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Although direct acetoxylation and cyclization of alkylamide have been extensively reported, investigation of the structural influence of directing groups on selectivity is limited. Pd-catalyzed 2-methoxyiminoacyl (MIA) assisted γ-acetoxylation of alkylamides has been developed. Further DFT studies have demonstrated that the directing groups have a significant influence on the reductive elimination step. The strong electron-donating effect of the OMe group in MIA leads to the preferential formation of a five-membered cyclopalladium (OAc-Pd-C) complex, which favors the acetoxylation pathway.

We disclose herein a Au(I)-catalyzed domino cyclization of 1,6-diynes incorporated with indole. This protocol enabled the diastereoselective buildup of indole-fused azabicyclo[3.3.1]nonanes from linear precursors. Density functional theory calculations showed that the reaction proceeded via an unprecedented cascade dearomatization/rearomatization/dearomatization process. Independent gradient model analysis revealed that a noncovalent attractive interaction between the distal alkyne and the Au/proximal complex was responsible for the chemoselectivity of the first spirocyclization step.

The 2-methoxyiminoacyl-mediated arylation of substituted phenylalanines has been examined. Selective monoarylation at the ortho position was achieved using pyridone ligands which decelerate the arylation process. Density functional theory (DFT) study of a continuous C-H arylation process that included the first and second arylation stage was performed. The computational result shows that the introduction of a pyridone ligand obviously disfavors the second arylation stage, which directly contributes to the selectivity between the mono/diarylated products. Furthermore, results of the kinetic isotope effect and a control experiment are agreed with DFT study.

Electrocatalytic NO reduction controls NO emission and produces NH3 at ambient conditions. Herein, NiO nanosheet array on titanium mesh is proposed as a high-active and selective electrocatalyst for NO reduction reduction, attaining a Faradic efficiency of up to 90% with a NH3 yield of 2130 µg h−1 cm−2. Its aqueous Zn-NO battery can generate electricity with a power density of 0.88 mW cm−2 and simultaneously offer an NH3 yield of 228 µg h−1 cm−2. The NO electroreduction mechanism on NiO is revealed using theoretical calculations.

A novel 3D Eu(iii) metal-organic framework (Eu-MOF-1) formulated as [Eu(L)(H2O)(DMA)] (L = 2-(2-nitro-4-carboxylphenyl)terephthalic acid) has been successfully synthesized under solvothermal conditions and characterized by structural analyses. Eu-MOF-1 displays a new 3D framework containing EuIII ions, ligand L, and coordinated DMA molecules and water molecules. The fluorescence investigations indicate that Eu-MOF-1 emits bright red luminescence, and shows relatively high water stability and outstanding chemical stability under a relatively wide range of pH conditions. It is noteworthy that Eu-MOF-1 can quantitatively detect p-aminophenol (PAP) which is a metabolite of phenylamine in human urine. More significantly, Eu-MOF-1 is the first reported multi-responsive luminescent sensor for detecting the biomarker PAP, and MnVII and CrVI anions with high selectivity, sensitivity, recyclability and relatively low detection limits in aqueous solutions. Furthermore, the possible sensing mechanisms of Eu-MOF-1 for selective sensing have also been explored in detail. Eu-MOF-1 could be an ideal candidate as a multi-responsive luminescent sensor in biological and environmental areas.

A new copper/silver-co-mediated three-component bicyclization of benzene-linked 1,6-enynes with ICF2CO2Et with TMSN3 was reported, and used to produce a wide range of hitherto unreported difluorinated tetrahydroindeno[1,2-c]azepine-3,6-diones with moderate to good yields. The mechanistic pathway consists of radical-induced 1,6-addition–cyclization, oxidative addition, reductive elimination, nitrene insertion and N–O cleavage, resulting in continuous multiple bond-forming events including C–C and C–N bonds to build up a 6/5/7 tricyclic framework.

An aerobic oxidative cyanation for the synthesis of α-aminonitriles was reported. The formation of C(sp3)-CN bonds was achieved under a metal-free condition by utilizing azobis(isobutyronitrile) as a sole organic cyanide source with the combination of pivalic acid and sodium acetate as additives.

Background Danggui (Radix Angelicae Sinensis) is an herb often used in Traditional Chinese medicine. It is used to promote blood flow and has been used in the treatment of myocardial ischemia-reperfusion injury in animal models. Angiotensin II (Ang II) has been shown to play important roles in mediating cardiovascular diseases, and may cause cardiac hypertrophy and apoptosis. This study aimed to investigate whether Danggui has protective effects on Ang II-induced apoptosis in H9c2 cardiomyoblast cells and study the mechanisms involved. Methods We evaluated the effect of Danggui on Ang II-induced apoptosis in an in vitro model. H9c2 cardiomyoblast cells were cultured in serum-free medium for 4 hr, then treated with Danggui (50, 100 μg/ml) 1 hr pre- or post-Ang II treatment. After a further 23 hr of culture, cells were harvested for analyses with assays for apoptosis markers and cell signaling pathways. Results Our results showed that Ang II induced upregulation of pro-apoptotic Bad, instability of the mitochondria membrane potential, cytochrome c release, caspase-9 and caspase-3 activation and cardiomyocyte apoptosis. Pre- or post-treatment with Danggui reversed all of the above Ang II-induced apoptotic effects in H9c2 cells. Furthermore, the JNK (SP600125) inhibitor completely blocked Danggui inhibition of caspase-3 activation in Ang II-treated H9c2 cells. Conclusions Our results showed that Danggui either pre-treatment or post-treatment highly attenuated the Ang II-induced apoptosis in cardiomyoblast cells. The findings demonstrated that the anti-apoptosis effect of Danggui is mediated by JNK and PI3k inhibitors. Electronic supplementary material The online version of this article (doi:10.1186/1472-6882-14-358) contains supplementary material, which is available to authorized users.