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Ethnopharmacological relevance: Astragalus polysaccharide (APS), the most biologically active ingredient of Astragali Radix, is used to treat diabetes mellitus (DM)-related chronic wounds in traditional Chinese medicine for several decades. This herb possesses an anti-inflammatory effect. Our study proved that APS can reduce excessive inflammation at the late phase of wound-healing in diabetic ulcers. Aim of the study: To clarify the molecular mechanism of APS in promoting wound-healing via reducing excessive inflammation in diabetic ulcers during the late stages of wound-healing. Methods and materials: The rat model of the diabetic ulcers was established via intraperitoneal injection of streptozocin (60 mg/kg). We detected the regulation of APS on diabetic ulcers by measuring wound-healing rates. Bioinformatics was used to predict the target genes of APS, and autodocking was used to predict the combination of APS and target genes. Immunohistochemistry, Enzyme-linked immunosorbent assay, Western blot, immunofluorescence staining, flow cytometry, and flow cytometric sorting were investigated. Results: The results demonstrated that APS promoted wound-healing and inhibited excessive inflammation at the late phase of wound-healing in diabetic rats. Mechanistic findings showed that APS promoted the expression of β-catenin and Rspo3 while inhibiting the expression of NF-KB and GSK-3β, which leads to the transformation of M1-type macrophages into M2-type macrophages and thus reducing excessive inflammation at the late phase of wound-healing in diabetic ulcers. Conclusion: We found an interesting finding that APS promoted the polarization of macrophages towards M2-type through the β-catenin/NF-κB axis to reduce excessive inflammation at the late phase of wound-healing. Therefore, APS may be a promising drug for treating diabetic ulcers in clinic.

The influences of basalt fibre on morphology, mechanical properties, structure, contact angle, melting and crystallization behaviours of polyamide 1012 were studied using scanning electron microscopy, material testing machine, X-ray diffractometer, differential scanning calorimeters and static contact angle measuring instrument. It was found that interface properties between basalt fibre and polyamide 1012 were improved effectively by silane coupling agent. Also, the tensile and flexural strength of treated basalt fibre-reinforced composites were found to be higher than untreated ones at the same fibre content. The best tensile and flexural strength of polyamide 1012/treated basalt fibre composites with 30 wt% basalt fibre were determined to be 84.4 and 120 MPa. Although basalt fibre did not change polyamide 1012 crystal structure, it altered the melting temperature and degree of crystallinity of polyamide 1012. In addition, by virtue of the changes in crystallization temperature, the nucleation ability of polyamide 1012 in composites was confirmed to be enhanced. The strong interaction between epoxy groups of silane coupling agent and amide groups of polyamide 1012 elevates the hydrophobic properties of composites. The results from nonisothermal crystallization kinetics testified that crystallization ability of polyamide 1012 in composite containing 30 wt% basalt fibre was strengthened, compared with neat polyamide 1012. [ABSTRACT FROM AUTHOR]

Visible light-enhanced [3 + 2] cycloaddition of N , N -disubstituted hydrazines with N -cyano- N -aryl- p -toluenesulfonamides is an efficient reaction pathway to polysubstituted 1,2,4-triazol-3-amines. The reaction is performed under mild conditions without the addition of any transition metals. This strategy involves a C(sp 3 )-H bond activation, a cyano cycloaddition, and the formation of two new C═N bonds. The protocol shows the advantages of good functional group tolerance and broad substrate scope. The late-stage modification experiments provide practical applications in the field of organic synthesis and medicinal chemistry.

A facile and efficient catalyst-/metal-/oxidant-free DBU-promoted deaminative thiolation reaction of 1 H -benzo[ d ]imidazol-2-amines and benzo[ d ]oxazol-2-amines has been developed at room temperature conditions in a one-pot protocol. This practical three-component strategy represents a novel and environmentally friendly reaction pathway toward the straightforward synthesis of various 2-thio-1 H -benzo[ d ]imidazoles and 2-thiobenzo[ d ]oxazoles using carbon disulfide as a sulfur source through C-N bond cleavage and C-S bond formation process. Different types of 1 H -benzo[ d ]imidazol-2-amines, benzo[ d ]oxazol-2-amines, and organic bromides are suitable substrates. The gram-scale and late-stage modification experiments provide the potential applications based on this methodology in the field of organic and medicinal chemistry.

A facile access to benzo[ d ]thiazole-2(3 H )-thiones and benzo[ d ]thiazol-2(3 H )-ones has been developed through a temperature-controlled intermolecular [3 + 2] annulation of N,N-disubstituted arylhydrazines with CS 2 in the presence of DMSO. This protocol can obviate the prefunctionalization of the starting materials. This direct C-S/C-N bond formation reaction was performed in the absence of any external catalysts, transition metals, bases, ligands, and oxidants with high step economy.

An efficient copper-catalyzed aerobic oxidative cross-dehydrogenative coupling reaction for the synthesis of multisubstituted phosphorylhydrazides from N , N -disubstituted hydrazines and hydrogen phosphoryl compounds is accomplished. The reaction proceeds under mild conditions without the addition of any external oxidants and bases. This work reported here represents a direct P(═O)-N-N bond formation with the advantages of being operationally simple, good functional group tolerance, and high atom and step economy. Furthermore, the selected compounds exhibit potential inhibitory activity against tumor cells, which can be used in the field of screening of anticancer agents as new chemical entities.

A metal- and oxidant-free three-component desulfurization and deamination condensation of amidines, isothiocyanates, and hydrazines for the synthesis of structurally diverse fully substituted 1 H -1,2,4-triazol-3-amines is described. The reaction proceeds without the requirement of any external catalysts, metals, ligands, or oxidants. This [2 + 1 + 2] cyclization strategy involves C-N and C-S bond cleavage and the formation of new C-N bonds in one pot. This transformation provides a series of full substituted 1 H -1,2,4-triazol-3-amines with advantages of a broad substrates scope, mild reaction conditions, environmental friendliness, and easy gram-scale applications. The fluorescence and aggregation-induced emission (AIE) properties of selected products were further tested. These synthesized 1 H -1,2,4-triazol-3-amines may be worth investigating for further applications in the fields of organic chemistry, medicinal chemistry, and optical materials.

A new photocatalyst-free visible-light-enhanced strategy for the synthesis of pyrazolo[1,5- a ][1,3,5]triazine-2,4-diamines via the formation of electron donor-acceptor (EDA) complexes is reported. The in situ generated pyrazolthiourea intermediates from 1 H -pyrazol-3-amines and isothiocyanates undergo formal [4 + 2] annulation with 1,1,3,3-tetramethylguanidines (TMG) to deliver the corresponding products involved in three C-N bond formations in a one-pot protocol. The formation of EDA complex from pyrazolthiourea and TMG is confirmed by UV-vis spectroscopy and 1 H NMR experiments. Moreover, this mild reaction proceeds in the absence of any external transition metals, oxidants, bases, and ligands. This efficient methodology for the synthesis of purine analogues pyrazolo[1,5- a ][1,3,5]triazine-2,4-diamines provides potential synthetic applications in the field of drug research and development.