Dehydrogenative Silylation of Alkenes for the Synthesis of Substituted Allylsilanes by Photoredox,Hydrogen‐Atom Transfer,and Cobalt Catalysis

A synergistic catalytic method combining photoredox catalysis, hydrogen‐atom transfer, and proton‐reduction catalysis for the dehydrogenative silylation of alkenes was developed. With this approach, a highly concise route to substituted allylsilanes has been achieved under very mild reaction conditions without using oxidants. This transformation features good to excellent yields, operational simplicity, and high atom economy. Based on control experiments, a possible reaction mechanism is proposed.     

Synthesis and Antitumor Evaluation of Novel Hybrids of Phenylsulfonylfuroxan and Estradiol Derivatives

Fifteen novel furoxan-based nitric oxide (NO) releasing hybrids of estradiol derivatives were synthesized and evaluated in vitro anti-proliferative activity in MDA-MB-231, A2780, Hela and HUVEC cell lines. Most of them displayed potent anti-proliferative effects. Among the compounds, 4-bromo-3-((phenylsulfonyl)-1,2,5-oxadiazole 2-oxide)-oxy-propoxy-estradiol ( 11 b ) exhibited the best activity with IC₅₀ values of 3.58–0.0008 μM. Preliminary pharmacological studies showed that 11 b induced apoptosis and hardly affected the cell cycle of MDA-MB-231 cell line. NO-releasing capacity and inhibition of ERK/MAPK pathway signaling might explain the potent antineoplastic activity of these compounds. The preliminary structure-activity relationship (SAR) showed that steroidal scaffolds with a linker in 3-position were favorable moieties to evidently increase the bioactivities of these hybrids. Overall, these results implied that 11 b merited to be further investigated as a promising anti-cancer candidate.     

Friedel-Crafts alkylation of indoles with nitroalkenes catalyzed by Cu(Ⅱ)-imine complex

A series of new ligands L₁-L₇ were readily prepared in one step.Friedel-Crafts alkylation of indoles with nitroalkenes catalyzed by a novel Cu（Ⅱ）-L complex has been developed.The remarkable advantages of this reaction are mild reaction conditions,simple workup procedure,high yields of products and the use of ethanol as a green solvent.     

Direct synthesis of 3,5-diaryl-1,2,4-oxadiazoles using 1-(2-oxo-2-arylethyl)pyridin-1-iums with benzamidines

An efficient domino protocol for the synthesis of 1,2,4-oxadiazole derivatives from readily available 1-(2-oxo-2-arylethyl)pyridin-1-iums and amidine hydrochlorides was developed. In this practical approach, N-acyl amidine precursors were formed firstly via a simple nucleophilic substitution, without the purification of N-acylamidine intermediates, and the following intramolecularly dehydrative cyclization gave 1,2,4-oxadiazole derivatives in the presence of I₂/K₂CO₃/DMSO, which exhibited excellent functional group tolerance and proceeded under simple experimental conditions.     

A New Compound—Nanoline K2Ti8O15

In the product of carbon made from tar oil by plasma pyrogenation, some nanowires, whose diameter is 9~20 nm and whose length is 300 nm were found. The result of X-ray Energy Dispersed Spectrum (EDS) indicated that it is a new compound K2Ti8O15, which has never been reported before. Compared with the corresponding stoichiometry compound K2Ti8O15, it is a non-stoichiometry compound in which two oxygen atoms are absent. It is due to the fact that the intensive deoxidization occured in the experimental process and the valence of titalium is alterable. Its microstructure in detail by high revolution electromicroscopy (HREM) and X-ray diffraction were studied.     

磷钼酸和磷钼钒酸及其盐的氧化还原特性

本文以硫酸为支持电解质,在水-1,4-二氧六环混合溶剂中,用电化学方法研究了Keggin结构的H₃PMo₁₂O₄₀、M₃PMo₁₂O₄₀(M=NH₄,Na,K)、H₄PMo₁₁VO₄₀及M_nH_4-nPMo₁₁VO₄₀(M=Na,La,K,Eu;对于Na和La,n=1～4,对于K,n=4;对于Eu,n=2)的氧化还原特性。还分析了钼和钒的氧化还原顺序及其可逆性。     

Anionic Conduction in Blends of Poly(Pyridinium Ethyl Methacrylate Perchloride) and Poly[Oligo(Oxyethylene) Methacrylate-Co-Acrylamide]

Abstract

Blends of poly(pyridinium ethyl methacrylate perchloride) and poly[oligo(oxyethylene) methacrylate-co-acrylamide] were prepared, and the ionic conductivity and mobility of the blends were investigated. Results indicate that both the transference of perchlorate anion and the dissociation of the polymeric salt in the comblike polyether obey the thermoactivation mechanism, and that the perchlorate anion in the blends is free.     

Synthesis and properties of novel stilbene-twelve alkyl quaternary ammonium salts as antibacterial optical whitening agents

Four novel stilbene-twelve alkyl quaternary ammonium salts 5a–d were synthesized. All synthesized compounds were characterized by FT-IR, ¹H-NMR and elemental analysis. Compounds 5a–d showed efficient whitening effect on cotton fiber and high fastness. Furthermore, compound 5c showed better stability to light than C186 in aqueous solution. The preliminary biological experiment demonstrated compounds 5a–d possessed significant antibacterial activities. Among them, compound 5d turned out to be the most active compound against Candida albicans with MIC₅₀ 4 μg/mL as well as E. coli with MIC₅₀ 16 μg/mL.     

Excited state intramolecular redox reaction of 2-(hydroxymethyl)anthraquinone in aqueous solution

The title compound undergoes a novel excited state intramolecular redox reaction in which the 'distal' side chain benzylic alcohol is oxidized to the aldehyde and the carbonyl moieties of anthraquinone reduced, with evidence suggesting that the primary photochemical process is a deprotonation of the benzylic C-H proton (by water) mediated by the solvent.