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The functionalization of indoles in the carbocyclic ring has been achieved via organocatalytic enantioselective Friedel–Crafts benzhydrylation of hydroxyindoles with in situ generated ortho-quinome...

A fast and highly enantioselective chlorination of 4-pyrazolones catalyzed by bis(oxazoline)–Cu(ClO4)2·6H2O complexes has been developed. Under the optimized conditions, a series of pyrazolones bearing stereogenic chlorine-attached carbon centers were obtained in moderate to high yields (up to 98%) and with enantioselectivities of up to 98% ee.

A chiral amine squaramide catalyzed the conjugated addition of pyrazolin-5-ones to in situ generated ortho-quinomethanes (o-QMs) was developed to construct 4-tetrasubstituted pyrazolin-5-ones featuring adjacent quaternary and tertiary stereocenters in oil–water phases. High yields, excellent stereoselectivities, mild conditions and accessible scale-up demonstrated the fascination of this reaction protocol.

A highly regioselective and enantioselective N-alkylation of isoxazol-5-ones with para-quinone methides promoted by bi-functional squaramide catalysts was developed. This unexpected asymmetric N-addition of isoxazolinones afforded a series of enantioenriched N-diarylmethane substituted isoxazolinones with high yields and enantioselectivities (up to 97 : 3 er). This reaction not only provides a useful approach for intermolecular chiral C–N bond formation but also demonstrates the immense potential of isoxazol-5-ones as N-nucleophiles in catalytic asymmetric reactions.

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BACKGROUND It is well known that nonalcoholic fatty liver disease (NAFLD) is associated with insulin resistance (IR). LB100, a serine/threonine protein phosphatase 2A (PP2A) inhibitor, is closely related to IR. However, there is little data regarding its direct influence on NAFLD. AIM To elucidate the effect and underlying mechanism of LB100 in NAFLD. METHODS After 10 wk of high fat diet (HFD) feeding, male C57BL/6 mice were injected intraperitoneally with vehicle or LB100 for an additional 6 wk (three times a week). The L02 cell line was treated with LB100 and free fatty acids (FFAs) for 24 h. Hematoxylin and eosin and oil red O staining were performed for histological examination. Western blot analysis was used to detect the protein expression of Sirtuin 1 (Sirt1), total and phosphorylated AMP-activated protein kinase α (AMPKα), and the proteins involved in lipogenesis and fatty acid oxidation. The mRNA levels were determined by qPCR. Pharmacological inhibition of AMPK was performed to further examine the exact mechanism of LB100 in NAFLD. RESULTS LB100 significantly ameliorated HFD-induced obesity, hepatic lipid accumulation and hepatic injury in mice. In addition, LB100 significantly downregulated the protein levels of acetyl-CoA carboxylase, sterol regulatory element-binding protein 1 and its lipogenesis target genes, including stearoyl-CoA desaturase-1 and fatty acid synthase, and upregulated the levels of proteins involved in fatty acid β-oxidation, such as peroxisome proliferator-activated receptor α (PPARα), peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α), carnitine palmitoyltransferase 1α, acyl-CoA oxidase 1 and uncoupling protein 2, as well as the upstream mediators Sirt1 and AMPKα in the livers of HFD-fed mice. In vitro, LB100 alleviated FFA-induced lipid accumulation in L02 cells through the AMPK/Sirt1 signaling pathway. Further studies showed that the curative effect of LB100 on lipid accumulation was abolished by inhibiting AMPKα in L02 cells. CONCLUSION PP2A inhibition by LB100 significantly ameliorates hepatic steatosis by regulating hepatic lipogenesis and fatty acid oxidation via the AMPK/Sirt1 pathway. LB100 may be a potential therapeutic agent for NAFLD.

Enhancement of the interfacial structure has great significances in achieving polymer blends with high mechanical performance. To improve the mechanical properties of poly( l -lactide) (PLLA)/poly(propylidene carbonate) (PPC) blends, the covalent functionalized graphene oxide by PLLA chains (PLLA-g-GO) was synthesized by a two-step strategy. It could migrate from the thermally preferred PPC phase to the interfaces of PLLA and PPC and promote the formation of a network-like structure. As a consequence, the tensile strength and elongation at break were both improved. Furthermore, the PLLA-g-GO located at the interface could induce the crystallization at the boundary, which brought the significant improvement of the tensile strength and elongation at break. This result may be beneficial for designing high-performance PLLA materials.

Fully biodegradable blends with low shape memory recovery temperature were obtained based on poly(lactic acid) (PLA) and poly(propylene carbonate) (PPC). By virtue of their similar chemical structures, in situ cross-linking reaction initiated by dicumyl peroxide (DCP) between PLA and PPC chains was realized in PLA/PPC blends. Therefore, the compatibility between PLA and PPC was increased, which obviously changed the phase structures and increased the elongation at break of the blends. The compatibilized blends had a recovery performance at 45 °C. Combining the changes of phase structures, the mechanism of the shape memory was discussed. It was demonstrated that in situ compatibilization by dicumyl peroxide was effective to obtain eco-friendly PLA/PPC blends with good mechanical and shape memory properties.

To validate the HJ-1A HSI red edge indices, spectral reflectance data from EO-1 Hyperion of close date were used to simulate the band reflectance of HJ-1A HSI. Four red edge indices (red vale position, red edge position, red edge slop and red edge swing) were extracted from both simulated and actual HJ-1A HSI band reflectance. Comparisons of the 4 red edge indices between simulated and actual HJ-1A HSI were made to validate the red edge indices product of HJ-1A HSI. The average correlation coefficient of red edge reflectance between actual and simulated HJ-1A HSI is 0.946 and its standard deviation is 0.011, thus a high consistency could be found. The correlation coefficients of red edge indices between simulated and actual HJ-1A HSI were 0.414, 0.543, 0.808 and 0.802 for red edge position, red vale position, the red edge swing and red edge slop respectively. An obvious regular varying trend was found for these 4 red edge indices along different vegetation cover fraction. The standard deviations of differential images between real and simulated HJ-1A HSI red edge indices are 5.75, 1.86, 5.7 e(-4) and 0.024. The result showed that the red edge indices from HJ-1A HSI is consistent with that from simulated indices from Hyperion; the vegetation variation could be effectively reflected in HJ-1A HSI red edge indices.