新型吡啶-2-酮类衍生物的合成及生物活性

以3-氰基-5-乙酰基-6-甲基吡啶-2-酮(1a～1b)为原料,通过多步反应,合成了18种未见报道的含有均三唑并[3,4-b][1,3,4]噻二嗪或1,3,4-噁二唑啉的两类新型吡啶酮类化合物4a～4h,7a～7j,其结构经1H NMR,IR和MS及元素分析确证.利用单晶X射线衍射法测定了化合物4a的晶体结构.初步生测表明,部分化合物表现出不同的抗菌活性.     

一些2-氨基-1,3,4-噻二唑类化合物的合成及其对水稻白叶枯病菌活性的研究

为了筛选防治水稻白叶枯病的新药剂,合成了16个2-氨基-5-烷基-1,3,4-噻二唑(Ⅰ)(其中7个是新化合物),11个O,O-二苯基-N-(5-烷基-1,3,4-噻二唑-2-基)磷酰胺(Ⅱ)及4个O,O-二烷基-S-(N-1,3,4-噻二唑)胺基甲基二硫代磷酸酯(Ⅲ)。对水稻白叶枯病原菌和桃冠瘿病原菌进行了离体药效试验,结果表明Ⅰ、Ⅱ类化合物均有活性,且活性的大小与5-位正烷基的碳原子数有关。     

Photocatalytic Activity of LaSr2AlO5:Eu Ceramic Powders

The photocatalytic activity, of undoped and Europium‐doped LaSr₂AlO₅ powders, has been investigated by degrading methylene blue dye in water solutions. Those powders were fabricated by a combustion method and an annealing treatment in air. All samples showed a tetragonal single phase according to by X‐ray diffraction measurements (XRD). Scanning electron microscopy (SEM) revealed irregular semi‐oval grains with sizes in the range of 3.5–4.27 μm. Photoluminescence spectrum showed sharp emission peaks at 588 nm and at 617 nm which are associated with ⁷F₁,⁷F₂→ ⁵D₀ Eu³⁺ ion forbidden transitions, respectively, under UV light excitation of 322 nm. The methylene blue (MB) degradation under UV light (254 nm) was studied by monitoring changes in the absorbance peak of MB at 665 nm. Finally, LaSr₂AlO₅:Eu powders were used three times and the efficiency for the degradation of MB decreased from 100 to 61% after the third cycle of use.     

Metabolic Profiling of Inga Species with Antitumor Activity

This work evaluated the metabolic profiling of Inga species with antitumor potential. In addition, we described the antigenotoxicity of polyphenols isolated from I. laurina and a proteomic approach using HepG2 cells after treatment with these metabolites. The in vitro cytotoxic activity against HepG2, HT-29 and T98G cancer cell lines was investigated. The assessment of genotoxic damage was carried out through the comet assay. The ethanolic extract from I. laurina seeds was subjected to bioassay-guided fractionation and the most active fractions were characterized. One bioactive fraction with high cytotoxicity against HT-29 human colon cancer cells (IC₅₀ = 4.0 µg mL⁻¹) was found, and it was characterized as a mixture of p-hydroxybenzoic acid and 4-vinyl-phenol. The I. edulis fruit peel (IC₅₀ = 18.6 µg mL⁻¹) and I. laurina seed (IC₅₀ = 15.2 µg mL⁻¹) extracts had cytotoxic activity against the cell line T98G, and its chemical composition showed a variety of phenolic acids. The chemical composition of this species indicated a wide variety of aromatic acids, flavonoids, tannins, and carotenoids. The high concentration (ranging from 5% to 30%) of these polyphenols in the bioactive extract may be responsible for the antitumor potential. Regarding the proteomic approach, we detected proteins directly related to the elimination of ROS, DNA repair, expression of tumor proteins, and apoptosis.     

Synthesis and Antitumor Activity of 4-tert-Butyl-5-benzyl-2-benzyliminothiazoles

A series of novel Schiff bases including 4-tert-butyl-5-benzyl-2-benzyliminothiazoles was synthesized by reacting the aromatic aldehydes with the corresponding 2-aminothiazoles.The antitumor bioassay revealed that compounds 2n and 2m exhibited potent cytotoxicity against human cervix cancer（HeLa） cell line with IC50 values of 0.001 and 0.007 mmol/L,respectively.The preliminary structure-activity relationship（SAR） investigations and the apoptosis evaluation suggest that 4-tert-butyl-5-benzyl-2-benzyliminothiazoles may be a satisfactory backbone for antitumor activity,and compound 2n can serve as an attractive candidate for the development of novel apoptosis in anticancer treatment.     

CeO2对催化剂银物种及CO氧化性能的影响

采用共浸渍、不同分步浸渍的方法制备了8 wt% Ag/CeO2-SiO2催化剂,运用XRD、UV-Vis、BET等多种手段对催化剂的结构进行表征,考察了其对CO氧化的活性,并初步探讨了助剂CeO2对催化剂结构及活性物种的影响。实验结果表明,添加1 wt% CeO2的8 wt% Ag/SiO2催化剂表现出较好的低温CO催化活性,随后氢气预处理明显提高了催化剂的反应活性。XRD和UV-Vis谱图表明少量的CeO2（1 wt%）有利于金属银物种的形成,并且能够提高Ag粒子的稳定性,高温处理不易聚集。高CeO2负载量下的催化剂中银物种主要以银簇（ ）形式存在。     

3-甲基-5-苯基-2-芳基吗啉盐酸盐合成及其抗实验性抑郁活性

苯基氨基乙醇;芳基吗啉;合成;抗抑郁活性     

5-亚环己基-2-取代氨基咪唑啉酮类化合物的合成及其杀菌活性研究

以环己酮和2-硫代乙内酰脲为起始原料,经Knoevenagel缩合反应制得5-亚环己基-2-硫代咪唑啉-4-酮(1),化合物1在乙醇钠/乙醇体系中与碘甲烷反应得到5-亚环己基-2-甲硫基咪唑啉-4-酮(2),化合物2再与相应的取代苯胺或苄胺在冰醋酸体系中回流制得目标化合物5-亚环己基-2-取代氨基咪唑啉酮3a～3r,它们的化学结构经1H NMR,IR,MS和X-ray单晶衍射确证.5-亚环己基-2-对氯苄氨基咪唑啉酮(3q):Mr=335.83,C16H18ClN3O CH4O,Monoclinic,P2(1)/n,ρ=1.264 g/cm3,F(000)=712,Z=4,a=0.59895(12)nm,b=1.2161(2)nm,c=2.4289(5)nm,β=94.03(3)°.初步生物活性测定结果表明:在50μg/mL浓度下,部分目标化合物均对供试菌种显现出一定的抑制活性,其中5-亚环己基-2-对氟苄氨基咪唑啉酮(3p)对油菜菌核的EC50为24.37μg/mL,3q对辣椒疫霉的EC50为28.68μg/mL.     

Visible-Light-Induced Bactericidal Activity of Vanadium-Pentoxide (V2O5)-Loaded TiO2 Nanoparticles

The bactericidal activity of TiO₂ nanoparticles under visible light is very important in regards to its practical applications. In this paper, we synthesized vanadium-pentoxide-loaded TiO₂ nanoparticles (V₂O₅?CTiO₂) using a chemical vapor condensation method, followed by the impregnation method, and characterized its physicochemical properties through X-ray diffraction patterning, X-ray photoelectron spectroscopy analysis, Raman spectra analysis, and Fourier transform infrared analysis. In addition, the antibacterial activity of V₂O₅?CTiO₂ nanoparticles against E. coli was evaluated and compared with pure TiO₂ nanoparticles. In these experiments, the population of E. coli was shown to be significantly reduced by V₂O₅?CTiO₂ nanoparticles under illumination with fluorescent light, whereas pure TiO₂ nanoparticles showed about 3.3-fold lower antibacterial activity than the V₂O₅?CTiO₂ nanoparticles. This result was most likely due to the change in surface conditions of the TiO₂ nanoparticles, which was due to the loading of vanadium pentoxide on the TiO₂ nanoparticles. Furthermore, both photocatalysts showed similar antibacterial activity under UV-A (352?nm) irradiation.     

A Review on the Biological Activity of Camellia Species

Medicinal plants have been used since antiquity to cure illnesses and injuries. In the last few decades, natural compounds extracted from plants have garnered the attention of scientists and the Camellia species are no exception. Several species and cultivars are widespread in Asia, namely in China, Japan, Vietnam and India, being also identified in western countries like Portugal. Tea and oil are the most valuable and appreciated Camellia subproducts extracted from Camellia sinensis and Camellia oleifera, respectively. The economic impact of these species has boosted the search for additional information about the Camellia genus. Many studies can be found in the literature reporting the health benefits of several Camellia species, namely C. sinensis, C. oleifera and Camellia japonica. These species have been highlighted as possessing antimicrobial (antibacterial, antifungal, antiviral) and antitumoral activity and as being a huge source of polyphenols such as the catechins. Particularly, epicatechin (EC), epigallocatechin (EGC), epicatechin-3-gallate (ECG), and specially epigallocatechin-3-gallate (EGCG), the major polyphenols of green tea. This paper presents a detailed review of Camellia species’ antioxidant properties and biological activity.     

Design,synthesis, and biological evaluation of new ALDH2 activators

Mitochondrial aldehyde dehydrogenase 2 (ALDH2) is an important enzyme response for the metabolism or detoxification of toxic aldehydes, in particular acetaldehyde and 4-hydroxynonenal (4-HNE), which were important risk factors for acute alcoholism and stroke respectively. A special variant ALDH212 with reduced enzymatic activity was carried by a high percentage of East Asians, especially Han Chinese, and that could increase the risk of these diseases further. Therefore, ALDH2 activators had important potential clinical values. N-benzylbenzamide compounds represented by Alda-1 were the only ALDH2-specific activators that have been reported so far. In this study, three new classes of compounds were modified from Alda-1 to improve their water-solubility and then drug-like properties. The results showed that all compounds had increased water solubility and two classes of compounds exhibited good activation activity. Among them, compound I-6 showed the best activity.     

Enhancement of Catalytic Activity for Benzene Hydroxylation over Novel V2O5/HZSM-5 Catalyst

Kinetics and Catalysis - In this paper, a novel V2O5/HZSM-5 catalyst was prepared and characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy,...     

Evolution of Gold Species in an Au/CeO2 Catalyst and Its Impact on Activity for CO Oxidation

An Au/ceria(0.44%, mass fraction) catalyst containing gold ions was prepared by a modified deposition precipitation method, and the evolution of gold ions in the catalyst and its influence on the catalysis of CO oxidation were investigated. It was found that the as-prepared catalyst containing gold ions with high valence could fully oxidize CO at –10 °C initially but was deactivated gradually at low temperatures during the reaction with CO or treatment by unpurified air. The deactivation of the catalyst during CO oxidation or treatment of it by unpurified air was independent and progressive at low temperatures while the activity of the catalyst at relatively high temperatures was maintained well. During the reaction with CO or treatment by unpurified air, the XPS results indicate that gold species evolved from high valence to low valence and the diffuse reflectance UV-Vis spectra show that high valence gold was reduced to charged gold clusters, gold clusters grew to small gold crystals and small gold crystals grew to large gold particles. Accordingly, the high valence gold corresponded to the activity at low temperatures and the metallic gold was active and relatively stable at high temperatures. The turnover frequencies(TOF) of the catalysts treated by different methods at 273 K decreased with the evolution of gold species from high valence to low valence, no maximum of TOF was observed although gold particles in the catalyst attained to about 2―3 nm during the treatment. An Au/ceria catalyst with a gold load of 0.87% (mass fraction) maintained a good activity for CO oxidation within 18 h at room temperature. The catalysts were characterized via transmitted electronic microscopy(TEM), inductively coupled plasma optical emission spectrometry(ICP-OES), X-ray diffraction(XRD) and BET specific surface area and UV-Vis DRS as well.     

Synthesis and Antimicrobial Activity of Substituted 5-Cyano-6-oxo-2-styrylnicotinic Acids

Derivatives of the anilide or ethyl ester of 5-cyano-6-oxo-2-styrylnicotinic acid are formed in the reaction of the anilide or ethyl ester of 5-cyano-2-methyl-6-oxonicotinic acid with aromatic aldehydes. On interaction with hydrazine hydrate the products are converted into hydrazides of 5-cyano-6-oxo-2-styrylnicotinic acid derivatives.     

2-取代氨基-5-去氢枞基-1,3,4-噁二唑衍生物的合成及除草活性

以去氢枞酸为原料,经酰化后与水合肼反应合成去氢枞酰肼3,再与芳基异硫氰酸酯反应,得到中间体1-去氢枞酰基-4-取代基氨基硫脲4,4在Hg(OAc)2/EtOH条件下关环,合成得到一系列新型2-取代氨基-5-去氢枞基-1,3,4-噁二唑化合物5.采用IR,MS,1HNMR,13C NMR和元素分析等方法对中间体4和目标产物5进行了分析和表征.初步的除草活性测试表明,化合物4和5对油菜的胚根生长以及对稗草的幼苗生长有一定的抑制作用,其中化合物4d在浓度为100mg/L时对油菜胚根生长的抑制率达88.2％.     

N-芳基-5-芳基-2-呋喃甲酰胺和N-5-芳基-2-呋喃甲酰基-N''''-芳氧基乙酰基肼的合成及生物活性的研究

5-芳基-2-呋喃甲酸及其衍生物具有调节植物生长等作用[4].我们通过大量的实验,选用PTC法,利用5-芳基-2-呋喃甲酰氯与芳胺和芳氧基乙酰胼反应,合成了新化合物Ⅱ和Ⅳ:     

钼镍负载催化剂表面组份及其活性的研究

利用X光光电子能谱(XPS)，激光拉曼光谱(LRS)和程序升温还原(TRP)等技术，研究了高载钼量的负载钼镍催化剂的表面组份形式．结果表明，催化剂在氧化态、还原态、硫化态时表面的主要组份分别以类似NiMoO_4结构的NiMo_xO_y多种价态钼酸盐及金属镍，氧硫钼镍及硫化钼形式存在．三种化学态的加氢脱硫活性顺序为硫化态，还原态>>氧化态．还原态表面检测到金属镍，据此提出了金属镍所产生的氢溢流效应是还原态活性明显增加的一个原因．文中由硫化态、还原态表面组份与反应活性之间的关联结果支持了Kwart提出的多点催化反应机理．     

四种药用香薷植物中多种微量元素分析

对高原香薷、萼果香薷、密花香薷、细穗香薷等四种药用香薷植物中的17种微量元素含量进行了测定和分析。结果表明,4种香薷植物中常量元素以K含量最高,其次为Ca、Mg、Na;必需微量元素中以Cu、Fe、Mn元素的含量为高;非必需微量元素As、Hg、Pb、Cd、Sb含量较低,从重金属元素的角度考虑,使用所测定的4种香薷植物是安全的。