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1.
从青蕨的乙酸乙酯提取物中分离得到6个化合物,通过化学方法及波谱分析,分别将其结构鉴定为木香素Ⅲ(1),7-甲氧基鬼灯擎素(2),扶桑甾醇(3),5-(3′-甲基丁基)-8-甲氧基呋喃香豆素(4),2-(3′-羟基-3′-甲基)丁基-4-羟基-5-甲氧基苯酚-1-O-β-D匍吡喃糖苷(青蕨素Ⅰ)(5)和2-(3′-羟基-3′-甲基)丁基-4-羟基-3,6-二甲氧基苯酚-1-O-β-D-匍吡喃糖苷(青蕨素Ⅱ)(6)。化合物5和6为新化合物,化合物1,2,3和4为首次从该植物中分离得到。  相似文献   

2.
吊石苣苔中的化学成分   总被引:5,自引:0,他引:5  
新鲜吊石苣苔全草用70%丙酮水溶液组织破碎提取,然后经Diaion HP-20,Toyopearl HW-40,硅胶等柱色谱技术进行分离纯化得到8个化合物,经波谱分析鉴定为5,7-二羟基-6,8,4′-三甲氧基黄酮(1),丁香酸(2),邻苯二甲酸-双-(2-乙基己基)酯(3),5,7-二羟基-6,8,4′-三甲氧基黄酮醇(4),7-羟基-6,8,4′-三甲氧基-5-O--βD-葡萄糖黄酮苷(5),7-羟基-6,8,4′-三甲氧基-5-O-[-βD-葡萄糖-(1→6)]--βD-葡萄糖黄酮苷(6),4′,5-二羟基-7-甲氧基-6-C--βD-葡萄糖黄酮苷(7)和4′,5-二羟基-6,7-二甲氧基-8-C-β-D-葡萄糖黄酮苷(8)。除7-羟基-6,8,4′-三甲氧基-5-O--βD-葡萄糖黄酮苷和7-羟基-6,8,4′-三甲氧基-5-O-[β-D-葡萄糖-(1→6)]--βD-葡萄糖黄酮苷外,其余6个化合物均为首次从该植物中分离得到。  相似文献   

3.
从连香树(Cercidiphyllum japonicum Sieb. et Zucc.)树皮中分离到8个化合物。其中7个为黄酮醇,1个为酚酸类成分。经理化测定和波谱解析,分别鉴定为5,7-二羟基-3,8,4′-三甲氧基黄酮 (Ⅰ)、3,5,7-三羟基-8,4′-二甲氧基黄酮 (Ⅱ)、5,7,4′-三羟基-3,8-二甲氧基黄酮 (Ⅲ)、3,5,7,4′-四羟基-8-甲氧基黄酮 (Ⅳ)、3,5,7,4′-四羟基黄酮 (Ⅴ)、5,7-二羟基-8,4′-二甲氧基黄酮-3-O-葡萄糖甙 (Ⅶ)、5,7,4′-三羟基-8-甲氧基黄酮-3-O-葡萄糖甙 (Ⅷ)和没食子酸乙酯 (Ⅵ)。其中化合物Ⅶ为未见报道的新化合物。除化合物Ⅴ外,其余化合物均为首次从该属植物中分得。  相似文献   

4.
香薷中的化学成分   总被引:8,自引:0,他引:8  
从香[Eltholtzia ciliata(Thund.)Hyland]中分出14个化合物,用波谱和化学等方法确定为6-甲基三十三烷(Ⅰ),13-环己基二十六烷(Ⅱ),β-谷甾醇(Ⅲ),棕榈酸(Ⅳ_a),亚油酸(Ⅳ_b),亚麻酸(Ⅳ_c),熊果酸(Ⅴ),5-羟基-6、7-二甲氧基黄酮(Ⅵ),5-羟基-7、8-二甲氧基黄酮(Ⅶ),5、7-二羟基-4′-甲氧基黄酮(Ⅷ),5-羟基-7、4′-二甲氧基双氢黄酮醇(Ⅸ),β-谷甾醇-3-β-D-葡萄糖甙(Ⅹ),5-羟基-6-甲基-7-O-α-D-半乳吡喃糖双氢黄酮甙(Ⅺ),刺槐素-7-O-β-D-葡萄糖甙(Ⅻ)。其中化合物Ⅺ为新化合物,除(Ⅳ_b)和(Ⅳ_c)外,其余为首次从该属植物中得到。  相似文献   

5.
四方蒿的化学成分   总被引:3,自引:0,他引:3  
从唇形科植物四方蒿(Elsholtzia blanda (Benth.)Benth.)中分离得到9个化合物,用光谱分析、化学方法及与已知化合物对照,分别鉴定为:5,6-二氢-6-苯乙类吡喃-2酮(1)、木栓桐(2)、4-羟基-3-甲氧基苯乙烯(3)、5,2′-二甲氧基-6,7-二氧亚甲基双氢黄酮(4)、5-羟基07-甲氧基-6-O[α-L-鼠李糖(1→2)-β-D-岩藻糖]黄桐甙(5),5,5′-二羟基-7-乙酰氧基6,8,3″,3″-四甲基吡喃(3′,4′)黄酮(6)、5,5′-二羟基-5-(α-甲基)丁酰氧基-6,8,3″,3″-四甲基吡喃(3′,4′)黄酮(7)、5,5′-二羟基-6,7-二氧亚甲基-8,3″,3″-三甲基吡喃(3′,4′)黄酮(8)和丁香酸葡萄糖甙(9)。其中,6、7、8为新化合物,分别命名为四方蒿素Ⅰ、Ⅱ和Ⅲ。  相似文献   

6.
旱前胡的化学成分   总被引:2,自引:0,他引:2  
从云南产早前胡(Ligusticum daucoides Franch.)(伞形科)根的脂溶性部分分离了11个化合物,分别为香豆素化合物:columbianadin,isoedultin,archangelicin,旱前胡甲素(daucoidin A),旱前胡乙素(dsucoidin B),佛手柑内酯(bergapten),非香豆素化合物:falcarindiol(7),阿魏酸(ferulic acid),蜡酸(cerotic acid),β-谷甾醇(β-sitosterol),胡萝卜甙(daucosterol)。其中,化合物4和5是新的香豆素化合物,经化学方法及光谱测定,证明其结构为:4是3′去乙酰基isoedultin,即:2′(S)-(1″,1″-二甲基,1″-当归酰氧基)-3′(R)-羟基-角型二氢呋喃香豆素[2′(S)-(1″,1″-dimethvl,1″-angelovloxv)—3′(R)-hydroxy angular dihydrofuranocoumarin];5是2′-(1″-甲基,1″-羟基,1″-当归酰氧亚甲基)-角型二氢呋喃香豆素[2′-(1″-methyl,1″-hydroXy,1″-angeloyloxy-methylene)angular dihydrofuranocoumarin]。  相似文献   

7.
苦皮藤中酚性成分抗羟自由基活性研究   总被引:7,自引:0,他引:7  
从苦皮藤中分离出四个酚性成分 :( )儿茶素 ( 1) ,(— ) -表儿茶素 ( 2 ) ,3,4 ,5-三甲氧基 -苯 - 1- O- β- D-葡萄糖甙 ( 3)和 3,7,4 -三羟基 - 3 -甲氧基黄烷 - 5- O- β- D-葡萄糖甙 ( 4 )。其中 ( 4 )为新化合物。用电子自旋共振技术 ( ESR)研究了它们对羟自由基即(· OH)的清除作用。  相似文献   

8.
连钱草化学成分研究   总被引:6,自引:2,他引:4  
从连钱草(Glechoma longituba)分离并鉴定了10个化合物,分别为β-谷甾醇(1)、齐敦果酸(2)、熊果酸(3)、2α,3α-二羟基乌苏-12-烯-28-酸(4)2、α,3β-二羟基乌苏-12-烯-28-酸(5)、胡萝卜苷(6),3,6-二甲氧基-6″,6″-二甲基苯并吡喃-(7,8,2″,3″)-黄酮(7)、芫花素(8)、芹菜素-7-O--βD-葡萄糖苷(9)、木犀草素-7-O-β-D-葡萄糖甙(10)。其中化合物2,4~8首次从该植物中分离得到。  相似文献   

9.
中华青荚叶的一个新果糖酯   总被引:1,自引:0,他引:1  
从山茱萸科中华青荚叶( Helwingia chinensis )的乙醇提取物中分离得到一个新果糖酯和十个已知化合物.通过现代波谱技术分别鉴定为:2- O -(E)-咖啡酰-3- O -(3, 5-二甲氧基香豆酰)-α-D-呋喃果糖甙(1),2- O -β-D-呋喃果糖基α-D-异吡喃糖酯(2),甘草甜素(3),4′-羟基-7- O -葡萄糖-2, 3-二羟黄酮甙(4),黄豆甙(5),5-葡萄糖芹菜甙(6),7- O -葡萄糖芹菜甙(7),4- O -葡萄糖香豆酸(8), 葡萄糖咖啡酸(9), 3β-赤杨醇(10), 薯蓣皂甙3- O -{α-L-鼠李糖吡喃糖基(1→2)-[α-L-阿拉伯呋喃糖基(1→3)]-β-D-葡萄糖吡喃糖} (11).  相似文献   

10.
连香树树皮化学成分的研究   总被引:2,自引:0,他引:2  
从连香树(CercidiphyllumjaponicumSieb.etZucc.)树皮中分离到8个化合物。其中7个为黄酮醇,l个为酚酸类成分。经理化测定和波谱解析,分别鉴定为:5,7-二羟基-3,8,4'-三甲氧基黄酮(Ⅰ)、3,5,7-三羟基-8,4'-二甲氧基黄酮(Ⅱ)、5,7,4'-三羟基-3,8-二甲氧基黄酮(Ⅲ)、3,5,7,4'-四羟基-8-甲氧基黄酮(Ⅳ)、3,5,7,4'-四羟基黄酮(Ⅴ)、5,7-二羟基-8,4'-二甲氧基黄酮-3-O-葡萄糖甙(Ⅶ)、5,7,4'-三羟基-8-甲氧基黄酮-3-O-葡萄糖甙(Ⅷ)和没食子酸乙酯(Ⅵ)。其中化合物Ⅶ为未见报道的新化合物。除化合物Ⅴ外,其余化合物均为首次从该属植物中分得。  相似文献   

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It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.  相似文献   

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Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.  相似文献   

18.
Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.  相似文献   

19.
肝癌中HBV和HCV基因和抗原的分布及意义   总被引:1,自引:0,他引:1  
采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细  相似文献   

20.
For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.  相似文献   

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