BINOL-phosphoric acids-catalyzed furylogous pinacol rearrangement of 1-[5-(hydroxy-diaryl-methyl)-furan-2-yl]-cyclobutanols into spiro cyclopentanones

A BINOL-phosphoric acid-catalyzed furylogous Pinacol rearrangement is developed. This reaction produces spiro cyclopentanone in good yields under mild conditions. The enantioselective version of this reaction is also investigated using chiral phosphoric acid (CPA) as the catalyst.     

STUDY ON THE NON-COVALENT INTERACTION OF APIGENIN MOLECULARLY IMPRINTED POLYMERS BY SPECTROMETRY

The non-covalent interaction between aPigenin （API） and different functional monomers （α-methylacrylic acid （MAA）, acrylamide （AM）, 2-vinylpyridine （2-Vpy） and combined functional monomers （AM/2-Vpy）） was determined by UV spectrometry, and a series of apigenin molecularly imprinted polymers （API-MIPs） was synthesized with different functional monomers through molecular imprinting technology. The relationship between the non-covalent interaction of template/functional monomer and absorption of MIPs also was studied. The results showed that the order of the strength of the non-covalent interaction between API and different functional monomers in tetrahydrofuran （THF） is as follows： 2-Vpy〉 AM/2-Vpy〉AM〉MAA, which is positive correlation to the absorption capability of corresponding MIPs, and 2-Vpy is the optimum functional monomer among the used monomer for preparing API- MIPs.     

Water‐in‐Supercritical CO2 Microemulsion Stabilized by a Metal Complex

Herein we propose for the first time the utilization of a metal complex for forming water‐in‐supercritical CO₂ (scCO₂) microemulsions. The water solubility in the metal‐complex‐stabilized microemulsion is significantly improved compared with the conventional water‐in‐scCO₂ microemulsions stabilized by hydrocarbons. Such a microemulsion provides a promising route for the in situ CO₂ reduction catalyzed by a metal complex at the water/scCO₂ interface.     

First separation of four aromatic acids and two analogues with similar structures and polarities from Clematis akebioides by high‐speed counter‐current chromatography

In this paper, we report an efficient method by high‐speed counter‐current chromatography for the first separation of four aromatic acids and two analogs with similar structures and polarities from Clematis akebioides. First, the ethyl acetate extract was treated by silica gel column chromatography to enrich the target compounds. And then the fraction with target compounds were purified by high‐speed counter‐counter chromatography using a two‐phase solvent system consisting of chloroform/acetonitrile/water (10:6:4, v/v). The results showed high‐speed counter‐current chromatography could be a powerful technology for the separation of compounds with similar structures and polarities. Besides, it was found acetonitrile could be a good methanol substitute when a chloroform/methanol/water system could not provide a good separation factor. This study provides a reference for the separation of compounds from Clematis akebioides.     

具有聚集诱导发光效应的咔唑基三苯乙烯衍生物单体及聚合物

合成了一类新的咔唑基三苯乙烯衍生物单体及其聚合物.利用示差扫描量热法(DSC)、热重分析法(TGA)、紫外可见分光光度法和荧光分光光度法等对单体和聚合物的性能进行了初步的表征.实验结果表明,该单体和聚合物具有较高的玻璃化转变温度(Tg),分别为210℃和229℃;单体和聚合物均具有很高的热稳定性,热失重5%的温度分别为466℃和467℃;单体具有明显的聚集诱导发光性能(AIE),而聚合物则具有聚集诱导增强发光性能(AIEE);所合成的单体和聚合物有望在OLED器件以及化学传感器上得到应用.     

Novel porous CuO microrods: synthesis,characterization, and their photocatalysis property

Porous copper oxide microrods have been synthesized via calcining copper glycinate monohydrate microrod precursor which was prepared in mild conditions without any template or additive. Several techniques, such as X-ray diffraction, field emission scanning electron microscopy, thermogravimetric analysis, Fourier transform infrared spectroscopy, and Brunauer–Emmett–Teller (BET) N₂ adsorption–desorption analyses, were used to characterize the structure and morphology of the products. Scanning electron microscopy (SEM) analyses show that the precursor consists of a large quantity of uniform rod-like micro/nanostructures with typical lengths in the range of 25–40 µm and diameters in the range of 0.1–0.35 µm. The microrod-like precursors transformed into porous microrod products after calcination at 450 °C in flow air for 2 h. The BET surface area of the porous CuO microrods was calculated to be 8.5 m² g⁻¹. In addition, the obtained porous CuO microrods were used as catalysts to photodegrade rhodamine B (RhB), methyl orange, methylene blue, eosin B, and p-nitrophenol. Compared with commercial CuO powders, the as-prepared porous CuO microrods exhibit superior properties on photocatalytic decomposition of RhB due to their porous hierarchical structures.     

Effect of trabecular bone material properties on ultrasonic backscattering signals

In this study, ultrasonic backscattering signals in cancellous bones were obtained by finite difference time domain （FDTD） simulations, and the effect of trabecular material properties on these signals was analyzed. The backscatter coefficient （BSC） and integrated backscatter coefficient （IBC） were numerically investigated for varying trabecular bone material properties, including density, Lame coefficients, viscosities, and resistance coefficients. The results show that the BSC is a complex function of trabecular bone density, and the IBC increases as density increases. The BSC and IBC increase with the first and second Lame coefficients. While not very sensitive to the second viscosity of the trabeculae, the BSC and IBC decrease as the first viscosity and resistance coefficients increase. The results demonstrate that, in addition to bone mineral density （BMD） and microarchitecture, trabecular material properties significantly influence ultrasonic backseattering signals in cancellous bones. This research furthers the understanding of ultrasonic backscattering in cancellous bones and the characterization of cancellous bone status.     

MiR-1224-5p modulates osteogenesis by coordinating osteoblast/osteoclast differentiation via the Rap1 signaling target ADCY2

MicroRNAs (miRNAs) broadly regulate normal biological functions of bone and the progression of fracture healing and osteoporosis. Recently, it has been reported that miR-1224-5p in fracture plasma is a potential therapy for osteogenesis. To investigate the roles of miR-1224-5p and the Rap1 signaling pathway in fracture healing and osteoporosis development and progression, we used BMMs, BMSCs, and skull osteoblast precursor cells for in vitro osteogenesis and osteoclastogenesis studies. Osteoblastogenesis and osteoclastogenesis were detected by ALP, ARS, and TRAP staining and bone slice resorption pit assays. The miR-1224-5p target gene was assessed by siRNA-mediated target gene knockdown and luciferase reporter assays. To explore the Rap1 pathway, we performed high-throughput sequencing, western blotting, RT-PCR, chromatin immunoprecipitation assays and immunohistochemical staining. In vivo, bone healing was judged by the cortical femoral defect, cranial bone defect and femoral fracture models. Progression of osteoporosis was evaluated by an ovariectomy model and an aged osteoporosis model. We discovered that the expression of miR-1224-5p was positively correlated with fracture healing progression. Moreover, in vitro, overexpression of miR-1224-5p slowed Rankl-induced osteoclast differentiation and promoted osteoblast differentiation via the Rap1-signaling pathway by targeting ADCY2. In addition, in vivo overexpression of miR-1224-5p significantly promoted fracture healing and ameliorated the progression of osteoporosis caused by estrogen deficiency or aging. Furthermore, knockdown of miRNA-1224-5p inhibited bone regeneration in mice and accelerated the progression of osteoporosis in elderly mice. Taken together, these results identify miR-1224-5p as a key bone osteogenic regulator, which may be a potential therapeutic target for osteoporosis and fracture nonunion.Subject terms: Translational research, Cell signalling     

Tuning Internal Strain in Metal–Organic Frameworks via Vapor Phase Infiltration for CO2 Reduction

A gas-phase approach to form Zn coordination sites on metal–organic frameworks (MOFs) by vapor-phase infiltration (VPI) was developed. Compared to Zn sites synthesized by the solution-phase method, VPI samples revealed approximately 2.8 % internal strain. Faradaic efficiency towards conversion of CO₂ to CO was enhanced by up to a factor of four, and the initial potential was positively shifted by 200–300 mV. Using element-specific X-ray absorption spectroscopy, the local coordination environment of the Zn center was determined to have square-pyramidal geometry with four Zn−N bonds in the equatorial plane and one Zn-OH₂ bond in the axial plane. The fine-tuned internal strain was further supported by monitoring changes in XRD and UV/Visible absorption spectra across a range of infiltration cycles. The ability to use internal strain to increase catalytic activity of MOFs suggests that applying this strategy will enhance intrinsic catalytic capabilities of a variety of porous materials.     

Synthesis and Evaluation of a Macrocyclic Actinium-225 Chelator,Quality Control and In Vivo Evaluation of 225Ac-crown-αMSH Peptide

Targeted alpha-therapy (TAT) has great potential for treating a broad range of late-stage cancers by delivering a focused and lethal radiation dose to tumors. Actinium-225 (²²⁵Ac) is an emerging alpha emitter suitable for TAT; however, the availability of chelators for Ac remains limited to a small number of examples (DOTA and macropa). Herein, we report a new Ac macrocyclic chelator named ‘ crown’ , which binds quantitatively and rapidly (<10 min) to Ac at ambient temperature. We synthesized ²²⁵Ac- crown -αMSH, a peptide targeting the melanocortin 1 receptor (MC1R), specifically expressed in primary and metastatic melanoma. Biodistribution of ²²⁵Ac- crown -αMSH showed favorable tumor-to-background ratios at 2 h post injection in a preclinical model. In addition, we demonstrated dramatically different biodistrubution patterns of ²²⁵Ac- crown -αMSH when subjected to different latency times before injection. A combined quality control methodology involving HPLC, gamma spectroscopy and radioTLC is recommended.