of China (No. 20425312)
文摘Many proline-catalyzed asymmetric addition reactions with ketones as substrates were assumed to involve a key intermediate, an enamine, produced by the condensation of proline and ketone. In this paper, the key intermediate enamines derived from L-proline and cyclohexanone (or acetone) as well as the corresponding oxazolidinone and imine tautomers have been investigated by means of density functional calculations at the B3LYP/6-311+G^** level. The predicted order of stability for these tautomers is oxazolidinones 〉 enamines 〉 imines in gas phase and oxazolidinones 〉 imines 〉 enamines in aprotic THF solvent. This prediction explains why enamine intermediate can not be observed experimentally. The predicted energy/enthalpy difference between the formal oxazolidinone structure and the zwitterionic imine structures is very small in THF solvent, suggesting the oxazolidinone-to-imine tautomerization can be readily induced in solvent. ^13C NMR chemical shifts of the oxazolidinone and imine structures have been computed and used to explain the experimental NMR spectra observed in oxazolidinone-to-imine tautomerization induced by protic solvent.
文摘1-Phenyl-1,3-butandione benzidine diketoimine 2a (C32H28N2O2, Mr = 472.56) was synthesized in high yield by the reaction of 1-phenyl-1,3-butandione with benzidine in absolute ethanol, and determined by X-ray structure analysis. It crystallizes in the orthorhombic system, space group P21/c with a = 7.9839(16), b = 12.910(3), c = 12.358(3)A, α = 90.00, β= 93.71(3),γ = 90.00°, V = 1271.1(4) A3, Z = 2, Dc = 1.235 g/cm^3,/1 = 0.077 mm^-1, F(000) = 500, the final R = 0.0717 and wR = 0.1187. It presents a linear centrosymmetric framework constituted by a linkage of benzidine as a bridge and two terminal 1-phenyl-1,3-butanedione moieties.
基金Dicle University Science and Technology Research Center(DUBTAM)Dicle University Scientific and Technological Research Council(DUBAP)with Grant Number:14–EZF–14 are gratefully acknowledged for their analysis and financial supports
文摘Boronic acid compounds with different substituted groups were handled to synthesize various ligands encoded as B1, B2, B3, B4, BS, B6, B7 and BS. B5 and B7 were tested for the cytotoxic activity against the prostate cancer cells and it was found that the cell viability of cancer cells was decreased while most of the healthy cells could still be viable. 5 μM solutions of B5 and B7 decreased the cell viability to 33% and 44%; whereas healthy cells were 71% and 95%, respectively, after treatment. Antimicrobial properties were explored against the bacterial and fungal microorganisms with B1, B5 and BZ The inhibition zones were evaluated for all boronic structures, and the growth inhibition zones were determined in a range of 7-13 mm diameter for different microorganism species. Staphylococcus aureus was the common micro- organism that three boronic compounds with imine ligands showed the activity. Antioxidant features of B2, B3, B4, B5, B6, B7 and B8 were investigated by different processes such as Beta-carotene bleaching (BCB), 2,2-diphenyl picryl hydrazyl (DPPH), 2,2″-azino-bis( 3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and CUPric reducing antioxidant capacity (CLIPRAC) methods. Significant antioxidant activity was achieved by the phenyl boronic based ligands and these compounds demonstrated as much activity as standards (α-Toc and BHT). In addition, all structures were applied properly without any decomposition during the experiments. They were rather stable both in aqueous media and solid state.
基金This study was fully funded and supported by Shahid Beheshti University of Medical Sciences(Research grant number.7026)The authors would like to acknowledge Mr.F.Rafraf and Mr.S.M.Foroutanfar for their valuable supports in design of encapsulator device and the graphical parts of this project.
文摘In past decades, alginate-based multilayer microcapsules have been given important attention in various pharmaceutical investigations. Alginate-poly l lysine-alginate(APA) is studied the most. Due to the similarity between the structure of polyethyleneimine(PEI) and poly-L-lysine(PLL) and also lower price of PEI than PLL, this study was conducted to compare the efficacy of linear(LPEI) and branch(BPEI) forms of PEI with PLL as covering layers in fabrication of microcapsules. The microcapsules were fabricated using electrostatic bead generator and their shape/size, surface roughness, mechanical strength, and interlayer interactions were also investigated using optical microscopy, AFM, explosion test and FTIR, respectively. Furthermore, cytotoxicity was evaluated by comparing the two anionic final covering layers alginate(Alg) and sodium cellulose sulphate(NCS) using MTT test. BPEI was excluded from the rest of the study due to its less capacity to strengthen the microcapsules and also the aggregation of the resultant alginate-BPEI-alginate microcapsules, while LPEI showed properties similar to PLL. MTT test also showed that NCS has no superiority over Alg as final covering layer. Therefore, it is concluded that, LPEI could be considered as a more cost effective alternative to PLL and a promising subject for future studies.
基金The authors thank the National Natural Science Foundation of China (Grant No. 29972018) for financial support.
文摘A series of aromatic imines were reduced to corresponding amines in excellent yields by 2-phenyl-N. N-dimethylbenzimidazoline (PDMBI) photochemically in the presence of magnesium perchloride (Mg(ClO4)(2)). A Mg2+ mediated photoinduced electron transfer mechanism was proposed.
文摘An unexpected tricyclic compound 2,3,3a,4,5,9b-hexahydrophenylfuro[3.2-c] quinoline 4 and its aromatized product 6 were obtained when the cycloaddtion of imine 1 and substituted norbornene 2 was carried out in THF with a catalytic amount of boron trifluoride. The structures of the products were determined by spectral data and the mechanism of reaction was substantiated by the imitation reaction.