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Herein two unprecedented octanuclear Co8 clusters are presented, [Cl@Co8 (TEOA)4(CH3CN)Cl3] (1) and [S@Co8(DEOA)6(NCS)2] (2) (H3TEOA = triethanolamine, H2DEOA = diethanolamine), in which tetrahedral μ4-chloride and in situ generated octahedral μ6-sulfide are used as templates. In spite of them being derivatives of cubes, eight Co atoms in 1 consist of two co-centered tetrahedra of different sizes, whereas in 2 they appear as a rhombohedron formed via elongating a cube along the C3-axis direction. Strong intra-cluster antiferromagnetic interactions were found.

The reactions of diphosphine ligands and nitrogen-containing ligands with Cu(I) salts in the mixed solvents of methanol (MeOH) and dichloromethane (CH2Cl2) generated the corresponding complexes, {[Cu(dppbe)(Bphen)](ClO4)·2CH3OH}n (1), {[Cu2(dppe)(dmp)2(CN)2]·2CH3OH}n (2), {[Cu2(dppb)(dmp)2I2]·2CH3OH}n (3), [Cu(POP)(C16H6N6)]I (4), {[Cu(POP)(C16H6N6)](SCN)}n (5), [Cu(xantphos)(bpy)](ClO4) (6) and {[Cu(xantphos)(bpy)](CF3SO3)}n (7) {dppbe = 1,2-bis(diphenylphosphanyl)benzene, dppe = 1,2-bis(diphenylphosphino)ethane; dppb = 1,4-bis(diphenylphosphino)butane, POP = bis[2-(diphenylphosphino)phenyl]ether, xantphos = 4,5-bis (diphenylphosphio)-9,9-dimethylxanthene, Bphen = 4,7-diphenyl-1,10-phenanthroline, dmp = 2,9-dimethyl-1,10-phenanthroline, C16H6N6 = [2,3-f]-pyrazino-[1,10]phenanthroline-2,3-dicarbonitrile, bpy = 2,2′-bipyridine}. These complexes were all characterized by single-crystal X-ray crystallography, elemental analysis, IR, 1H NMR spectroscopy, luminescence and THz spectroscopy. Complexes 1 and 2 consist of 1D infinite zigzag chain structures which are linked by hydrogen bonds, while complexes 3, 5 and 7 have 2D topological architectures which are connected by hydrogen bonds, complex 4 has an annular structure and complex 6 is a mononuclear structure. The types of hydrogen bonds, choice of solvents and coordination modes of the ligands are of importance in defining the structural and topological features of the resulting networks. Furthermore, complexes 1–7 exhibit interesting luminescence in the solid state at room temperature. Complexes 1–3 can act as yellow luminophores, complex 4 acts as a red luminophore, complex 5 acts as an orange luminophore and complexes 6–7 act as green luminophores. Their terahertz spectra show more accurate characteristics of their structures.

A ratiometric fluorescent probe (DICX) based on Forster resonance energy transfer (FRET) system for hypochlorous acid (HOCl) was developed, in which coumarin moiety was connected to rhodamine by monothio-bishydrazide linker. DICX could fast respond to HOCl under acidic condition and showed high selectivity and sensitivity toward HOCl over other reactive oxygen species, reactive nitrogen species, and ions. The FRET energy transfer efficiency is very high (93.75%). Moreover, DICX could target lysosome and could be suitable for sensing exogenous and endogenous HOCl in living cells.

As one of the reactive oxygen species, hypochlorous acid (HOCl) may be associated with various diseases. To understand the roles of HOCl in living organism, fluorescent probes for imaging HOCl in living systems have been developed fast in recent years owing to their high selectivity, excellent sensitivity and spectral resolution. In this review, we summarized and highlighted the recent advances in the development and application of HOCl fluorescent probes. This review is focused on the detection mechanisms of probes for HOCl. According to the various recognition groups, we divided the HOCl fluorescence probes into five parts and discussed detection mechanisms, respectively.

The efficient and flexible syntheses of 5,8-disubstituted indolizidine poisonous-frog alkaloids is described using a highly stereoselective Michael-type conjugate addition reaction as the key step. In this work, syntheses of the 5,8-disubstituted indolizidine poisonous-frog alkaloids (–)-231C, (–)-221I and the proposed structure for (–)-193E are reported.

Five novel silver(I) complexes and two copper(I) phosphine complexes containing the bis[2-(diphenylphosphino)phenyl]ether ligand were synthesized and structurally characterized. Treatment of AgX/CuX and the bis[2-(diphenylphosphino)phenyl]ether with N^N ligands afforded the silver(I) or copper(I) complexes {[Ag2(POP)2(dpa)(H2O)2](dpa)(ClO4)2}n (1), {[Ag(POP)(dpp)](ClO4)}n (2), [Ag2(POP)2(4,4′-bipy)(CH3CN)2](CF3SO3)2·CH3CN (3), {[Ag(POP)(dpe)](CF3SO3)·CH3CN}n (4), {[Ag2(POP)2(dpe)(H2O)2](dpe)(BF4)2}n (5), [Cu(POP)(bpy)](BF4) (6) and [Cu2(POP)2(4,4′-bipy)](CF3SO3)2·4CH3CN (7) {POP = bis[2-(diphenylphosphino)phenyl]ether; dpp = 1,3-bis(4-pyridyl)propane; dpa = 1,2-bis(4-pyridyl)ethane; dpe = 1,2-bis(4-pyridyl)ethene; 4,4′-bipy = 4,4′-bipyridine; bpy = 2,2′-bipyridine}. These complexes are all characterized by IR, elemental analysis, X-ray diffraction, luminescence, 31P NMR and 1H NMR spectroscopy. Complex 5 has an irregular (6,3) network structure connected through hydrogen bonds between the C–H groups of aromatic rings and anions; complexes 1 and 2 are of 2D topological architectures which are linked by hydrogen bonds; complex 4 is of a 1D infinite zigzag chain structure formed by the bridging ligand dpe; complexes 3 and 7 are of dinuclear structures and complex 6 is of mononuclear structure. The choice of solvent and the type and coordination modes of the bipyridine derivatives are of importance in defining the structural and topological features of the resulting networks. In addition, the complexes 1–7 exhibit interesting luminescence in the solid state at room temperature. At the same time, we also studied the terahertz spectrum which provided some new informations of these complexes.

C58H56Cu2N6O2P2, monoclinic, P21/n, a = 12.0546(9) Å, b = 13.1669(10) Å, c = 16.7151(12) Å, β = 101.845(2)°, V = 2596.6(3) Å3, Z = 4, R gt(F) = 0.0539, wR ref(F 2) = 0.1431, T = 293(2) K.

Studies showed that the intravascular pH of neutrophils fell to 4.5–5.0 with stimulation for a few minutes. Under this condition, myeloperoxidase was activated to catalyze H2O2 and Cl− to form hypochlorous acid (HOCl). Therefore, it is of significance to develop fluorescence probes for sensing HOCl in acid conditions. In this work, we reported a ratiometric probe CRSH based on a fluorescence resonance energy transfer (FRET) platform for detecting HOCl under acid conditions. Probe CRSH exhibited excellent sensitivity, high selectivity and a rapid response toward HOCl and is suitable for imaging endogenous HOCl in living cells.

The development of novel methods to obtain biofuels and chemicals from biomass has been an immediate issue in both academic and industrial communities. The present work introduces a new route to synthesize 5-hydroxymethyl furfural (5-HMF) in a one-vessel system through a tandem pathway involving decrystallization, depolymerization and conversion of microcrystalline cellulose (MCC) in a molten hydrate solution. A 71.62 wt% ZnCl2 aqueous solution was employed as the reaction media and methylisobutylketone (MIBK) as the extracting solvent in the reaction system. A yield of 80.6 mol% of 5-HMF was obtained at 150 °C with a HCl concentration of 0.2 mol L−1 in the solution for 40 min. The aqueous phase can be reused without significant loss of catalytic activity.

A simple ratiometric probe (Naph-Rh) has been designed and synthesized based on a through-bond energy transfer (TBET) system for sensing HOCl. In this probe, rhodamine thiohydrazide and naphthalene formyl were connected by simple synthesis methods to construct a structure of monothio-bishydrazide. Free probe Naph-Rh showed only the emission of naphthalene. When probe Naph-Rh reacted with HOCl, monothio-bishydrazide could be converted into 1,2,4-oxadiazole, which not only ensured that the donor and the acceptor were connected with electronically conjugated bonds, but also resulted in the spiro-ring opening and the emission of rhodamine. Therefore, a typical TBET process took place. The probe possessed high-energy transfer efficiency and large pseudo-Stokes shifts. As the first TBET probe for HOCl, Naph-Rh showed excellent selectivity and sensitivity toward HOCl over other reactive oxygen species (ROS)/reactive nitrogen species (RNS), and could respond fast to a low concentration of HOCl in the real sample. In addition, the probe was suitable for imaging HOCl in living cells due to its real-time response, excellent resolution, and reduced cytotoxicity.

Three new labdane-type diterpenoids, callicapene M3-M5 (1–3) were isolated from the Callicarpa macrophylla Vahl. Their structures were identified by spectroscopic method. The isolated compounds were evaluated for inhibitory activity on NO production in LPS-activated RAW 264.7 macrophage cells by using MTT assays. Compounds 1–3 showed potent inhibitory activity, with IC50 value of 48.15, 46.31 and 38.72 μM respectively.

This work describes the synthesis and adsorption behavior of Fe 3 O 4 magnetic nanoparticles (MNPs) modified with 3-glycidoxypropyltrimethoxysilane (GPTMS) and poly-lysine (P-Lys). The magnetic nanoparticles were characterized by infra-red spectra, transmission electron microscopy, X-ray diffraction, thermogravimetric analysis and X-ray photoelectron spectroscopy. To understand the adsorption mechanism of the MNPs, we investigated anionic dye uptake capacity of Fe 3 O 4 @GPTMS@P-Lys as a function of contact time, dye concentration and pH. The MNPs could effectively remove anionic dyes including methyl blue (MB), orange I (OR-I), amaranth (AM) and acid red 18 (AR-18) from water solution. Furthermore, the improved adsorbent showed convenient separation and efficient reusability, and enhanced the adsorption capacity for anionic dyes.

Chlorophorus caragana (Coleoptera: Cerambycidae) is a trunk borer that feeds on Caragana shrubs in the desert. There are five species of Caragana plant in the distribution area of Ch. caragana. We investigated damaged Caragana plants in the field. Olfactory responses of female Ch. caragana to plants and identified volatile compounds from Caragana plants were further evaluated. Caragana davazamcii was severely damaged in the field, followed by Caragana microphylla. No damage was found to the other three species. Behavioral experiments showed that C. davazamcii, C. microphylla, and Caragana korshinskii were attractive to female insects. Caragana ordosica could repel and avoid female insects. Caragana brachypoda had no effect on the orientation behavior of female insects. Seventy volatile components were identified from the Caragana plants, and (Z)-β-ocimene, 1,3-pentadiene, (Z)-3-hexenyl acetate, perillene, chrysanthenone, and limonene were the most abundant volatiles identified from the Caragana plants. Th...

Based on density functional theory (DFT) calculations, we investigate the spin-related properties of spinless-hole injected organic molecule pentacene (Pc). DFT calculations reveal that there is spontaneous spin polarization in Pc when spinless-hole is injected. The charge-induced magnetic moment of Pc increases linearly with the increasing of the extra hole charge amount and its maximum can be up to 1 μB per injected spinless-hole per Pc molecule. The magnetic moment is expected due to the injected unpaired charge. The injected hole will preferably fill the spin-splitted carbon p z orbitals, which makes the Pc molecule spin polarize.

A novel compound, 2-(1,5-diphenyl-4,5-dihydro-1H-pyrazol-3-yl)phenyl acrylate (probe L), was designed and synthesized as a highly sensitive and selective fluorescent probe for recognizing and detecting glutathione among cysteine, homocysteine and other amino acids. The structures of related compounds were characterized using IR, NMR and HRMS spectroscopy analysis. The probe is a non-fluorescent compound. On being mixed with glutathione in buffered EtOH:PBS=3:7 solution at pH 7.4, the probe exhibited the blue emission of the pyrazoline at 474 nm and a 83-fold enhancement in fluorescence intensity. This probe is very sensitive and displayed a linear fluorescence off-on response to glutathione with fluorometric detection limit of 8.2 × 10(-8)M. The emission of the probe is pH independent in the physiological pH range. Live-cell imaging of HeLa cells confirmed the cell permeability of the probe and its ability to selectively discriminate GSH from Cys and Hcy in cells. The toxicity of the probe was low in cultured HeLa cells.

Novel Fe 3 O 4 magnetic nanoparticles (MNPs) modified with low toxic 3-glycidoxypropyltrimethoxysilane (GPTMS) and lysine (Lys) were synthesized. The MNPs were characterized by transmission electron microscopy, X-ray diffraction, infra-red spectra and thermogravimetric analysis. The MNPs were used to remove anionic dyes and cationic dyes, including methyl blue (MB), orange I (OR), acid red 18 (AR) and methylene blue (MEB), azure I (AZ), from aqueous solution. We investigated organic dye uptake capacity of Fe 3 O 4 @GPTMS@Lys as a function of contact time, dye concentration, and different pH. Furthermore, adsorption isotherms and kinetics were studied to understand the mechanism by which the MNPs adsorb dyes. To our delight, the improved adsorbent can not only enhance the maximum adsorption capacity for anionic dyes but also efficiently remove cationic dyes (AZ and MEB) from aqueous solution.

Cu2ZnSnS4(CZTS) thin film was successfully prepared by pulsed laser deposition using CZTS nanocrystal as a source and the thin film solar cell with the novel structure of FTO/CdS/CZTS/Mo was assembled. At the laser incident energy of 6 J·cm-2, the chemical composition of the CZTS thin film was Cu1.74Zn0.80Sn1.00S4.04,near to stoichiometric ratio. The thin film solar cell with the novel structure of FTO/CdS/CZTS/Mo gave short circuit photocurrent density of 1.01 mA·cm-2, open circuit voltage of 0.39 V, and fill factor of 0.485, corresponding to the photoelectric conversion efficiency of 0.19% at the illumination (Air Mass 1.5, 100 mW·cm-2).

Ceramidase plays an important role in regulating the metabolism of sphingolipids, such as ceramide, sphingosine (SPH), and sphingosine-1-phosphate (S1P), by controlling the hydrolysis of ceramide. Here we report the cloning and biochemical characterization of a neutral ceramidase from the red flour beetle Tribolium castaneum which is an important storage pest. The Tribolium castaneum neutral ceramidase (Tncer) is a protein of 696 amino acids. It shares a high degree of similarity in protein sequence to neutral ceramidases from various species. Tncer mRNA levels are higher in the adult stage than in pre-adult stages, and they are higher in the reproductive organs than in head, thorax, and midgut. The mature ovary has higher mRNA levels than the immature ovary. Tncer is localized to the plasma membrane. It uses various ceramides (D-erythro-C(6), C(12), C(16), C(18:1), and C(24:1)-ceramide) as substrates and has an abroad pH optimum for its in vitro activity. Tncer has an optimal temperature of 37 °C for its in vitro activity. Its activity is inhibited by Fe(2+). These results suggest that Tncer has distinct biochemical properties from neutral ceramidases from other species.

We developed a ratiometric fluorescent probe for sensing HOCl based on coumarin and rhodamine acid that is directly used as a detection moiety. The probe shows high selectivity and sensitivity toward HOCl under best working conditions of myeloperoxidase by which HOCl can be generated from hydrogen peroxide and chloride.

A new fluorescent probe, N-(4-(1,5-diphenyl-4,5-dihydro-1H-pyrazol-3-yl)phenyl)-2,4-dinitrobenzenesulfonamide (probe 3), was designed and synthesized as a highly sensitive and selective fluorescent probe for recognizing and detecting glutathione among biological thiols in aqueous media. Probe 3 is a nonfluorescent compound. On being mixed with biothiols under neutral aqueous conditions, the 2,4-dinitrobenzenesulfoyl moiety can be cleaved off by glutathione, and the blue emission of the pyrazoline at 464 nm is switched on, with a fluorescence enhancement of 488-fold for glutathione. Furthermore, probe 3 was highly selective for glutathione without interference from some biologically relevant analytes. The detection limit of glutathione was 4.11 × 10(-7) M. The emission of the probe is pH independent in the physiological pH range. Moreover, the probe can be used for fluorescent imaging of cellular glutathione and can be used for detecting glutathione in calf serum.

A series of novel 1,3,5-triarylpyrazoline derivatives was synthesized by the reaction of chalcone and 5-aryl-2-hydrazinyl-1,3,4-thiadiazole in 43.3-84.7% yields. The structures of compounds were characterized using IR, (1)H NMR and HRMS spectroscopy and X-ray diffraction analysis. The absorption and fluorescence characteristics of the compounds were investigated in dichloromethane, toluene, acetonitrile, N,N-dimethylformamide and tetrahydrofuran. The results showed that the absorption maxima of the compounds vary from 366 to 370nm depending on the group bound to benzene rings. The maximum emission spectra of the compounds in dichloromethane were dependent on nature of groups in benzene ring. Furthermore, the compound 3b can be used to determine Cu(2+) ion with high selectivity and a low detection limit in the DMF:H2O=1:1 (v/v) solution.