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An efficiently scalable synthesis of key intermediate toward mirabegron has been developed via a mixed anhydride method, employing PivCl instead of EDCI and HOBt. The developed process produced (R)-2-hydroxy-N-(4-nitrophenethyl)-2-phenylacetamide (10) in 91.5–92.3% yield and >99.0% HPLC purity under mild conditions. During this process, a side reaction induced by triethylamine hydrochloride was discovered and investigated, which was ultimately avoided by executing the reaction in a biphasic solvent system.

A new molecular complex constructed by fumaric acid with piperazine has been prepared and characterized by single crystal X-ray diffraction. The number of fumaric acid involved in the complex equals to the number of N-protonated binding sites in the piperazine molecule. The structure contained infinite 1D supramolecular chains held together by robust, primary O–H•••O charge-assisted hydrogen bonds, and the 2D sheet like pattern constructed via the expected carboxyl-piperazine heterosynthon. Persistent N–H•••O interactions were found to play an important role in the formation of the final 3D arrays. The five dominant supramolecular synthons in the crystal structure are the heteromeric carboxylic acid•••piperazine hydrogen bond interactions, which prevail in the presence of widely differing chemical functionalities. Thermal stability of the compound has been investigated by thermogravimetric analysis (TGA) of mass loss.

Drying of lignite alters the physical and chemical structure of coal, and influences the oxygen transport on the low temperature oxidation process. This paper provides a comprehensive overview on low-temperature oxidation of lignite and its dried products, including oxygen transport during the oxidation process, changes of physical structure and chemical compositions occurring at the drying process and its effects on the oxygen transport, and restraint of dried lignite oxidation.

Gd0.6BaB9O16: Eu3+0.4 red phosphors were prepared by sol-gel technique. The different polyethylene glycols (PEGs) were added to control the particle size ofGd0.6BaB9O16: Eu3+0.4. The particle distribution and the relationship between the particle size and the luminescence properties of the phosphors were investigated. PEGs have no influence on the structure ofGd0.6BaB9O16: Eu3+0.4, but the particle size is changed with different molecular weight of PEGs. And the relative intensity of excitation peak and emission peak ofGd0.6BaB9O16: Eu3+0.4phosphor are reduced by adding PEG, due to the particle size effects.

The red phosphor Gd2(MoO4)3:Eu3+,Sm3+ was prepared by sol-gel method. The morphology and luminescence characteristics of the phosphor particles were characterized by scanning electron microscopy (SEM) and fluorophotometer. The results showed that the phosphor had the advantages of small particle size and the uniform particle size distribution. The luminescence properties of Eu3+ ions in Gd1.37Eu0.6Sm0.03(MoO4)3 could be evidently improved by co-doping of Sm3+ ions, which was due to the efficient energy transfer process from Sm3+ to Eu3+ ions. The chromaticity coordinates for Eu3+ doped Gd1.4Eu0.6(MoO4)3 and Eu3+ and Sm3+ codoped Gd1.37Eu0.6Sm0.03(MoO4)3, are(0.662, 0.329) and (0.668, 0.331), respectively. Because of the introduction of Sm3+ into the red-emitting phosphors, the chromaticity coordinates of Gd1.37Eu0.6Sm0.03(MoO4)3 phosphor is closer to the standard values of International chromaticity coordinates(0.67, 0.33). So Gd1.37Eu0.6Sm0.03(MoO4)3 shows good prospect for red phosphors of white LED.

The composition and antioxidant activities of two polysaccharides PFCAⅢ and PFCCⅠ, isolated from Fructus corni, have been investigated. The monosaccharide components of PFCAⅢ were found to be rhamnose, arabinose and glucose in a molar ratio of 13.74: 50.54: 35.72, whilst PFCCⅠ was found to consist of xylose and glucose in a molar ratio of 18.8: 81.2. The weight-average molecular weights of PFCAⅢ and PFCCⅠwere 1.74×104 and 7.57×104 respectively. The polysaccharides showed potential antioxidant activity by scavenging superoxide anion (O2−∙) and hydroxyl free radicals (OH∙) and this was confirmed by their ability to inhibit oxidation of axunge and gingili. The concentrations required to scavenge 50% of hydroxyl free radicals (EC50) of PFCAⅢ and PFCCⅠ were 430μg/ml and 80μg/ml respectively, and the extents of scavenging O2−∙ by 500μg PFCAⅢ and PFCCⅠwere 15.9% and 68.0% respectively. The polysaccharide PFCCⅠ shows much more significant antioxidant activity than PFCAⅢ. PFCCⅠ was mainly linked with β(1→4)-D-glucosyl with side chains including 1-linked β-D-Glc, 1,6-linked β-D-Glc and 1,4-linked β-D-Xyl with branching points at C-6 of 1,4-linked Glc in main chain. It had the potential to be exploited by the food and pharmaceutical industries in the future with further research on this polysaccharide.

Trust management is a distributed access control mechanism for open, large-scale network. SPKI/SDSI and RT0 are typical trust management systems. This paper compares the different crendentials in those systems essentially, and the result shows that although RT0 crendentials are relatively simple, they are expressively eauivalent to SPKI/SDSI crendentials.

R-spondin 1 (RSPO1) is a ligand for the intestinal stem cell (ISC) marker Lgr5 in the crypt, which functions to amplify canonical Wnt signaling to stimulate the division of ISCs. Despite the crucial role of recombinant human RSPO1 (rhRSPO1) in homeostasis and regeneration, little is known about RSPO1 among different species. Here, we cloned the porcine RSPO1 (pRSPO1) gene and obtained rpRSPO1 protein through the expression system of the recombinant Escherichia coliRosetta (DE3) chemical competent cells. Using the in vitro IPEC-J2 model that combines cell proliferation evaluation approaches, we identified the rpRSPO1 activity in stimulating jejunal epithelial cells. And upon deoxynivalenol challenge in mice, we found that rpRSPO1 ameliorated their growth retardation and jejunal epithelial integrity. Importantly, the ISCs in the jejunum had greater proliferation and differentiation potential that was accompanied by Wnt/β-catenin pathway activation after rpRSPO1 modulation. Subsequently, the jejunal organoids expanded from these ISCs ex vivo presented robust growth advantages. And the rpRSPO1 was able to guide Wnt/β-catenin activity to increase ISC activity. Our work systematically demonstrates that rpRSPO1 facilitates ISC expansion by potentiating Wnt/β-catenin signaling during homeostasis and responding to deoxynivalenol perturbations.