FeBr_3-catalyzed dibromination of alkenes and alkynes

The dibromination of alkenes and alkynes with bromosuccinimide and sodium bromide catalyzed by FeBr₃ under mild conditions has been developed.The trans-dibromo compounds were exclusively obtained with excellent yields.     

Design,synthesis and in vivo anti-hyperglycemic activity of gem-dimethyl-bearing C-glucosides as SGLT2 inhibitors

A series of gem-dimethyl-bearing C-glucosides were designed and synthesized as SGLT2 inhibitors,with anhydrous aluminum chloride-mediated Friedel-Crafts alkylation to construct the gem-dimethyl functionality being the key step.The in vivo anti-hyperglycemic activity was evaluated with mice oral glucose tolerance test(OGTT),and all the synthesized compounds showed significant but less potent anti-hyperglycemic activity than the positive control dapagliflozin.     

锥光干涉法表征偶氮苯侧链液晶聚合物的光致取向

采用偏光显微镜在平行光和锥光条件下对液晶聚合物膜内分子的取向排列状态进行了研究,不同取向状态的膜由线偏振光或圆偏振光照射偶氮苯侧链液晶聚合物得到。结果表明,液晶聚合物膜采用线偏振光照射时,偶氮苯介晶基元沿面排列,形成单相畴面内取向态。该取向态的锥光干涉图为位于视场中心的粗黑十字,旋转载物台小于10°,该干涉图即完全退出...     

Generation of anti-trenbolone monoclonal antibody and establishment of an indirect competitive enzyme-linked immunosorbent assay for detection of trenbolone in animal tissues, feed and urine

Trenbolone (TRE) is a steroid used by veterinarians on livestock to increase appetite and body weight. The use of TRE has been restricted because of its harmful side effect for consumers. To effectively control TRE residue in food and food product, a rapid and convenient immunoassay was developed by preparing an anti-TRE monoclonal antibody. The immunogen and coating antigen were prepared by coupling TRE hapten with carrier proteins via 1-ethyl-3-(dimethylaminopropyl)carbodiimide hydrochloride (EDC) method. The optimized method gave an average IC₅₀ value of 0.323 ng mL⁻¹ towards TRE and an average detection limit (LOD) of 0.06 ng mL⁻¹, which is much lower than the maximum residue levels (2.0 ng g⁻¹) accepted by the Joint FAO/WHO Expert Committee on Food Additives (JECFA). The specificity of the antibody was evaluated by measuring cross-reactivity of six structurally related compounds, including 19-nortestosterone (9.7%), testosterone (0.13%), methyltestosterone (<0.01%), methandrostenolone (<0.01%), (+)-dehydroisoandrosterone (<0.001%) and β-estradiol (<0.001%). The recovery rates of the test in detection of TRE-fortified animal tissue, urine and animal feed samples were in the range of 81.3-89.4%, while the intra- and inter-assay coefficients of variation were less than 12.0%.     

Graphene oxide noncovalent photosensitizer and its anticancer activity in vitro

Graphene oxide (GO) was investigated as a potential drug-delivery system due to its special properties and biocompatibility. Thus far, little has been done to use GO as a photosensitive drug-delivery system and to explore its anticancer activity in vitro in photodynamic therapy applications. Here, a novel GO-hypocrellin A (GO-HA) hybrid was prepared by a simple noncovalent method and its photodynamic activity was studied for the first time. The results showed that an efficient loading amount of HA on GO was as high as 1.0 mg mg(-1) and the stability of the hybrid was superior to that of the free hypocrellin A in aqueous solution. Furthermore, GO-HA can be excited by irradiation with light of appropriate wavelength to generate singlet oxygen, and in vitro experiments illustrated that GO-HA was efficiently taken up by tumor cells, and that light irradiation of such impregnated cells resulted in significant cell death. Thus, these properties of GO-HA could possibly make it especially promising for use in clinical photodynamic therapy.     

Investigation on the Performance of Supported Molybdenum Carbide for the Partial Oxidation of Methane

The performance of uspported and unsupported molybdenum carbide for the partial oxidation of methane (POM) to syngas was investgated.An evaluation of the catalysts indicates that bulk molybdenum carbied has a higher methane conversion during the initial stage but a lower selectivity to CO and H2/CO ratio in the products.The rapid deactivation of the catalyst is also a significant problem.However,the supported molybdenum carbide catalyst shows a much higher methane conversion,increased selectivity and significantly improved catalytic stability.The characterization by XRD and BET specific area measurements depict an improved dispersion of molybdenum carbide when using alumina as a carrier.The bulk or the supported molybdenum carbide exists in the β-Mo2C phase,while it is transformed into molybdenum dioxide postcatalysis which is an improtant cause of molybdenum carbide deactivation.     

金属-聚哇烷-硅结构的电容-电压特性

设计了metal-polysilane-silicon(MPS)结构.首次发现MPS结构具有电容-电压(C-V)特性,许多MPS结构的C-V曲线平带电压为正,且其C-V特性与聚硅烷枝化度一致,即随着聚硅烷枝化度提高,MPS结构C-V曲线明显向电压轴正向漂移.聚硅烷MPS结构有望设计成测定聚硅烷枝化度装置.     

Facile optical resolution of tert-butanethiosulfinate by molecular complexation with (R)-BINOL and study of chiral discrimination of the diastereomeric complexes

An important synthon, tert-butanethiosulfinate (2), has been effectively resolved by forming molecular complexes with (R)-2,2'-dihydroxy-1,1'-binaphthyl (BINOL, 3) in high enantioselectivity (>99 % ee). The present procedure represents the first example of the resolution of thiosulfinate. The mechanism of chiral discrimination is discussed in terms of molecular recognition based on IR and Xray analyses of the diastereomeric complexes during the resolution. In the less-soluble complex, (R)-3 and (R)-2 self-assembled as a linear supramolecule; however, in the more-soluble complex, (R)-3 and (S)-2 formed a simple bimolecular complex by one stronger hydrogen bond. Hydrogen bonding is the major driving force for effective resolution.     

Effects of different oxygen-containing anions on the structure of water clusters

Using Ni(Im)₆²⁺ (Im = imidazole) as the structural unit, the effects of oxygen-containing anions, such as SO₄^2-, NO₃^? and CO₃^2- on the structure of water clusters were studied. The crystal structures of three compounds [Ni(Im)₆][SO₄(H₂O)₁₁] (1), [Ni(Im)₆][(NO₃)Cl(H₂O)₄] (2), and [Ni(Im)₆][CO₃(H₂O)₅] (3) were obtained. Using Mercury-3.8 software to analyze the above three crystal structures, find different anion of water clusters had a significant effect on the supramolecular structure. At the same time, it also significantly influences the number of water molecules in the crystal structure.