Synthesis and antibacterial activity of brominated 2′(4′)-nitro-3-hydroxy diphenyl ethers

Eight new brominated 2＇（4＇）-nitro-3-hydroxy diphenyl ethers have been designed and synthesized. The structures of new compounds were confirmed by ^1H NMR, IR and HRMS. The bioactivity tests showed that these compounds possessed antibacterial activities against the tested bacteria. These new compounds cannot be transformed into dioxins when they were manufactured and used.

Determination of the Amplification Factor for 2-Hydroxy-ethylperoxy Radicals in PERCA

A new method is proposed to determine the amplification factor for 2-hydroxy ethylperoxy radicals （HOC2H4O2·） in chemical amplifier. The radical source comes from the reaction of excess ethene with HO· radicals generated in the photolysis of water vapor at the wave length of 185 nm in air in a flow tube. This produces a radical source which contains equal amount of HO2·and HOC2H4O2·. The amplification factor is derived from the slopes of the lines between produced NO2 in chemical amplifier and total initial radical concentrations measured for the source of HO2· and that of the same amount of HO2· and HOC2H4O2· respectively. The amplification factor of HOC2H4O2· was similar to that of HO2·, indicating that HOC2H4O2· can be measured with the same sensitivity as HO2· by chemical amplifier.

A role for lipids as agents to alleviate stroke damage： the neuroprotective effect of 2-hydroxy arachidonic acid

Cerebrovascular accident（CVA）or stroke is one of the world＇s leading causes of death and permanent disability.The high social and medical costs associated with this pathology mean there is an urgent need to find effective therapies.Occlusion of the middle cerebral artery（MCAO）,mainly by clots,is the origin of most CVAs in humans.

Facile Resolution of Racemic 4-Phenyl-2-hydroxy Butyrate via Enzymatic Esterification and Transesterification

The optically active R-4-phenyl-2-hydroxy butyrates were prepared by esterification of the racemic acid or transesterification of the racemic ester catalyzed by lipase from Candida cyclindra (CCL) in organic media.

Interaction of N-(2-Methyl Thio Phenyl)-2-Hydroxy-1-Naphthaldimine with Tin Dioxide Nanoparticles: A Spectroscopic Approach

The interaction of N-(2-methyl thiophenyl)-2-hydroxy-1-naphthaldimine (NMTHN) with tin dioxide nanoparticles (SnO2 NPs) has been investigated by spectroscopic tools such as absorption and fluorescence spectroscopy. Absorption spectroscopy reveals the formation of ground state complex. Fluorescence spectroscopy has been used to study the signatures of fluorescence quenching. SnO2 NPs are found to quench the intrinsic fluorescence of NMTHN via static and dynamic quenching. The deviation from linearity in the Stern-Volmer plot has been observed.

Associations between Vitamin D and Type 2 Diabetes Mellitus: The Role of Vitamin D Receptor and Binding Protein

Background: Type 2 diabetes mellitus (T2DM) is a chronic disease that is characterized by β-cell dysfunction and resistance for insulin. Vitamin D is necessary for insulin secretion so it is a crucial factor in the development of T2DM. This study was done to investigate the association between serum 25-hydroxy Vitamin D [25(OH)3D], VDR (Vitamin D receptor) and VDBP (Vitamin D binding protein) with type 2 diabetic patients compared to control subjects. Subjects and Methods: This study carried out 110 female patients who were previously diagnosed with type 2 diabetes and 110 age, sex and weight matched as controls. All participants were subjected to full history taking, clinical examination and assessment of fasting blood glucose, HbA1c , lipid profile, 25-hydroxy Vitamin D [25(OH)3D], VDR and VDBP. Results: Results showed that the level of 25(OH)3D was significantly lower in diabetic group compared to controls and was significantly negatively correlated with glycated hemoglobin, serum total cholesterol and low density lipoprotein cholesterol in type 2 DM. Decreasing Vitamin D level was significantly associated with decreasing VDR. No significant association was found between Vit D and VDBP levels. Conclusions: Vitamin D deficiency is frequent in diabetic patients and associated with poor control and outcome. This suggests a role of Vitamin D in the pathogenesis and control of T2DM. Serum VDBP in diabetes may be independent to the level of 25(OH)3D and needs further studies.

羟丙基壳聚糖的研制和鉴定

此方法为壳聚糖水溶性的改性研究。指出了羟丙基壳聚糖的制备方法和鉴定结果 。

绵麦冬的化学成分研究

目的研究绵麦冬Ophiopogon japonicus(Thunb.)Ker.Gaw l.cv.M ianyangensis的化学成分。方法采用硅胶柱层析和制备薄层层析法进行分离,利用波谱数据鉴定结构。结果从绵麦冬乙酸乙酯提取部分分得4种高异黄酮类化合物,鉴定为oph iopogonanone A、2-′hydroxy-m ethyl oph iopogonone A、oph iopogonanone E和oph iopogonanone F。结论4种化合物均为首次从绵麦冬植物中分得。

Decreased paraoxonase1 activity and increased malondialdehyde and oxidative DNA damage levels in primary open angle glaucoma

To investigate the malondialdehyde（MDA） levels,paraoxonase1（PON1） activity and 8-hydroxy 2-deoxyguanosine（8-OHd G） levels in the primary open angle glaucoma（POAG） patient.Blood samples from 52 healthy individuals and 53 patients with POAG were analyzed for MDA and 8-OHd G by high-performance liquid chromatography（HPLC） and PON1 by spectrophotometry.The data obtained were analyzed statistically.MDA levels were 10.46±8.4 and 4.70±1.79 μmol; PON1 levels were 121 ±39.55 and 161.62 ±60.22 U/m L; and 8-OHd G values were1.32 ±0.53/10~6 d G and 0.47 ±0.27/10~6 d G in the POAG patients and the control group,respectively.The difference was significant in MDA levels,8-OHd G levels and PON1 activity in POAG patients in comparison with controls（P 〈0.001）.We concluded that the observed increase in MDA and 8-OHd G levels may be correlated with decreased PON1 activity.Oxidative stress plays an important role in glaucoma development.

Sulforaphane Protects Astrocytes Against Oxidative Stress and Delayed Death Caused by Oxygen and Glucose Deprivation

氧化应激是缺血再灌注后星形胶质细胞损伤和死亡的重要分子机制之一,可能成为有效的干预靶点。下述治疗策略可减轻缺血再灌注条件下产生的多种反应性氮氧化合物损伤。这种方法可通过使用化学试剂或适当条件促进转录活化因子NRF2从细胞浆转入细胞核,并与抗氧化基因反应位点结合,来诱导缺血再灌注后损伤细胞的Ⅱ期基因反应。本研究将验证如下假说:NRF2基因表达通路激活剂sulforaphane能对体外无氧无糖环境处理的培养皮质星形胶质细胞起神经保护作用。将皮质星形胶质细胞暴露于无氧无糖环境(OGD)4 h,于干预前48 h或干预后给予5μMsulforaphane(NRF2基因表达通路激活剂)培养48 h,两种培育条件下细胞死亡均明显减少。免疫细胞化学结果表明干预前给予sulforaphane处理,细胞中DNA/RNA氧化标志物8-hydroxy-2-deox-yguanosine的表达在恢复给氧4 h后降低,两种培育条件下胞浆内及胞核内NRF2的免疫反应均增强且NQO1(NRF2转录活化基因产物)的表达和酶活性均增强。本研究提示sulforaphane可通过激活NRF2抗氧化基因表达通路,减少体外缺氧再灌注后星形胶质细胞的死亡。

Properties of a New Dental Photocurable Matrix Resin with Low Shrinkage

In order to reduce the amount of volumetric shrinkage that occurs in dental composites as a result of curing,a new kind of dental matrix resin combining bisphenol-S-bis（3-meth acry late-2-hydroxy propyl）ether（BisS-GMA） with the expanding monomer unsaturated spiro orthoesters 2-methylene-1,4,6-trispiro[4,4] nonane （SOE） was prepared,with triethylene glycol dimethacrylate （TEGDMA） as diluent.CQ （camphorquinone） of 1wt% and DMAEMA （2-（dimethylamino） ethyl meth acrylate） of 2wt% were used as photoinitiation system to initiate the copolymerization of the matrix resins.The performance including volumetric shrinkage,degree of conversion and condition of the ring-opening reaction of SOE,as well as curing time and the tensile bond strength were investigated respectively by the dilatometer,Fourier transfer infrared,the universal testing machine,and so on.The ring-opening polymerization of SOE occurred.Meanwhile,the obtain copolymers were crosslinked.The matrix resin containing BisS-GMA and SOE showed a reduced amount of volumetric shrinkage at 1.52%,which is a promising strategy for obtaining a polymer with a low amount of volumetric shrinkage.Furthermore,the other properties were not compromised.

2-Hydroxymalonitrile——A Useful Reagent for One-step Synthesis of α-Hydroxy Esters

α-Hydroxy carboxylic esters and their derivatives are key substructures in a variety of biologically active natural products and numerous pharmaceuticals[1-3].A variety of methods for the synthesis of α-hydroxyesters via homologation of aldehydes or ketones have been developed and frequently used in organic synthesis[4-14].These approaches are generally based on the following routes（Scheme 1）.

Asymmetric synthesis of syn-aryl-(2S,3R)-2-chloro-3-hydroxy esters via an engineered ketoreductase-catalyzed dynamic reductive kinetic resolution

We report here a generic,green synthesis of 17 valuable syn-aryl-(2S,3R)-2–chloro-3–hydroxy esters(syn-(2S,3R)-1)in 73%-99%isolated yields along with 6.1:1–83:1 dr and 31%~>99%ee,through dynamic reductive kinetic resolution of racemic arylα–chloroβ-keto esters(2)catalyzed by an engineered ketoreductase which was obtained via ep PCR-based directed evolution.The hectogram scale synthesis of syn-(2S,3R)-1b at a substrate concentration of 120 g/L showcased the application potential of the biocatalytic method developed presently.

Synthesis of Chiral α-Benzyl-β^(2)-hydroxy Carboxylic Acids through Iridium-Catalyzed Asymmetric Hydrogenation of α-Oxymethylcinnamic Acids

An asymmetric hydrogenation of α-oxymethylcinnamic acids was developed by using chiral spiro phosphineoxazoline/iridium complexes as catalysts to prepare β^(2)-hydroxycarboxylic acids with high reactivity(TON up to 2000)and excellent enantioselectivity(up to 99.5%ee).By using this highly efficient asymmetric hydrogenation as a key step,a concise total synthesis of natural product homoisoflavone(S)-(+)-4 was accomplished.

Iodine-mediated regioselective hydroxyselenenylation of alkenes:Facile access to β-hydroxy selenides

In the presence of molecular iodine, the reaction of alkenes with diselenides proceeds efficiently under air and at room temperature in mixed solvent MeCN/H2O, which affording β-hydroxy selenides with high regioselectivity and in good to excellent yields. This iodine-mediated vicinal difunctionalization of alkenes requires mild reaction conditions and is a simple procedure, which extends the synthetic application of molecular iodine in organic synthesis.

披针叶茴香果实的化学成分研究

目的研究八角科（Illiciaceae）植物披针叶茴香（Illicium lanceolatum）果实的化学成分。方法应用硅胶、Sephadex LH-20、MCI等各种色谱技术进行分离纯化，根据化合物的理化常数和波谱数据鉴定其结构。结果从披针叶茴香果实的体积分数95％乙醇提取物中分离得到12个化合物，通过渡谱数据和理化常数分别鉴定为2，4-dihydroxy—allylbenzene-2-O-β-D—glucopyranoside（1），（＋）-儿茶素（2），槲皮素-3-O-β-L-鼠李糖苷（3），芦丁（4），异鼠李素-3-D-β-D-芸香糖苷（5），6-deoxy-1-hy—droxy neoanisatin（6），莽草毒素（7），icarisideE3（8），（75，8R）-urolignoside（9），对羟基苯甲酸（10），莽草酸（11），β-谷甾醇（12）。结论化合物1，4～6，8～10为首次从该植物中分离得到。

黄心卫矛的化学成分研究

目的研究黄心卫矛Euonymus macropterus Rupr.的化学成分。方法采用色谱技术分离纯化,并通过波谱技术及理化性质鉴定化合物结构。结果从黄心卫矛根部的乙醇提取物中分离得到6个化合物,分别鉴定为2-hydroxy hexacosanoicacid,ethyl ester(Ⅰ)、9,12-eicosadienoic acid(9Z,12Z)-,2-hydroxy-3-[[(9Z)-1-oxo-9-octadecen-1-yl]oxy]pro-pyl ester(Ⅱ)、表木栓醇(Ⅲ)、羽扇豆醇(Ⅳ)、二十烷醇(Ⅴ)、硬脂酸(Ⅵ)。结论以上化合物均首次从黄心卫矛中分离得到,其中,化合物Ⅰ、Ⅱ、Ⅴ、Ⅵ为首次从卫矛属植物中分离得到,化合物Ⅰ首次作为天然产物分离得到。