Two new xanthones from Polygala crotalarioides

Two new xanthones, 1,6,8-trihydroxy-7-methoxy-2,3-methylenedioxyxanthone (1) and 1,6-dihydroxy-7,8-dimethoxy-2,3-methylenedioxyxanthone (2), have been isolated from the roots of Polygala crotalarioides. Their structures were elucidated by spectral and chemical methods.     

Xanthones from the roots of Cudrania fruticosa Wight

Chemical investigation on the roots of Cudrania fruticosa resulted in the isolation of two new xanthones, 1,6,7-trihydroxy-2-(1,1-dimethyl-2-propenyl)-3-methoxyxanthone (1) and 3,6,7-trihydroxy-1-methoxyxanthone (2), together with three known ones, 1,3,5-trihydroxy-4-(3-hydroxy-3-methylbutyl)xanthone (3), 1,3-dihydroxy-6,7-dimethoxyxanthone (4) and 3,5,6-trihydroxy-1-methoxyxanthone (5), respectively. Their structures were elucidated on the basis of spectral and chemical techniques.     

彝药布高兹尔化学成分的分离和结构鉴定(Ⅰ)

应用高效多功能提取器,采用净化提取法等,从Veratrilla baillonii Franch根的石油醚和乙酸乙酯提出物中,分离获得6种(口山)酮类化合物。经光谱、理化常数鉴定为:1-羟基-2,3,4,7-四甲氧基(口山)酮(Ⅰ);1-羟基-2,3,4,5-四甲氧基(口山)酮(Ⅱ);1-羟基-3,4,5-三甲氧基(口山)酮(Ⅲ);1-羟基-2,3,5-三甲氧基(口山)酮(Ⅳ);1-羟基-3,4-二甲氧基-7-0-β-D-吡喃葡萄糖基(口山)酮(Ⅴ);1,7-二羟基-3,4-二甲氧基(口山)酮(Ⅵ)。乙醇、水提出物中各组分尚在研究中。     

彝药布高兹尔化学成分的分离和结构鉴定（Ⅱ）

本文继续报道Veratrills baillonii Franch根中分离得到的另外两个(口山)酮成分。现经光谱、理化常数鉴定,已确定为:1-羟基-2,3,5,6-四甲氧基(口山)酮(Ⅶ)及1-羟基-3,4,6-三甲氧基-7-0-β-D-吡喃葡萄糖基(口山)酮(Ⅷ)。此外,尚自乙醇提取液中分离并检出3个环烯醚萜类化合物,经聚酰胺薄膜层析,并与龙胆苦甙、獐牙菜苦甙等标准品对照,其中之一已初步确定为龙胆苦甙。     

口山酮抑制ox-LDL诱导的内皮细胞组织因子表达及机制研究

【目的】研究口山酮化合物去甲基雏菊叶龙胆酮(DMB)对氧化型低密度脂蛋白(ox-LDL)诱导的内皮细胞组织因子(TF)表达的影响及机制。【方法】培养人脐静脉内皮细胞,加入ox-LDL(0.2mg/mL)孵育24h诱导TF表达,一期凝固法和反转录PCR分别检测TF的活性和mRNA表达,用荧光试剂H2DCF-DA检测细胞内活性氧(ROS)的水平,EMSA检测核因子(NF)-κB活性。【结果】孵育ox-LDL(0.2mg/mL)24h能显著增加内皮细胞TF的活性和上调其mRNA表达,同时增加细胞内ROS生成和激活NF-κB。在加入ox-LDL前1h分别加入1、3或10μmol/LDMB能呈浓度依赖性地抑制ox-LDL诱导的TF活性和mRNA水平的增加。而且,DMB能显著降低ox-LDL诱导的细胞内ROS的生成增加和NF-κB的激活。【结论】DMB能抑制ox-LDL诱导的内皮细胞TF表达,其作用与抑制细胞内ROS生成和NF-κB激活有关。     

Substituted Xanthones as Antimycobacterial Agents,Part 2: Antimycobacterial Activity

A series of substituted xanthones was tested for their activity against four mycobacterial strains (Mycobacterium tuberculosis, M. avium, M. lufu, M. smegmatis) by determination of the minimum inhibitory concentrations (MIC values). For the most active compounds, supplementary characterisation was performed by bacterial growth kinetics, which allows a more precise interpretation of their antimycobacterial effects. From the test set, 1-methyl-2,4,7-trinitroxanthone ( 8a ) showed the highest antimycobacterial activity with a MIC value of 3 μg/mL against M. tuberculosis, which is comparable to the effect of well known drugs used in the treatment of tuberculosis. For all other compounds, the MIC values could not be determined, due to the comparatively low activity and to the poor solubility of the compounds, respectively. The semiquantitative evaluation of activity against the different strains of mycobacteria resulted in a classification into three activity classes, which will be used as dependent parameter in QSAR investigations, to be published in Part 3 of this series.     

高效液相色谱法测定大籽獐牙菜中有效成分的含量

目的:建立以高效液相色谱法测定大籽獐牙菜中1-羟基-3,7,8-三甲氧基酮、1,5,8-三羟基-3-氧基酮、1,8-二羟基-3,7-二甲氧基)酮和1,8-二羟基-3,5-二甲氧基酮含量的方法。方法:色谱柱为VP-ODSC18(150mm×4.60mm,5μm),流动相为甲醇-水-磷酸(70:30:0.4),检测波长为254nm,流速为1.0mL.min-1,柱温为20℃。结果:1-羟-基3,7,8-三甲氧基酮、1,5,8-三羟基-3-甲氧基酮、1,8-二羟基-3,7-二甲氧基酮和1,8-二羟基-3,5-二甲氧基咄酮进样量分别在0.172～0.86、0.224～1.344、0.144～0.72、0.154～0.77μg范围内线性关系良好,平均回收率(RSD)分别为98.18%(1.19%)、99.32%(1.52%)、98.44%(1.23%)、97.68%(1.57%)。结论:本方法快速、简便,结果准确、可靠。     

Inhibitors of bone resorption from <Emphasis Type="Italic">Halenia corniculata</Emphasis>

Eleven xanthones (1-11), three flavonoids (12-14) and three secoiridoids (15-17) were isolated from the aerial parts of Halenia corniculata. Among those compounds, 1-hydroxy-2,3,4,5-tetramethoxyxanthone (1), 1-hydroxy-2,3,4,7-tetramethoxyxanthone (2), 1-hydroxy-2,3,4,5,7-pentamethoxyxanthone (3), 1-hydroxy-2,3,5-trimethoxyxanthone (4), 1,8-dihydroxy-3,5-dimethoxyxanthone (7), and luteolin (12), at the concentration of 1 microg/mL, effectively inhibited the osteoclast differentiation in a co-culture system with mouse osteoblastic calvarial cells and bone marrow cells. Notably, compounds 1, 3, and 4 exhibited, in a dose-dependent manner, significant inhibition of osteoclast differentiation even at a low concentration (0.01 microg/mL). All the inhibitory compounds, except for compound 7, significantly reduced the pit formation on the dentine slice compared with the control group. For the survival of the mature osteoclasts, compounds 1-4 and 12 (1 microg/mL), significantly decreased the survival number through induction of cell apoptosis, and compound 4 exhibited a significant inhibitory effect on osteoclast survival even at the low concentration of 0.1 microg/mL.     

小无心菜中黄酮与酮类成分研究(英文)

运用溶剂萃取结合硅胶、Sephadex LH-20、ODS及半制备液相等色谱方法从小无心菜(Arenaria serpyllifolia L.)的全草中分离得到8个已知化合物。应用光谱技术鉴定其结构分别为槲皮素(1),槲皮素-7-O-α-L-鼠李糖苷(2),槲皮素-3-O-α-L-鼠李糖苷(3),3-O-甲基槲皮素(4),1,5-二羟基酮(5),1,5-二羟基酮-6-O-β-D-葡萄糖苷(6),5-羟基-1-甲氧基酮(7)和6-deoxyisojacareubin(8)。以上化合物均为首次从小无心菜中分离得到,化合物5–8为首次从蚤缀属植物中分离得到。     

Analysis of iridoids, secoiridoids and xanthones in Centaurium erythraea, Frasera caroliniensis and Gentiana lutea using LC-MS and RP-HPLC

This study presents a new and validated HPLC method for the simultaneous determination of bioactive compounds in Centaurium erythraea, Frasera caroliniensis and Gentiana lutea. The iridoid loganic acid, four secoiridoids and 29 xanthones were separated on a RP-18 column, using aqueous o-phosphoric acid (0.085%, v/v) and acetonitrile as mobile phase. Phytochemical investigation of C. erythraea herb and F. caroliniensis roots resulted into isolation of 25 xanthones and three secoiridoids the structure of which was elucidated by spectroscopic means (NMR, MS and UV). 1,3,8-Trihydroxy-5,6-dimethoxyxanthone, isolated from C. erythraea, turned out to be a novel xanthone. The stability of the analytes was tested by subjecting samples to light, moisture and different temperatures. After six months of storage, decomposition of gentiopicroside and sweroside was observed. The swertiamarin content was nearly unchanged when stored at room temperature or in the refrigerator, but high temperature conditions reduced the content to 85%. In contrast, xanthones were stable under long-term, refrigerated and accelerated conditions. The established chromatographic method has been successfully applied for the quantification of the bioactive compounds in the three plants. The presence and distribution of polyoxygenated xanthones within the three members of the Gentianaceae family and their significance as analytical markers are discussed.