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Catalyst‐controlled switchable (4+3) and (4+2) annulation reactions of Morita–Baylis–Hillman carbonates with benzofuran‐derived azadienes have been established. Employing PCy3 as the catalyst, the reaction could provide a variety of synthetically useful benzofuro[3,2‐b]azepines in good yields (80–92%) with excellent chemo‐ and regioselectivities via (4+3) cycloaddition reactions. Whereas changing the catalyst from PCy3 to DMAP, the chemo‐ and regioselectivities were switched to construct highly substituted spirotetrahydroquinoline scaffolds with three sequential stereocenters containing all‐carbon spiro‐quaternary stereocenters in excellent efficiency and diastereoselectivities (92–96% yields with all cases>25:1 dr) via (4+2) annulations. In addition, the synthetic utility of this method was further showcased by gram‐scale reactions and synthetic transformations of the product. [ABSTRACT FROM AUTHOR]

A dearomative [4 + 2] cycloaddition of 3‐nitroindoles ortho‐amino Morita−Baylis−Hillman carbonates was established under mild conditions. This method provides an efficient and practical approach for delivering tetrahydro‐5H‐indolo[2,3‐b]quinolines containing three contiguous stereocenters, two tertiary and one quaternary, in high yield (up to 95%) with excellent diastereoselectivity (all cases >25:1 dr). The potential synthetic applications of this strategy were also highlighted by the scale‐up experiment and further synthetic transformation. Moreover, the structure and relative configuration of the cycloadduct was unequivocally confirmed by single‐crystal X‐ray diffraction. [ABSTRACT FROM AUTHOR]

A mild and effective method for the synthesis of 3‐sulfonyl‐1,2‐dihydroquinolines from N‐acyl‐protected 2‐aminobenzaldehyde with vinyl sulfones has been established. This reaction could rapidly proceed and exhibit different reactivity when employed the vinyl sulfones as nucleophile on aza‐Michael addition/cyclization reaction, allow for the production of 1,2‐DHQs in high yields up to 95%. In addition, the chemical structure of the product was confirmed by x‐ray single‐crystal structure analysis. [ABSTRACT FROM AUTHOR]

Electron‐withdrawing groups (EWG) have emerged as a powerful tool for the activation of various arenes to promote nucleophilic dearomative additions for the construction of complicated chiral cyclic structures under asymmetric catalytic systems. Nitro‐indoles, nitro‐benzofurans/benzothiophenes, and related nitro‐heteroarenes are widely applied in the reaction with various nucleophiles to construct various enantioenriched polycyclic skeletons via the asymmetric dearomatization process. Meanwhile, the electron‐deficient azo‐group and nitroso‐group are an alternative powerful tool for the activation of arenes, which enable formal nucleophilic aromatic arylations with various electrophilic aromatics to construct novel chiral biaryl atropisomers. Besides, azo‐naphthanenes are served as dipolar surrogates in the reaction with nucleophilic dipolarophiles to proceed asymmetric cycloadditions to construct chiral polycyclic skeletons. The EWG‐tethered arene has proven to be a versatile protocol for the construction of structurally diversified chiral backbones. This review summarizes the latest progress of the EWG‐tethered arenes involved asymmetric transformations under organo‐ or transition metal catalysis. [ABSTRACT FROM AUTHOR]

A general approach to substituted pyrrolidines via [3 + 2] cycloaddition between nonstabilized azomethine ylides and cyanosulfones was developed. The efficient method provides a series of substituted pyrrolidines bearing a quaternary carbon center in high yields (up to 98%) excellent diastereoselectivities (up to >25:1 dr) under ambient reaction conditions. [ABSTRACT FROM AUTHOR]

The additive‐free 1,3‐dipolar cycloaddition reaction of isatin‐derived azomethine ylides with α‐cyano‐α,β‐unsaturated compounds was developed, which enabled diversity‐oriented synthesis of a series of novel and structurally complex 3,3′‐pyrrolidinyl‐spirooxindoles derivatives containing four contiguous and two quaternary stereogenic centers in high yields (up to 92%) and excellent diastereoselectivities (up to >25:1 dr). The reaction displays switchable regioselectivity depending on the steric effect of the substrates. [ABSTRACT FROM AUTHOR]

Intraplantar injection of formalin produces persistent spontaneous nociception and hyperalgesia. The underlying mechanism, however, remains unclear. The present study was, therefore, designed to determine the roles of peripheral group III metabotropic glutamate receptors (mGluRs) in formalin‐evoked spontaneous nociception. Pre‐treatment with intraplantar injections of L‐serine‐O‐phosphate (L‐SOP), a group III mGluRs agonist, significantly inhibited formalin‐induced nociceptive behaviours and decreased Fos production in the spinal dorsal horn. The inhibitory effects of L‐SOP were abolished completely by pre‐treatment with the group III mGluR antagonist (RS)‐a‐methylserine‐O‐phosphate (M‐SOP). These data suggest that the activation of group III mGluRs in the periphery may play a differential role in formalin‐induced nociception. In addition, L‐SOP decreased the formalin‐induced upregulation of tumour necrosis factor‐α (TNF‐α) as well as interleukine‐1β (IL‐1β) expression in the spinal cord, suggesting that activation of peripheral group III mGluRs reduces formalin‐induced nociception through inhibition of the pro‐inflammatory cytokines in the spinal cord. Therefore, the agonists acting peripheral group III mGluRs possess therapeutic effectiveness in chronic pain. [ABSTRACT FROM AUTHOR]

A simple and efficient method for the synthesis of tricyclic imidazolines derivatives via [3 + 2] 1,3‐dipolar cycloaddition between nonstabilized azomethine ylide generated in situ with unactivated cyclic imines is reported here. The method provided easy and mild access to various fused tricyclic hexahydroimidazo[5,1‐a]isoquinolines in excellent yields (up to 96%). This protocol is simple and easy to handle. [ABSTRACT FROM AUTHOR]

A rapid and highly efficient 1,3‐dipolar [3 + 2] cycloaddition of nonstabilized azomethine ylides generated in situ with benzo[b]thiophene 1,1‐dioxides as the dipolarophiles has been developed. The efficient method affords tricyclic pyrrolidine‐fused benzo[b]thiophene 1,1‐dioxide derivatives in high to excellent yields (up to 99%) with excellent diastereoselectivities (up to >25:1 dr) under mild reaction conditions. The structure of a typical product was confirmed by X‐ray crystallography. [ABSTRACT FROM AUTHOR]

In this paper, multicomponent silicone hydrogels were prepared by the copolymerization of the hydrophobic silicon-containing monomer bis(trimethylsilyloxy) methylsilylpropyl glycerol methacrylate with two hydrophilic monomers 2-hydroxyethyl methacrylate and N-vinyl pyrrolidone. The response of the silicone hydrogels to different stimuli was evaluated by observing the swelling ratios of the hydrogels. The results show that the hydrogels display different responses to variations in pH and solvent. Multifunctional sensors were then prepared based on the silicone hydrogels to detect the pH value of solutions, the types of solvent and the ethanol percentage in water. The results could be obtained by visual inspection and the sensors were reusable. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Models of crop residue reflectance under changing moisture conditions are required to better quantify management of crop residue in agricultural fields by remote sensing. In this study, reflectance spectra (400-2400 nm) of four different crop residues were measured in the laboratory under various moisture conditions. Crop residue reflectance decreased with increasing water content across all wavelengths, especially in the shortwave infrared (SWIR) region. For each crop residue, both linear and exponential models were capable of quantifying the relationship between reflectance and mass water content (M WC) with high accuracy [e.g., coefficient of determination (R-) > 0.9 and root mean square error (RMSE) < 0.025 at each wavelength in the SWIR]. The best-fitting parameters of the two models could be directly derived from the reflectance of dry and saturated crop residues and saturated water content, which simplified the construction of the models. The results of regression analyses between the predicted M WC calculated by the inversion of the two models and measured M WC indicated that M WC could be estimated with high accuracy (R² > 0.9, RMSE <0.15, slope close to 1.0, and intercept close to 0.0) at nearly every wavelength in the SWIR. To construct a general model, the reflectance was normalized, and the results suggested that this method was valid. The results of this study help to quantify the effect of water on the spectral reflectance of crop residue and should contribute to better correct the effects of water on remote sensing estimation of crop residue cover in the future. [ABSTRACT FROM AUTHOR]

The Schools of Nursing of Tianjin Medical College and the University of Ottawa have been partners in a Canadian-Chinese linkage project funded by the Canadian International Development Agency (CIDA) and the Chinese Government since 1989, at the instigation of Canadian faculty member Nancy Johnson who saw the need for academic support for the Chinese nursing community.

In the crystal structure of the title compound, [Co(C5H5)(C13H10)], the Co atom is connected to two five-membered rings. Both rings are disordered and were refined using a split model. [ABSTRACT FROM AUTHOR]

In the crystal structure of the title compound, [AuCl{Co(C5H5)(C5H4P tBu2)}]PF6 or [AuCo(C5H5)(C13H22P)Cl]PF6, hexa­fluoro­phosphate is an uncoordinated anion. The structure contains η5-(C5H5)C—H⋯F hydrogen bonds. [ABSTRACT FROM AUTHOR]