In Situ Hypoiodite-Catalyzed Oxidative Rearrangement of Chalcones: Scope and Mechanistic Investigation.

It is highly desirable to avoid using rare or toxic metals for oxidative reactions in the synthesis of pharmaceuticals and fine chemicals. Hypervalent iodine compounds are environmentally benign alternatives, but their catalytic use has been quite limited. Herein, the protocol for in situ hypoiodite-catalyzed oxidative rearrangement of chalcones is first realized under mild and metal-free conditions, which provided a nontoxic, environmental-benign, and catalytic alternative to the thallium-based protocol. Also, the applicability and effectiveness of this catalytic protocol got well demonstrated via gram-scale synthesis and product derivatization. What is more, control and NMR tracking experiments were performed to figure out the possible catalytic species and intermediates.

[Study of biological characteristics of the IVpi-189 virus derived from persistent influenza A virus-infected cell line].

To investigate biological characteristics of the IVpi-189 progeny virus derived from the culture of influenza A virus as a live-attenuated vaccine candidate. Persistent infection of a cultured cell line with influenza A virus (MDCK-IVpi) was established by incubating continuously influenza virus-infected cells at a lower temperature. The infectious progeny virus derived from MDCK-IVpi cells at the 189rd subculture was designated as the IVpi-189 strain of influenza virus. The cytopathic effect induced by IVpi-189 virus was observed under different temperature conditions. The production of infectious progeny virus was examined at 38 and 32 degrees C by plaque titration of cell-associated and released virus. IVpi-189 virus showed cytopathic effect as strong as that of IVwt in infected cell line of MDCK at 32 degrees C. However, when culture temperature was raised to 38 degrees C, the cytopathic effect induced by IVpi-189 virus was delayed and less pronounced. Virus growth in IVpi-189 virus-infected cells at 38 degrees C was significantly reduced as compared with that of IVwt virus, although both viruses yielded nearly equivalent high titers of cell-associated and released virus at 32 degrees C. The reasons of the decreased proliferative ability of IVpi-189 virus at high culture temperature were unrelated with virus inactivation or the release of progeny virus, but associated with the decreased replication of infectious progeny virus in the infected cells. IVpi-189 virus derived from MDCK cells infected persistently with influenza A virus showed biological characteristics as a potential live-attenuated vaccine candidate.

[Effect of heat treatment on the electrocatalytic activity of SnO2/Ti anode in degradation of p-benzoquinone].

Sb-doped SnO2/Ti anode was prepared in our lab with thermal decomposition method, and in the same time, the effect of heat treatment on the properties of the electrode also was studied. Scanning electron microscopy (SEM) was used to study the surface characterization of the electrodes. X-ray photoelectro-spectroscopy (XPS) measurements were carried out to study the chemical state of elements, Sn and Sb. The potentiodynamic polarization behaviors of the two anodes in different solutions were performed. Galvanostatic electrolyses were carried out at 5 mA/cm2 to study the electrocatalytic activity of the two anodes in removing organic pollutant. SEM showed that the electrodes had the same well-known cracked-mud structure, while the electrode annealed in O2 [SnO2/Ti(O2)] had more larger surface area than the electrode annealed in the air [SnO2/Ti(air)]. XPS measurements showed that the binding energies of both Sn3d(5/2) and Sb3d(5/2) of SnO2/Ti(O2) were 0.15 eV smaller than what of the SnO2/Ti(air) film. Both of the electrochemical measurements and electrolyses results confirmed that SnO2/Ti(O2) was more active in the degradation of organic pollutant. The galvanostatic electrolyses lasted until the solutions were decoloured throughly, 76.3% of total organic carbon (TOC) was removed with SnO2/Ti(O2), compared with 63.3% of SnO2/Ti(air). The similar exponential rules were driven for the variations of residual TOC concentration with two anodes.