龙脑樟枝中一个新的桉叶烷型倍半萜内酯类化合物

研究龙脑樟Cinnamomum camphora chvar.Borneol枝的化学成分。利用硅胶、Sephadex LH-20葡聚糖凝胶、MCI等柱层析,结合制备型高效液相色谱技术从龙脑樟枝乙酸乙酯萃取段中分离纯化得到3个化合物,通过波谱学数据和文献报道确定了它们的结构,分别为campholactone A(1)、northalifoline(2)、N-苯乙基-苯甲酰胺(3)。其中化合物1为新的桉叶烷型倍半萜内酯类化合物,在C-11位上存在罕见的酰胺取代,化合物2、3为首次从龙脑樟中分离得到。采用MTT法对化合物1~3进行人肝癌HepG2细胞增殖毒性评价,通过脂多糖刺激RAW 264.7小鼠巨噬细胞建立的体外炎症模型,采用Griess法研究化合物1~3对炎症介质NO生成的影响。实验结果显示化合物1~3在浓度为20μmol/L时,对肿瘤细胞HepG2表现不同程度的抑制作用,抑制率分别为35.78%±0.15%、42.36%±0.58%、23.95%±0.40%;对脂多糖诱导的RAW 264.7小鼠巨噬细胞释放炎症因子NO的抑制作用弱,抑制率小于20%。

中药崖柏化学成分、药理作用及其应用前景研究

崖柏为珍稀物种,其根、叶、花等部位含有多种活性成分,在替代药物及保健食品开发中极具价值。本文通过对崖柏的专利及论文搜索平台统计整理,综合分析了崖柏的挥发油、树脂、木质素、黄酮类、多糖类等5大类主要化学成分;对崖柏的抗菌作用、抗炎作用、抗氧化作用、抗肿瘤、抗虫、抗辐射药理作用以及毒性和安全性情况进行了总结;梳理了已上市的崖柏产品相关情况;探讨限制崖柏发展的因素包括产品同质化严重,制剂工艺粗糙、剂型单一,产学研合作不足,主产区种植和产量极少的问题;提出了崖柏未来发展前景,并提出3点发展的建议,即开发崖柏各部位的保健与营养价值,扩充适合崖柏的剂型和产品,加强政策支持力度,深化产学研合作,为我国崖柏药品及保健食品的产业发展提供新思路。

Stable CuO/La_(2)Sn_(2)O_(7) catalysts for soot combustion:Study on the monolayer dispersion behavior of CuO over a La_(2)Sn_(2)O_(7) pyrochlore support

To understand the dispersion behavior of metal oxides on composite oxide supports and with the expectation of developing more feasible catalysts for soot oxidation,CuO/La_(2)Sn_(2)O_(7)samples containing varied CuO loadings were fabricated and characterized by different techniques and density functional theory calculations.In these catalysts,a spontaneous dispersion of CuO on the La_(2)Sn_(2)O_(7)pyrochlore support formed,having a monolayer dispersion capacity of 1.90 mmol CuO/100 m^(2) La_(2)Sn_(2)O_(7)surface.When loaded below this capacity,CuO exists in a sub-monolayer or monolayer state.X-ray photoelectron spectroscopy(XPS),Raman spectroscopy,and Bader charge and density of states analyses indicate that there are strong interactions between the sub-monolayer/monolayer CuO and the La_(2)Sn_(2)O_(7)support,mainly through the donation of electrons from Cu to Sn at the B-sites of the structure.In contrast,Cu has negligible interactions with La at the A-sites.This suggests that,in composite oxide supports containing multiple metals,the supported metal oxide interacts preferentially with one kind of metal cation in the support.The Raman,in situ diffuse reflectance infrared Fourier transform spectroscopy,and XPS results confirmed the formation of both O2^(-)and O2^(2-)as the active sites on the surfaces of the CuO/La_(2)Sn_(2)O_(7)catalysts,and the concentration of these active species determines the soot combustion activity.The number of active oxygen anions increased with increase in CuO loading until the monolayer dispersion capacity was reached.Above the monolayer dispersion capacity,microsized CuO crystallites formed,and these had a negative effect on the generation of active surface oxygen sites.In summary,a highly active catalyst can be prepared by covering the surface of the La_(2)Sn_(2)O_(7)support with a CuO monolayer.

Investigation of lattice capacity effect on Cu2+-doped SnO2 solid solution catalysts to promote reaction performance toward NOx-SCR with NH3

To understand the effect of the doping amount of Cu^2+ on the structure and reactivity of SnO2 in NOx-SCR with NH3, a series of Sn-Cu-O binary oxide catalysts with different Sn/Cu ratios have been prepared and thoroughly characterized. Using the XRD extrapolation method, the SnO2 lattice capacity for Cu^2+ cations is determined at 0.10 g Cu O per g of SnO2, equaling a Sn/Cu molar ratio of 84/16. Therefore, in a tetragonal rutile SnO2 lattice, only a maximum of 16% of the Sn4+ cations can be replaced by Cu^2+ to form a stable solid solution structure. If the Cu content is higher, Cu O will form on the catalyst surface, which has a negative effect on the reaction performance. For samples in a pure solid solution phase, the number of surface defects increase with increasing Cu content until it reaches the lattice capacity, as confirmed by Raman spectroscopy. As a result, the amounts of both active oxygen species and acidic sites on the surface, which critically determine the reaction performance, also increase and reach the maximum level for the catalyst with a Cu content close to the lattice capacity. A distinct lattice capacity threshold effect on the structure and reactivity of Sn-Cu binary oxide catalysts has been observed. A Sn-Cu catalyst with the best reaction performance can be obtained by doping the SnO2 matrix with the lattice capacity amount of Cu^2+.

毛梗豨莶草化学成分研究Ⅱ

目的：本课题组前期对自建的江西100种中草药提取物组分库样品进行活性筛选时，发现毛梗稀莶草Siegesbeckia glabrescens的二氯甲烷和乙酸乙酯萃取部位具有显著的抑制细胞程序性坏死的生理活性。为明确毛梗稀莶草的活性组分，本课题组对毛梗稀莶草二氯甲烷和乙酸乙酯萃取部位进行系统化学成分分离，以期寻找具有抑制细胞程序性坏死的目标化合物。方法：采用正相硅胶柱色谱（二氯甲烷-甲醇20：1-0：1），反相ODS柱色谱（30％-100％甲醇），LH-20羟丙基葡聚糖凝胶柱色谱、重结晶等方法对毛梗稀莶草二氯甲烷和乙酸乙酯萃取部位进行分离和纯化，根据理化性质及’H．NMR，13C-NMR波谱数据进行化合物结构鉴定。结果：从毛梗稀莶草中分离并纯化出9个化合物，分别鉴定为2-methoxy-4-（2-propen-1-y1）penyl-6-acetate-β-D-glucopyranoside（1），苄醇嵋-D-吡喃葡萄糖苷（2），香豆素（3），棕榈酸（4），咖啡酸乙酯（5），反式对羟基肉桂酸（6），β-谷甾醇（7），卢-胡萝卜苷（8），豆甾醇（9）。结论：化合物1-6为首次从该植物中分离得到。

毛梗豨莶草黄酮类化学成分分离鉴定

目的:本课题组前期对自建的江西100种中草药提取物组分库样品进行活性筛选时,发现毛梗豨莶草Siegesbeckia glabresce的乙酸乙酯萃取部位具有显著的抑制细胞程序性坏死的生理活性。为明确毛梗豨莶草的活性组分,本课题组对毛梗豨莶草乙酸乙酯萃取部位进行系统化学成分分离,以其寻找具有抑制细胞程序性坏死的目标化合物。方法:采用正相硅胶柱色谱(二氯甲烷-甲醇,20∶1~0∶1),反相ODS柱色谱(30%~100%甲醇),Sephadex LH-20柱色谱、重结晶等方法对毛梗豨莶草乙酸乙酯萃取部位进行分离和纯化,根据理化性质及~1H-NMR,^(13)C-NMR波谱数据进行化合物结构鉴定。结果:此次报道从毛梗豨莶草中分离并纯化的9个黄酮类化合物,分别鉴定为:3,4-二甲氧基-2',4'-二羟基查尔酮(1);7-O-(β-Dglucopyranosyl)-galactin(2);7,3',4'-三羟基黄酮(3);5,6,7,3',4',5'-六甲氧基黄酮(4);8,3',4'-三羟基-7-甲氧基二氢黄酮(5);5,4'-二羟基-7,3'-二甲氧基二氢黄酮醇(6);7,4'-二羟基-3'-甲氧基二氢黄酮(7);木犀草素(8);槲皮素(9)。结论:化合物1~7为首次从该植物中分离得到。