An unprecedented palladium-catalyzed cyanation of aromatic C-H bonds by using tertiary amine derived isocyanide as a novel cyano source was developed. Cu(TFA)(2) was used as a requisite stoichiometric oxidant. Mechanistic studies suggest that a tertiary carbon cation-based intermediate is involved following the C-N bond breakage.

SummaryHeparanase, a heparan sulfate (HS)-specific endoglycosidase, plays an important role in inflammation and mediates acute pulmonary and renal injuries during sepsis. To explore its role in septic intestinal injury, a non-anticoagulant heparanase inhibitor, N-desulfated/re-N-acetylated heparin (NAH), was administrated to a mouse sepsis model induced by cecal ligation and puncture (CLP). Immunohistochemical staining revealed massive shedding of HS from the intestinal mucosal surfaces after CLP, and effective inhibition of heparanase by NAH was confirmed by markedly reduced HS shedding. Following CLP, intestinal expression of heparanase was increased, whereas pretreatment with NAH reduced the sepsisinduced upregulation of heparanase expression. Meanwhile, CLP led to shedding of syndecan-1 and upregulated expression of proteases such as matrix metalloprotease-9 and urokinase-type plasminogen activator in the intestine, whereas NAH markedly suppressed syndecan-1 shedding and protease upregulation following CLP. In addition, pretreatment with NAH attenuated intestinal injury, inhibited neutrophil infiltration and suppressed the production of inflammatory cytokines (tumor necrosis factor-α, interleukin-1β, and interleukin-6) in the intestine during sepsis, and it also significantly reduced the elevation of inflammatory cytokines in the serum 24 hr after CLP. Our findings demonstrate that the activation of intestinal heparanase contributes to intestinal injury during early sepsis by facilitating the destruction of mucosal epithelial glycocalyx and promoting inflammatory responses. (J Histochem Cytochem 65:241-249, 2017)

A selective C3 carboxamidation of indoles including free (N-H) ones by palladium-catalyzed sequential C-H activation-isocyanide insertion has been developed.

An efficient synthesis of free (NH)-phenanthridinones through Pd-catalyzed C(sp(2))-H aminocarbonylation of unprotected o-arylanilines under an atmospheric pressure of CO has been developed. Some ortho heteroarene substituted anilines as well as N-alkyl protected o-arylanilines are also suitable substrates for this C-H aminocarbonylation reaction.

A base-controlled synthesis of 2-substituted secondary and tertiary 1H-indole-3-carboxamides through PdCl(2)-catalyzed cyclization of o-alkynyltrifluoroacetanilides followed by isocyanide insertion has been developed. The reaction proceeds smoothly at ambient temperature using O(2) in air as the sole oxidant of the palladium catalyst.

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We identified and cloned the two precursors of miR158 and its target gene in Brassica campestris ssp. chinensis, which both had high relative expression in the inflorescences. Further study revealed that over-expression of miR158 caused reduced pollen varbility, which was caused by the degradation of pollen contents from the binucleate microspore stage. These results first suggest the role of miR158 in pollen development of Brassica campestris ssp. chinensis. MicroRNAs (miRNAs) play crucial roles in many important growth and development processes both in plants and animals by regulating the expression of their target genes via mRNA cleavage or translational repression. In this study, miR158, a Brassicaceae specific miRNA, was functionally characterized with regard to its role in pollen development of non-heading Chinese cabbage (Brassica campestris ssp. chinensis). Two family members of miR158 in B. campestris, namely bra-miR158a1 and bra-miR158a2, and their target gene bra027656, which encodes a pentatricopeptide repeat (PPR) containing protein, were identified. Then, qRT-PCR analysis and GUS-reporter system revealed that both bra-miR158 and its target gene had relatively high expression levels in the inflorescences. Further study revealed that over-expression of miR158 caused reduced pollen varbility and pollen germination ratio, and the degradation of pollen contents from the binucleate microspore stage was also found in those deformed pollen grains, which led to pollen shrinking and collapse in later pollen development stage. These results first shed light on the importance of miR158 in pollen development of Brassica campestris ssp. chinensis.

A three-component reaction involving isocyanides, o-alkynyltrifluoroacetanilides, and amines for the efficient synthesis of 2-substituted 1H-indole-3-carboxamidines has been developed. The reaction proceeds through intramolecular aminopalladation of alkynes activated by isocyanide-ligated palladium(II) species. Dioxygen acts as the sole oxidant to regenerate the active palladium(II) species.