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Tetrasubstituted imidazoles were synthesized in high yields via the four-component reaction of aromatic aldehydes, amines, substituted benzils and ammonium acetate catalyzed by a porous CeO nanorod. Their anti-cancer activities on the Huh-7 hepatocellular carcinoma cell and antibacterial activities on four bacterial species (wild-type Escherichia coli, wild-type Staphylococcus aureus, Pseudomonas aeruginosa PAM1032 and Escherichia coli-NMD-1) in vitro were evaluated. One compound ( 5p) was screened out because of its high inhibition rate on all four bacterials at 100 μg/mL. Three products ( 5p, 5t and 5y) showed a high inhibition rate on the Huh-7 hepatocellular carcinoma cell at 10 μg/mL. The results indicated their potential in new drug development. [ABSTRACT FROM AUTHOR]

A new fluorescent sensor based on a benzimidazole unit bearing bis(ethoxycarbonylmethyl)amino groups was designed and synthesized. The ligand exhibits strong sensitivity and selectivity for Ag+ by enhanced fluorescent intensity in the presence of a wide range of other tested metal ions in methanol. The colorimetric and fluorescent response to Ag+ can be conveniently detected even by the naked eye, which offers a facile method for visual detection of Ag+. [ABSTRACT FROM AUTHOR]

A total of 20 new indole analogs were synthesized and evaluated for biological activity against Sclerotinia sclerotiorum, Altenaria solani, Verticillium dahliae, Fusarium oxysporum, Pythium walnuts, and Curvularia zea. The preliminary biological testing showed that most of the synthesized compounds exhibited fungicidal activities. Notably, compounds 2 and 7 showed the broadest and most effective activities among the compounds tested and could be potential new lead compounds for the future development of antifungal agents. [ABSTRACT FROM AUTHOR]

A novel fluorescent chemosensor containing 1 H -phenanthro[9,10- d ]imidazole moieties linked to double ethylenediamino units was synthesized. It exhibits high sensitivity and selectivity in aqueous media for Ag + with obvious change in color and 12.55-fold fluorescence quenching. The detection limit was calculated as 1.01 × 10 −7 M by a fluorescence titration experiment. The 1:1 binding stoichiometry of L –Ag + complex was analyzed by Job’s plot and further confirmed by ESI-MS. Furthermore, the recognition pattern was suggested through the FTIR and 1 H NMR spectroscopy. [ABSTRACT FROM AUTHOR]

To achieve an efficient visible-light absorption and degradation of bismuth vanadate (BiVO), in this paper, a carbon-doped (C-doped) nanosheets monoclinic BiVO (m-BiVO), with thicknesses within 19.86 ± 8.48 nm, was synthesized using polyvinylpyrrolidone K-30 (PVP) as a template and l-carbonic as the carbon source by one-step hydrothermal synthesis method. This C-doped BiVO in three-dimensional (3D) hierarchical structure enjoys high visible-light photocatalytic property. The samples were characterized using x-ray diffraction, scanning electron microscope, Raman spectra, energy dispersive spectrometer, transmission electron microscope, x-ray photoelectron spectroscopy, UV-Vis diffused reflectance spectroscopy, specific surface area, electron spin resonance, and transient photocurrent response, photoluminescence spectra, and incident-photon-to-current conversion efficiency, respectively. What is more, we studied the C-doping effect on the band-gap energy of BiVO based on First-principles. X-ray diffraction analysis showed that all photocatalysts were in the same single monoclinic scheelite structure. According to the other characterization results, the element C was successfully doped in BiVO, resulting in the 3D hierarchical structure of C-doped BiVO (P-L-BiVO). We speculated that it could be the directional coalescence mechanism by which the l-cysteine promoted the two-dimensional growth and C-doping process of BiVO, thus leading to the formation of nanosheets which were then promoted into 3D self-assembly by PVP and the shortening of the band gap. Among all samples, P-L-BiVO can make the highest removal ratio of rhodamine B under visible-light irradiation. The stability of P-L-BiVO was verified by recycle experiments. It showed that P-L-BiVO had strong visible-light absorption behavior and high electron-hole separation efficiency and stability, making a significant advantage in actual situation. [ABSTRACT FROM AUTHOR]

In order to realize high efficiency visible-light absorption and electron–hole separation of bismuth vanadate (BVO), we synthesized carbon-doped BVO (C-BVO) with high visible-light absorption behavior. We used polyvinylpyrrolidone K-30 as a template and l-cysteine as the carbon source in a one-step hydrothermal synthesis method, and then obtained the carbon-doped BVO@multi-walled carbon nanotubes (C-BVO@MWCNT) by a two-step method. The carbon nanotubes were characterized by X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy, UV-vis diffuse reflectance spectroscopy, specific surface area, electron spin resonance, and transient photocurrent responses. The XRD analysis confirmed that all photocatalysts were in the same crystal form with a single monoclinic scheelite structure. Combining this with the other characterization results, we showed that the carbon element was successfully doped in BVO and the resulting C-BVO was successfully coupled with multi-walled carbon nanotubes. The removal ratio of rhodamine B by C-BVO@MWCNT was much higher than those by BVO and C-BVO under visible-light irradiation. Recycling experiments verified the stability of C-BVO@MWCNT, which was proved to offer excellent adsorption, strong visible-light absorption behavior, and high electron–hole separation efficiency. Such properties are expected to be useful in practical applications. [ABSTRACT FROM AUTHOR]

Abstract: Novel visible-light-driven Sb2O3/WO3 photocatalysts were prepared by a hydrothermal synthesis followed by heat treatment, and characterized by transmission electron microscopy (TEM), scanning electron microscope (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), BET surface area, Fourier transform infrared spectroscopy (FT-IR) and photoluminescence spectra (PL). The photocatalytic activities of Sb2O3/WO3 photocatalysts were evaluated by the rhodamine B degradation using a LED lamp as visible light irradiation. Compared with pure WO3 and Sb2O3, the significantly enhanced photocatalytic activities of the Sb2O3/WO3 composite particles are attributed to the decrease of the recombination rate of photoinduced electron–hole pairs due to the coupling of Sb2O3 and WO3 within the composite nanoparticles. Studies of Sb2O3/WO3 composites indicate that one approach to design composite materials with enhanced photocatalytic performance is through coupling Sb2O3 with WO3, which the lowest energy states for electrons and holes are in different semiconductors. [Copyright &y& Elsevier]