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1.
Aucubinine B (4), a monoterpene alkaloid obtained from the metabolites of aucubin in the presence of human intestinal bacteria, has been synthesized from 3-bromo-4-pyridinecarboxaldehyde (5) in four steps with 39% overall yield. The construction of the cyclopenta[c]pyridine intermediate (7) was realized by an intramolecular Heck reaction.  相似文献   

2.
杨小宝  花成文  翟宏斌 《有机化学》2004,24(11):1429-1431
Aucubinine A是自aucubin在人类大肠杆菌存在时的代谢产物中分离得到的一种单萜生物碱.本课题组实现了起始于4-氢-5-羟基-3-亚甲基-5H-环戊二烯[2,1-c]吡啶(6)对aucubinine A的首次合成,总产率为30%.硼氢化以及随后的在碱性介质中的氧化将6转化为两个非对映异构的二醇7,然后经苄位选择性氧化生成aucubinine A.  相似文献   

3.
氮杂类聚合大环化合物的合成   总被引:1,自引:0,他引:1  
梁书锋  花成文  杨小宝  乔泽邦 《有机化学》2008,28(11):1986-1988
以间苯二甲酰氯为原料, 分别与二(4-氨基苯基)甲烷、二(4-氨基苯基)醚及二(4-氨基苯基)砜通过一步反应合成了3种新的[3+3]氮杂类聚合大环化合物, 产率分别为41%, 40%和36%; 并通过元素分析, IR, 1H NMR,13C NMR和MS对其结构进行了表征.  相似文献   

4.
以(3R,4R)-4,7,7-三甲基-6-氧杂二环[3,2,1]辛烷-3,4-二醇(1)和乙酰氯(2)为原料,经"一锅法"制得混合物Ⅰ;Ⅰ经分离纯化得4个新型的双官能单萜氧杂二环二醇乙酸酯类衍生物(3a~3d),其结构经1H NMR,13C NMR,FT-IR和HR-MS表征。考察了物料比r[n(2)∶n(1)]和反应时间对3a~3d相对浓度的影响。结果表明,在反应条件[1 5 mmol,r=7,回流反应7 h]下,3a~3d的相对浓度分别为21.6%,15.6%,37.9%和24.9%;在反应条件[1 5 mmol,r=4,回流反应7 h]下,3a~3d的相对浓度分别为50.7%,36.6%,7.84%和4.86%。用培养皿法测试了1和3a~3d的除草活性。实验结果表明,1和3a~3d均能显著抑制一年生黑麦草胚根与胚芽生长;在用药浓度为5 mmol·L-1时,1和3a~3d对根长抑制率分别为55.1%,86.0%,84.2%,91.3%和97.5%;对芽长抑制率分别为55.1%,76.5%,92.8%,94.8%和98.4%。  相似文献   

5.
A series of novel pinanyl pyrimidine amine derivatives (1e~1n) and camphoryl pyrimidine amine derivatives (2b~2f) bearing bicyclic monoterpene moieties were designed and synthesized from natural and renewable nopinone and camphor. All chemical structures of target compounds were characterized by 1H NMR, 13C NMR and HRMS spectra analyses, and the antimicrobial activities were evaluated. The results indicated that most compounds showed considerable antibacterial and antifungal activities against Klebsiella pneumoniae, Streptococcus pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, Methicillin-Resistant Staphylococcus aureus (MRSA), Bacillus cereus and Candida albicans. Among them, 1f showed potent antibacterial activity against all tested bacteria, 1i exhibited excellent inhibition against Streptococcus pneumoniae (1 μg/mL) and Escherichia coli (1 μg/mL), which was better than the control drug amikacin (2 μg/mL). As to antifungal activity against Candida albicans (C. albicans), compound 1l showed comparable activity (16 μg/mL) to the control drug ketoconazole. Furthermore, five active compounds with better antimicrobial activities also showed anti-inflammatory potencies against mouse mononuclear macrophages leukemia cells (RAW). Especially, 1f (IC50 = 1.37 μM) and 2f (IC50 = 1.87μM) are more potent than the control drug aspirin (IC50 = 1.91 μM).  相似文献   

6.
This paper describes a fully automated, multidimensional, double-oven GC-GC system, developed in our laboratory. The system is based on the use of mechanical valves which allow the multitransfer of different fractions during the same GC analysis and the use of the two GC independently when the multitransfer options is not used. Pneumatic and electronic circuits permit maintenance of constant retention times in the pre-column, even for the components eluted after numerous transfers. The system has been used for the determination of the enantiomeric distribution of β-pinene, sabinene, limonene, linalol, terpinen-4-ol, and α-terpineol in lemon oils. The results obtained allowed the characterization of cold-pressed lemon oils.  相似文献   

7.
Nucleophilic addition of secondary phosphine oxides to furfural takes place under mild conditions and gives quantitative yields of 2-(diorganylphosphorylhydroxymethyl)furans, which are polyfunctional building blocks for organic synthesis and prospective amphiphilic ligands for the design of metal complex catalysts.  相似文献   

8.
采用柠檬酸盐法合成出La0.6Sr0.4Co0.8Fe0.2O3钙钛矿复合氧化物超细粉料,考查了各种影响溶胶与凝胶的形成以及合成粉料晶体结构与颗粒形态的因素,并确定了最佳的合成条件。研究了烧成温度对La0.6Sr0.4Co0.8Fe0.2O3电导率的影响,发现1200℃是最合适的烧成温度。研究结果表明,在室温~900℃范围内,样品的电导率在600℃附近出现峰值(~103S·cm-1),在低温段样品的导电行为符合小极化子导电机制,不同烧成温度的样品的导电活化能基本一致(5.31~5.79kJ·mol-1)。与常规固相合成法相比,柠檬酸盐法合成的La0.6Sr0.4Co0.8Fe0.2O3具有更高的烧结活性和电导率。  相似文献   

9.
水热条件下,合成了新的金属有机骨架[Cu(Hbtc)(bmix)0.5]n(1)(H3btc=1,3,5-苯三甲酸,bmix=1,4-二(2-甲基咪唑基-1-亚甲基)苯)。单晶X射线衍射分析表明,该配合物属正交晶系,Pbcn空间群,晶胞参数为a=1.436 30(9) nm,b=1.477 15(11) nm,c=1.543 48(10) nm,V=3.274 7(4) nm3,Z=8。配合物1中,Hbtc2-以四连接方式与铜中心配位,bmix桥连配体进一步修饰网络结构,最终1显示为1个(4,5)节点的三维的网络结构,其Schl?fli 符号为(42·5·62·8)(42·53·63·7·8)。此外还研究了配合物的热稳定性和对光助类芬顿反应降解甲基橙的催化性质。  相似文献   

10.
水热条件下,合成了两个新的配位聚合物[Cd(PhCOO)2(bmix)]n(1)和{[Cd(chdc)(bmix)].C2H5OH}n(2)(bmix=1,4-双(2-甲基咪唑基-1-甲基)苯,H2chdc=1,4-环己二酸)。单晶结构分析表明,配合物1为一维锯齿状链结构平行于[001]平面;配合物2为层状结构,镉原子通过双配体桥连形成四连接的二维(4,4)网络。两个配合物中镉原子均具有6配位的畸变八面体几何构型,另外,测定了两个配合物的热稳定性。  相似文献   

11.
The key role of trivalent manganese (Mn(III)) species in promoting sulfate radical-based advanced oxidation processes (SR-AOPs) has recently attracted increasing attention. This review provides a comprehensive summary of Mn(III) (oxyhydr)oxide-based catalysts used to activate peroxymonosulfate (PMS) and peroxydisulfate (PDS) in water. The crystal structures of different Mn(III) (oxyhydr)oxides (such as α-Mn2O3, γ-MnOOH, and Mn3O4) are first introduced. Then the impact of the catalyst structure and composition on the activation mechanisms are discussed, as well as the effects of solution pH and inorganic ions. In the Mn(III) (oxyhydr)oxide activated SR-AOPs systems, the activation mechanisms of PMS and PDS are different. For example, both radical (such as sulfate and hydroxyl radical) and non-radical (singlet oxygen) were generated by Mn(III) (oxyhydr)oxide activated PMS. In comparison, the activation of PDS by α-Mn2O3 and γ-MnOOH preferred to form the singlet oxygen and catalyst surface activated complex to remove the organic pollutants. Finally, research gaps are discussed to suggest future directions in context of applying radical-based advanced oxidation in wastewater treatment processes.  相似文献   

12.
IntroductionAntimony freePb Caalloyshavecommonlybeenusedinthemanufactureofgridsinordertominimizegassingineitherlow maintenanceorvalve regulatedleadacidbatteries .However ,thesealloyscancauseotherproblemssuchasprematurecapacityloss ,lowcharge ac ceptanceand…  相似文献   

13.
The effects of samarium on the properties of the anodic Pb(II) oxides films formed on lead at 0.9 V (vs. Hg/Hg2SO4) in 4.5 mol/L H2SO4 solution were studied using linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS) and scanning electron micrographs (SEM). The experimental results show that adding Sm to lead metal can inhibit the growth of the Pb(II) oxides film effectively, and reduce the resistance of the PbO oxides film obviously. The addition of Sm increases the porosity of the anodic film, which may cause the increase of the ionic conductance produced by the interstitial liquid among the PbO particles in the film and lead to the decrease of the resistance of the anodic film.  相似文献   

14.
Betula platyphylla Suk., whose bark and juice are used as anti-inflammatory and cough relieving agent1, is widespread in China. Previous investigations of this plant have led to the isolation of various compounds2,3. We herein report structural elucidation of a new monoterpene glucoside (1) isolated from the leaves of Betula platyphylla Suk.. Only two monoterpene glucosides isolated from Betula L. have been published until now4.Compound 1 was obtained as colorless needles (EtOAc), mp 64.5~…  相似文献   

15.
尿素反应法制备介孔Ni-Mo复合氧化物   总被引:1,自引:0,他引:1  
采用尿素反应法合成出具有介孔结构的Ni-Mo复合氧化物。用XRD、低温氮气吸附-脱附表征、HRTEM、TG-DTA、FTIR等分析手段对所合成的Ni-Mo复合氧化物及其前躯体进行了表征,并确定了制备Ni-Mo复合氧化物适宜的焙烧温度。以2%二苯并噻吩(DBT)溶液为模型化合物,在固定床连续高压微反装置上考察了介孔Ni-Mo复合氧化物作为催化剂的加氢脱硫(HDS)性能。尿素反应法合成的Ni-Mo复合氧化物具有较高的比表面积,达到124 m2·g-1,适宜的孔容0.22 mL·g-1,和理想的孔径分布,平均孔径为5.8 nm。HDS活性评价表明,这种催化剂具有较高的脱硫率和加氢活性,在反应温度为280 ℃时脱硫率可达100%,远高于对比催化剂Ni-Mo/Al2O3。  相似文献   

16.
Catharanthus roseus is a well-known traditional herbal medicine for the treatment of cancer, hypertension, scald, and sore in China. Phytochemical investigation on the twigs and leaves of this species led to the isolation of two new monoterpene indole alkaloids, catharanosines A (1) and B (2), and six known analogues (3–8). Structures of 1 and 2 were established by 1H-, 13C- and 2D-NMR, and HREIMS data. The absolute configuration of 1 was confirmed by single-crystal X-ray diffraction analysis. Compound 2 represented an unprecedented aspidosperma-type alkaloid with a 2-piperidinyl moiety at C-10. Compounds 6–8 exhibited remarkable Cav3.1 low voltage-gated calcium channel (LVGCC) inhibitory activity with IC50 values of 11.83 ± 1.02, 14.3 ± 1.20, and 14.54 ± 0.99 μM, respectively.  相似文献   

17.
合成并通过红外光谱、元素分析、单晶及粉末衍射表征了3个一维配合物[Ln(HDTTA)3(CH3OH)3]n(Ln=Ce(1),Pr(2),Sm(3))的结构(D-H2DTTA为(+)-二(对甲苯酰)-D-酒石酸).单晶衍射结果表明,3个配合物同构,结晶于三方晶系手性空间群R3,在c方向呈现一维链状结构.荧光光谱表明由于...  相似文献   

18.
本文以环状单萜醇α-萜品醇、L-薄荷醇及链状单萜醇香叶醇、香茅醇为先导化合物,采用酰氯酯化法合成肉豆蔻酸α-萜品醇酯(TER-C14)、肉豆蔻酸-L-薄荷醇酯(MEN-C14)、肉豆蔻酸香叶醇酯(GER-C14)和肉豆蔻酸香茅醇酯(CIT-C14),并考察单萜醇及其肉豆蔻酯作为促透剂对布南色林(Blo)的促透效果。通过体外经皮渗透实验、体外释放实验和分子模拟技术初步探究单萜醇及其肉豆蔻酯的促透机制。结果显示,当GER-C14或CIT-C14为促透剂时,均有显著的促透效果(P<0.05),并且24h经皮累积透过量是空白组的4.84倍和4.45倍。促透机制为肉豆蔻酸单萜醇酯破坏药物与神经酰胺之间的氢键相互作用,增加脂质迁移率和药物的自由能,从而促进药物的渗透。肉豆蔻酸单萜醇酯有望作为新型促透剂在经皮给药系统中广泛应用。  相似文献   

19.
系列纳米结构锰氧化物的水热合成   总被引:2,自引:0,他引:2  
以KMnO4为锰源、抗坏血酸(AA)为还原剂,采用水热法制备系列纳米结构锰氧化物。通过调节反应物的物质的量的比、水溶液的pH值、反应温度和反应时间,制备出了不同纳米结构的锰氧化物,包括Mn3O4纳米粒子、MnOOH、α-MnO2和β-MnO2纳米棒。采用XRD和TEM测试技术对合成产物进行了表征,同时对其反应机理进行了探讨。  相似文献   

20.
Abstract

Phosphine, generated from elemental phosphorus in the system KOH-toluene-H2O, reacts with vinyl sulfides under free radical conditions (AIBN, dioxane, 65–70°C, atmospheric pressure) to form regiospecifically tris[2-(organylthio)ethyl]phosphines, which are readily oxidized in air to corresponding tris[2-(organylthio)ethyl]phosphine oxides.  相似文献   

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