Two complexes, Co(Hbim)2(NCS)2(Hbim=benzimidazole)(1) and [Cu(Hbzt)SCN] n(Hbzt=benzothiazole) (2) were synthesized by the same synthesis method and characterized by elemental analysis, infrared spectroscopy(IR), thermogravimetric analysis(TGA), X-ray powder diffraction(XRPD) and single-crystal X-ray diffraction. The results from the single-crystal X-ray diffraction indicate that complex 1 is zero-dimensional(0D) framework and complex 2 is 2-dimensional(2D) framework. In complex 2, the 3-dimensional(3D) supermolecular architecture was built up by means of π-π stacking interaction, and two helical chains existed in its structure. The luminescence properties and the magnetic properties of the two complexes were investigated.
The lowest triplet energy levels of the six ligands(T) were determined to be 22989 cm−1[1,3-bis-(1′-phenyl-3′-methyl-5′-pyrazolon-4′)-1,3-propanedione, BPMPTD], 23148 cm−1[1,4-bis-(1′-phenyl-3′-methyl-5′-pyrazolon-4′)-1,4-butanedione, BPMPBD], 23419 cm−1[1,5-bis-(1′-phenyl-3′-methyl-5′-pyrazolon-4′)-1,5-pentane-dione, BPMPPD], 23310 cm−1[1,6-bis-(1′-phenyl-3′-methyl-5′-pyrazolon-4′)-1,6-hexanedione, BPMPHD], 21978 cm−1[1,9-bis-(1′-phenyl-3′-methyl-5′-pyrazolon-4′)-1,9-nonanedione, BPMPND] and 21930 cm−1[1,10-bis-(1′-phenyl-3′-methyl-5′-pyrazolon-4′)-1,10-decanedione, BPMPDD], respectively. It was explained satisfactorily that the six ligands are more efficient for sensitizing the luminescence of Tb3+ than that of Eu3+ at room temperature, and the order of the luminescent intensities for the Tb3+ complexes is explained by the relative energy gap between T and 5 D J of Tb3+ or Eu3+. As a conclusion, when 2700 cm−1<ΔE(T-5 D 4)<3000 cm−1, the luminescent intensity of the Tb3+ complex is the strongest. This means that the lowest triplet energy level of the ligand is a chief factor to dominate RE3+ luminescence.
Two new compounds, [ErAg(INA)2(C2O4)]·2H2O(1)(HINA=nicotinic acid) and [Tb0.8Y0.2Ag2(IN)4·(H2O)5]·NO3·2H2O(2)(HIN=isonicotinic acid), based on the {2} building units, have been hydrothermally synthesized and characterized by single-crystal X-ray diffraction, infrared spectroscopy, thermal analysis and powder X-ray diffraction(PXRD). Single-crystal X-ray diffraction data reveal that both compounds crystallized in the low-symmetry triclinic space group P$\mathop {\rm{1}}\limits^{\rm{ - }} $. Compound 1 is a 3D heterometallic coordination framework based on {Er2} clusters, oxalate ligands and bridging [Ag(INA)] linkers, while compound 2 consists of 0D [Tb0.8·Y0.2Ag2(IN)4(H2O)5]2 subunits that give a 3D supramolecular structure through hydrogen bond interaction. The photoluminescent properties of both compounds(1 and 2) were studied.
Al-pillared mesoporous montmorillonite was facilely synthesized from concentrated Al13 solution obtained by vacuum concentrating-ultrasonic pillaring strategy. Concentrated Al13 solution could reduce the process of pillare and increase pillaring efficiency. The absolute value of layer distance could be increased by 0.96 nm via concentrated Al13 solution pillare. 27Al NMR indicates that Al Keggin ions of concentrated Al13 are arranged in a more regular way by vacuum concentrating method. The Al-pillared mesoporous montmorillonite from concentrated Al13 solution has bigger specific surface area and even pore size distribution which were characterized by X-ray diffraction(XRD) and nitrogen adsorption measurement. Furthermore the catalytic activity of Al-pillared montmorillonite loaded Ni and Mo catalysts was tested by the hydrodesulfurization of thiophene. The thiophene conversion reached 77.5%, which was higher than the corresponding value reported in the literature.
A hybrid membrane consisted of aminated graphene and Ag nanoparticles(Ag NPs) was prepared on the surface of glassy carbon electrode(GCE) by cyclic voltammetry(CV) with aminated graphene(GR-NH2) as matrix for immobilizing Ag NPs. The morphology and electrochemical properties of this hybrid membrane were characterized by scanning electron microscopy(SEM) and CV, respectively, and on this membrane, the voltammetric behaviors of epinephrine(EP) were studied in detail. The membrane exhibited excellent eletro-catalytic activities for the redox of EP, and could resolve the electrochemical response of EP and uric acid(UA) into two oxidation peaks. The peak current of EP was linear with its concentration in the ranges of 0.916–18.3 μmol/L and 18.3–184 μmol/L. The detection limit was 2.0 nmol/L(S/N=3). The proposed modified electrode retained the advantages of easy fabrication, high sensitivity and good repeatability for the determination of EP.
A laboratory-made tumor cell detection device was fabricated based on both surface plasmon resonance imaging(SPRi) and image processing. In this device, a gravity-induced flow injection chip(gFIC) was exploited to replace a pump. Also two charge coupled devices(CCDs) were used to detect HepG2 cells by SPRi and image processing, respectively. The results of two CCDs are associated. Protein A was used to modify the sensing surface. The inlet angle was carefully adjusted for the device to get an enhanced image. In the test, the contrast among cell solutions at different concentrations can be easily distinguished. The other CCD using image processing can tell false-positive in some degree. This detection is label-free, real time, and precise.
A new hybrid organic-inorganic monolithic cartridge was synthesized and used as the selective sorbent for the extraction and purification of quercetin and myricetin from Chamaecyparis obtusa via a solid-phase extraction method. The morphology of the monolithic material was examined by field emission-scanning electron microscopy and a Brunauer-Emmett-Teller(BET) test. The adsorption capacity of the obtained material for quercetin and myricetin was investigated by fitting the adsorption data to four different adsorption equations, of which the Langmuir-Freundlich isotherm was selected as the most suitable model. Under optimized conditions, good calibration curves were observed at nine concentrations ranged from 0.5 μg/mL to 100.0 μg/mL of quercetin and myricetin. The extraction recovery ranged from 74.5% to 84.6% and the inter- and intra-day relative standard deviations were <6%. This type of hybrid monolith has potential for the separation and purification of bioactive compounds from natural plant extracts.
Transitions among various molecule states and conformational changes of bovine insulin were investigated under different denaturing conditions by means of fluorescence phase diagrams, fluorescence quenching, 1-anilinonaphthalene-8-sulfonate(ANS) binding assay and circular dichroism(CD) spectra. In both guanidine hydrochloride( GuHCl)- and urea-denatured procedures, the spatial structure of insulin molecules changed from ordered states to relative unordered ones with the increasing of denaturant concentration. The GuHCl-denatured process followed a four-state model, for there were two intermediates existed in 2.0 and 6.0 mol/L GuHCl, respectively. Intermediate I1 is more compact than the normal protein. And intermediate I2 has lost most of the secondary structures. When GuHCl concentration was above 6.0 mol/L, the fluorophores originally existed in the internal of insulin molecules would expose to the surface. However, the urea-denatured process followed a three-state model, only one intermediate existed in 2.5 mol/L urea. During the urea-denatured procedure, the fluorophores originally existed in the internal of insulin molecules didn’t expose to the surface.
Two series of novel anthranilic diamides containing oxime ester and diacylhydrazine moieties were designed and synthesized. Their structures were characterized by melting points, 1H NMR, 13C NMR and high resolution mass spectrometry(HRMS). The single crystal structure of compound 7e was determined by X-ray diffraction and their evaluated insecticidal activity against oriental armyworm(Mythimna separata) indicates that some of the compounds exhibited moderate insecticidal activities. Among the 20 compounds, 6a and 6b show 100% larvicidal activity against Mythimna separate Walker at the test concentration of 100 mg/L.
A chiral Lewis base organocatalyzed enantioselective hydrosilylation of α-keto ketimines was investigated. The reactions afforded various enantioenriched α-amino ketones with good yields(up to 95%) in moderate to good enantioselectivities(up to 98% e.e.). Furthermore, one of the products was reduced to a chiral 1,2-amino alcohol. Following cyclization of it with triphosgene generated a cannabinoid receptor 1(CB1) inhibitor with good diastereoselectivity.
Based on the 1,3-dipolar cycloaddition of azomethine ylide generated in situ from aldehyde and sarcosine attached to C60, two novel benzo-15-crown-5/C60 dyads with a different linking chain in each were designed and synthesized in yields of 30% and 38%, respectively. It was found that their UV-Vis absorption spectra could be regulated hypsochromically by metal ions complexed. The long and soft linking chain was favorable for cooperate interaction of crown ether unit and C60 unit.
A p-tert-butylthiacalix[4]arene-based polydentated ligand with four Schiff base units on 1,3-alternate position at lower rim has been prepared in three steps, which coordinated to copper ion to form a novel dicopper complex. The structures of the polydentated thiacalixarene ligand and copper complex were fully characterized by spectroscopy and X-ray single crystal diffraction method.
A facile 7-step procedure for the synthesis of enantiomerically pure 1-(5-bromo-2-chlorophenyl)-1-(4-ethoxyphenyl)ethanes[(R)-2 and(S)-2] that started from (5-bromo-2-chlorophenyl)(4-ethoxyphenyl)methanone 3 was developed. The key step was the resolution of 2-(5-bromo-2-chlorophenyl)-2-(4-ethoxyphenyl)acetic acid 6 by crystallizations of its L- and D-menthyl esters 7 and 8 from petroleum ether to give optically pure enantiomers 9 and 10, respectively. The absolute configurations of the products were unambiguously determined by single-crystal X-ray diffractions of four key intermediates, 9, 10, 13 and 14. This procedure is characterized by inexpensiveness, scalability and ability to produce two individual enantiomers of a diarylethane with unambiguously determined absolute configurations and high enantiomeric purities.
In an attempt to develop potent and selective anticancer agents, we designed and synthesized a series of novel bis(morpholino-1,3,5-triazine) derivatives bearing aylmethylene hydrazine moiety and evaluated their cytotoxicity, in vitro, against H460(non-small-cell lung cancer), HT-29(human colorectal cancer) and MDA-MB-231(human breast cancer) cell lines. The pharmacological results indicate that all the compounds exhibit enhanced cytotoxicity than BMCL-200908069-1, and six target compounds(7e, 7h, 7j, 9a, 9b, 9c) were superior to PAC-1 against all the tested cancer cell lines. The most active compound 7j, with IC50^(inhibitory concentration 50%) values of 0.75, 0.34 and 0.60 μmol/L against HT-29, H460 and MDA-MB-231 cancer cell lines, was 39-, 28-, and 60-fold more potent than BMCL-200908069-1(29.24, 9.52 and 36.21 μmol/L), respectively.
An efficient method for the bromoamidation of β,β-dicyanostyrene derivatives with N-bromoacetamide (NBA) was developed. This protocol provides a convenient process to convert β,β-dicyanostyrene derivatives into the vicinal haloamines in excellent yields(up to 99%) at room temperature in the presence of anhydrous K3PO4 as a catalyst without the protection of the inert gaseous in CH2Cl2. A total of 11 examples were investigated and all the products showed the regionspecific feature. Based on the observation of different activities for the different substrates involving the electron-rich or electron-deficient β,β-dicyanostyrenes, a possible Michael addition mechanism was proposed.
Proteome profiling was performed on Arabidopsis plant exposed to cold stress at 4 °C for 24 h in an attempt to explore the mechanisms of plant climate adaptation. The polyethylene glycol(PEG) fractionation protocol developed in this lab was used to identify as many differentially expressed low-abundance proteins as possible. In comparison with those of the biological controls, 67 protein spots with at least two-fold difference in expression were identified for the plant exposed to cold temperatures; and from these spots, 50 proteins were successfully identified by matrix-assisted laser desorption/ionization time of flight mass spectrometry(MALDI-TOF MS). Bioinformatics studies on these proteins show that 57.8% of these proteins were localized in the chloroplast. Of these proteins, 8 ones have functions in photosynthesis, including glycine hydroxymethyltransferase, Rubisco large subunit, Rubisco activase, PSBO2, fructose-1,6-bisphosphate aldolase, NADP-dependent malate dehydrogenase, sedoheptulose bisphosphatase and photosystem II reaction center PsbP family protein, suggesting that photosynthesis is greatly affected by cold stress. The identified proteins were validated by quantitative real-time polymerase chain reaction(qPCR). Taken together, our results suggest that the chloroplast might also act as a cold stress sensor and that photosynthesis-related proteins may play important roles in cold acclimation for Arabidopsis.
Chromium oxides supported on TiO2 showed good activity for the selective catalytic reduction of NO by NH3. The catalytic activity of Cr2O3-SO4 2−/TiO2 catalyst was greatly enhanced by the addition of SO4 2− into TiO2 support. The catalyst surface properties were characterized with NH3-TPD(temperature programmed desorption) and H2-TPR(temperature programmed reduction). The sulphate on the catalyst surface could enhance the acidity and redox of the catalyst obviously. The reaction mechanism on this catalyst was researched in detail by in situ diffuse reflectance Fourier transform infrared(FTIR) spectroscope. Eley-Rideal and Langmuir-Hinshelwood mechanism existed simultaneously for selective catalytic reduction(SCR) reaction of NO over Cr2O3-SO4 2−/TiO2 catalyst.
Ru-B/γ-Al2O3 catalyst was prepared by reductant impregnation method, which was applied in the selective hydrogenation of ethyl 1H-indole-2-carboxylate for producing ethyl 2,3,3a,7a-tetrahydro-1H-indole-2-carboxylate with hydrogen as reductant. Furthermore, we discussed the influences of substrate concentration, reaction solvent, hydrogenation temperature, initial hydrogen pressure and reaction time on the catalytic performance of the as-prepared catalyst. The obtained Ru-B/γ-Al2O3 catalyst showed a high-efficiency for the selective hydrogenation of ethyl 1H-indole-2-carboxylate(>99% conversion and selectivity) in i-propanol used as solvent at a concentration of 10%(mass fraction) of ethyl 1H-indole-2-carboxylate, a pressure of hydrogen of 6 MPa and a reaction temperature of 373 K.
Esterase BioH, which is obligatory for biotin synthesis in Escherichia coli, was found to exhibit a promiscuous ability to catalyse Aldol and Knoevenagel reactions with moderate to good yields. The reaction conditions including organic solvent, molar ratio of ketone to aldehyde, enzyme amount, and reaction time were investigated to evaluate the effect of different reaction conditions on yield. Target compounds were afforded in the best yield of 91.2% for Aldol reaction and 54.7% for Knoevenagel reaction. In addition, because the enzyme could be prepared with a low cost, this protocol could provide an economic route to conduct Aldol and Knoevenagel reactions, which expand the field of enzymatic promiscuity.
Ionic liquid, 1-butyl-3-methylimidazolium acetate(BMImAc), was used in the electrochemical reduction of nitrobenzene. The electro-reduction of nitrobenzene on platinum electrode was studied by cyclic voltammetry(CV), in situ Fourier transform infrared(FTIR) spectroscopy and constant-potential electrolysis. The experimental results show that electrochemical reduction process of nitrobenzene was controlled by diffusion, the main reduction product was azobenzen at −1.45 V, and the influences of scan rate and temperature on the electrochemical behaviors were obviously. A reduction mechanism of nitrobenzene in an ionic liquid was a probable ‘nitrobenzene→nitroso-benzene→azobenzene→aniline’ main reductive reaction route.
Integrase(IN) plays an essential role in the process of HIV-1 replication. IN inhibitors of diketo acid derivatives( DKAs) were analysed by the Comparative Molecular Field Analysis(CoMFA) and Comparative Molecular Similarity Induces Analysis(CoMSIA) methods. A set of 42 compounds were randomly selected as the training set(35) and test set(7). Firstly, a good pharmacophore(goodness of hit=0.787) was obtained and used to align ligands. Then, predictive models were constructed with the CoMFA and CoMSIA methods based on the pharmacophore alignment. As a result, the CoMSIA method yielded the best model with an r 2 of 0.955 and a q 2 of 0.665, which can predict the activities of the tested DKAs very well(r 2=0.559). Finally, DKAs were docked into IN, and the predicit modes were superimposed on the contour maps obtained from the best CoMSIA model. The superimposed maps gave a visualized and meaningful insight into the inhibitory behaviors, providing significantly useful information for the rational drug design of anti-IN agents.
Flower-like manganese wad(MW) with high activity was synthesized via ultrasonic-assisted redox reaction of sole manganese salt MnO4 −. MW was characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM) and X-ray photoelectron spectroscopy(XPS). The experimental results indicate that the maximum decolorization rate of Congo red(CR) reached above 95% within 15 min in a wide pH range from 2.0 to 6.0. Results also show that MW has excellent decolorization performance for azo dye CR which implies potential application for removing dye pollutants from industrial effluents.
Aldehyde group-functionalized [Ru(bpy)2L](PF6)2 catalyst was prepared and immobilized onto the mesoporous silica nanoparticles to act as a heterogeneous catalyst for the selective oxidation of thioanisole to methyl phenyl sulfoxide under visible light. The heterogeneous catalyst can be easily recovered by simple centrifugation without chemical treatment, exhibiting comparable catalytic efficiency with homogeneous ones and no decrease in catalytic efficiency after at least 5 cycles.
Microfiber reinforced nanofiber films were prepared with the help of two nozzles technology. We designed a new device via placing two nozzles on the opposite sides of a rolling cylinder, with a piece of thin insulation board with a certain size of hole in the middle part installed to accommodate the cylinder so as to form two entirely independent electric fields. Playing the role of support, microfiber may be favorable for enhancing the mechanic performance of the nanofiber. Compared with that of single nanofiber, the tensile strength of the composite micro/nanofiber prepared by this method has been increased by a factor of 4.5. After the further improvement of the fiber orientation, the tensile strength is 7.96 times that of non-oriented composite micro/nanofibers film, 30 times that of the single nanofiber film.
Flower-like aggregates composed of (4.0±0.8) nm palladium(Pd) nanoparticles were prepared via ultrasonics in the palladium(II) chloride(PdCl2) H2O/EtOH(5/1, volume ratio) solution with the addition of a quantity of poly(vinyl pyrrolidone)(PVP) and sodium dodecyl sulfonate(SDS). The morphologies, crystal structures and the optical properties of the flower-like Pd nanostructures were characterized by X-ray diffraction(XRD). X-ray photoelectron spectroscopy(XPS). scanning electron microscopy(SEM). transmission electron microscopy(TEM). selected area electron diffraction(SAED) and UV-visible absorption spectroscopy, respectively. The mechanism of sonochemical reduction of Pd(II) ions was also investigated. The results show that the molar ratio of PVP to SDS affected the formation of the flower-like aggregates of Pd nanoparticles. Moreover, the electrocatalytic properties of Pd aggregates modified glassy carbon electrode for ethanol oxidation were also investigated by cyclic voltammetry(CV). This material exhibits remarkable electrocatalytic activity for ethanol oxidation in 1 mol/L KOH and appears as a promising candidate to be applied in direct ethanol fuel cells.
In order to improve the therapeutic index and reduce the side effects of As2O3 so as to expand its clinical utility to solid tumors, As2O3-loaded polylactic acid(PLA)/magnetic nanoparticles(PAMNs) were prepared and the preparation conditions were optimized by the improved double emulsion solvent-evaporation method to obtain as a drug delivery system with a high As2O3 encapsulation efficiency and homogeneous nanosized particles. Successful loading of magnetic nanoparticles into the nanoparticles was confirmed by Fourier transform infrared(FTIR) spectroscopy. The drug loading, encapsulation efficiency and releasing properties of As2O3 in PAMNs were investigated by atomic fluorescence spectrometer analysis. Subsequently, the in vitro antitumor efficacy of free As2O3 and As2O3-PAMNs against SMMC-7721 cell line was investigated. Finally, confocal fluorescence microscopy was conducted to reveal the celluar uptake of As2O3-loaded PAMNs by SMMC-7721 cell line.
A newly synthesized aromatic sulfonate compound, complex 2 with formula of K2[H3COOC-C6H3(SO3)2]·2H2O(methyl 3,5-disulfo-benzoate dipotassium dihydrate) was synthesized and characterized by elemental analysis, infrared(IR) spectrometry, nuclear magnetic resonance(NMR) and crystal structure measurement. Single-crystal X-ray diffraction(XRD) revealed that complex 2 crystallized in the triclinic system with space group $P_{\bar 1}$. Complex 2 was used as nucleating agent for poly(L-lactide)(PLLA). The crystallization of PLLA with powder of complex 2 was investigated by means of differential scanning calorimetry(DSC) and polarized optical microscopy (POM). The results prove that complex 2 was effective as nucleating agent for PLLA. It could accelerate crystallization by reducing the induction time and increasing the density of nuclei in the crystallization process. The half-time of crystallization(t 0.5) for pure PLLA was about 8 times longer than that of PLLA sample with 1.0%(mass fraction) of complex 2.
Poly(n-alkyl acrylate) with long side groups, namely, poly(lauryl acrylate)(PLA) was synthesized by reversible addition-fragmentation chain transfer(RAFT) polymerization, and the trithioester terminal groups were converted to thiol by reducing reaction. Grafting of the obtained polymer onto nano-silica modified with 3-(methacryloxy)propyl-trimethoxysilane(SiO2-MPS) was conducted by thiol-ene ‘click chemistry’. PLA was characterized by proton nuclear magnetic resonance(1H NMR) and gel permeation chromatography(GPC). Fourier transform infrared(FTIR) spectrometry and thermogravimetric analysis(TGA) were used to demonstrate the grafting reaction, and the grafted hairy nano-silica(SiO2-g-PLA) was viewed under a transmission electron microscope(TEM). According to TGA, grafting ratio and grafting density of SiO2-g-PLA are 30.27% and 0.013 chain/nm2, respectively. The static water contact angle of SiO2-g-PLA is (80.10±2.97)°, which ensures its hydrophobicity. Dispersion experiment was carried out to confirm its dispersibility in mixed solvents, indicating its potential application in coatings or composites.