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1.
A novel C30 sterol, (22E, 24ξ)-24-n-propylcholest-7, 22-dien-3β-ol (racemosol, 1), along withscopoletin (2), scopolin (3), umbelliferone (4), methylβ-D-frucopyranoside (5), syringaresinol-4-O-β-D-glucopyranoside (6), quercetin-3-O-β-D-glucopyranoside (7), quercetin-3-O-α-L-rhamnopyranoside (8),eupatilin (9), kaempferol-3-O-β-D-glucopyranoside (10) and (E)-N-2-(2,3-dihydroxyphenyl) ethyl cinnamamide(11), was isolated from the whole plants of Porana racemosa Roxb. Their structures were elucidatedpredominantly by spectral evidence.  相似文献   

2.
翅子树叶中的化学成分研究   总被引:2,自引:1,他引:1  
从翅子树叶中首次分离和鉴定了二个黄酮类化合物:多羟基黄烷(一)-epicatechin(1),多羟基黄酮 Quercetin-3-O-α-L-arabinopyranoside(2);一个五环三萜Lup-20(29)-en-3β-01(3)。  相似文献   

3.
Two New Triterpenoid Saponins from Akebia quinata (Thunb.) Decne.   总被引:1,自引:0,他引:1  
Two new triterpenoid saponins, hederagenin 3-O-α-L-arabinopyranosyl-(1→〉2)-α-L-arabinopyranoside named akeboside La (compound 1), oleanolic acid 3-O-α-L-arabinopyranosyl-(1→〉2)-β-D-glucopyranoside named akeboside Lb (compound 2), along with five known saponins, oleanolic acid 3-O-α-L-rhamnopyranosyl-(1→〉2)-α-L- arabinopyranoside (compound 3), hederagenin 3-O-α-L-rhamnopyranosyl-(1→〉2)-α-L-arabinopyranoside (compound 4), oleanolic acid 3-O-β-D-xylopyranosyl-(1→〉3)-α-L-rhamnopyranosyl-(1→〉2)-α-L-arabinopyranoside (compound 5), 3-O-α-L-rhamnopyranosyl-(1→〉2)-α-L-arabinopyranosyl oleanolic acid 28-O-α-L-rhamnopyranosyl-(1→〉4)-α-D- glucopyranosyl-(1→〉6)-β-D-glucopyranoside (compound 6), 3-O-α-L-rhamnopyranosyl-(1→〉2)-α-L-arabinopyranosyl hederagenin 28-α-L-rhamnopyranosyl-(1→〉4)-β-D-glucopyranosyl-(1→〉6)-β-D-glucopyranoside (compound 7) were isolated from the n-butanol part of the 80% ethanol extracts of the dried stems of Akebia quinata (Thunb.) Decne. Compound 5 was isolated from plants of genus Akebia for the first time. The structures were elucidated on the basis of physicochemical properties and spectral data.  相似文献   

4.
为研究白花洋紫荆(Bauhinia variegata var.candida)花的化学成分,以白花洋紫荆花的乙醇提取物为对象,运用葡聚糖凝胶柱层析、MCI柱层析、半制备高效液相色谱等方法进行分离纯化,根据化合物的核磁共振波谱数据进行结构鉴定。结果从白花洋紫荆花中分离纯化得到17个化合物,包括1个葡萄糖苷类、2个苯甲酸类、2个香豆酸类、1个多环酚类,11个黄酮类,分别鉴定为β-D-甲基葡萄糖苷(1)、对羟基苯甲酸甲酯(2)、对甲氧基苯甲酸(3)、对香豆酸(4)、对甲氧基桂皮酸(5)、pacharin(6)、柚皮素(7)、异牡荆苷(8)、山柰酚(9)、6-羟基山奈酚3-O-葡萄糖甙(10)、山柰酚-3-O-鼠李糖苷(11)、百蕊草素(12)、kaempferol 3-O-α-L-rhamnopyranosyl-(1→6)-β-D-lucopyranoside(13)、槲皮素(14)、3-O-甲基槲皮素(15)、quercetin-3-O-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside(16)、quercetin-3-O-(6″-O-α-L-rhamnopyranosyl)-β-D-glucoside(17)。本研究得到的化合物均为首次从该植物中分离得到。共筛选了化合物10、12、13、14、17的胰脂肪酶活性,结果显示该5个化合物对胰脂肪酶均具有一定的抑制活性。  相似文献   

5.
从十齿花的地上部分分离得到11个化合物,经理化方法和光谱分析鉴定为3,3'-二甲氧基鞣酸-4'-鼠李糖苷(1)、槲皮素-3-O-β-D-葡萄糖苷(2)、3,3'-二甲氧基鞣酸-4'-葡萄糖苷(3)、isolariciresinol-9-O-α-L-arabinopyranoside(4)、对苯二酚(5)、对羟基苯甲酸(6)、α-hydroxy-(4-hydroxyphenyl)acetonitrile(7)、6-O-methyldhurrin(8)、3,3',4',5,7-五羟基黄烷(9)、对羟基苯甲醛(10)、槲皮素-3-O-β-L-鼠李糖苷(11)。其中化合物2、4、6~11为该种首次分得。  相似文献   

6.
狗脊化学成分研究   总被引:9,自引:0,他引:9  
从狗脊(Woodwardia japonica(L.f.)Sm)中分离得到五个化合物,经解析,分别鉴定为:山柰素-3-O-α-L-(4-O-乙酰基)鼠李糖基-7-O-α-L-鼠李糖甙(kaempferol3-O-α-L-(4-O-acetyl)rhamnopyranoside-7-O-β-L-rhamnopyranoside)(Ⅰ),山柰素-3-O-α-L-鼠李糖基-7-O-α-L-鼠李糖甙(kaempferol3-O-α-L-rhamnopyranoside-7-O-α-L-rhamnopyanoside)(Ⅱ),狗脊蕨酸(woodwardinic acid)(Ⅲ),β-谷甾醇(β-sitosterol)(Ⅳ),胡萝卜甙(daucosterol)(Ⅴ),这五个化合物均系首次从该植物中获得。  相似文献   

7.
小叶石楠中苷类化学成分的研究   总被引:2,自引:2,他引:2  
从小叶石楠[Photinia parvifolia (Pritz.)Schneid]茎中分离得到10种化合物,利用波谱学方法分别鉴定为:(6′-O-palmitoly)-sitosterol-3-O-β-D-glucoside(1),isotachioside(2)、hexaacetate of (-)-lyoniresinol-3α-L-rhamnopyranoside(3a),koaburaside(4)、2,6-dimethoxy-4-hydroxyphenol-1-O-β-D-glucopyranoside(5),3-O-(β-D-glucopyranosyl)-1-(3′,5′-dimethoxy-4′-hydroxyphenyl)-1-propanone(6),di-O-methylcrenatin(7),L-threoguaiacylglycerol 8-O-β-glucopyranoside(8),苦杏仁苷(9),D-threo-guaiacylglycerol 8-O-β-glucopyranoside(10)。以上10个化合物均为首次从该属植物中分离得到。  相似文献   

8.
运用多种色谱手段分离纯化尾巨桉的化学成分,并通过波谱法对分离到的化合物进行结构鉴定。结果表明:从尾巨桉叶和根中分离并鉴定了5个化合物,分别为鞣花酸(ellagic acid,1)、3-O-甲基并没食子酸(3-O-methylellagic acid,2)、3,3′-O-二甲基鞣花酸(3,3′-di-O-methylellagic acid,3)、3-O-甲基鞣花酸4′-O-α-L-吡喃鼠李糖苷(3-O-methylellagic acid 4′-O-α-L-rhamnopyranoside,4)、反式对羟基肉桂酸((E )-p-hydroxy-cinnamic acid,5)。其中,化合物2~5为首次从该植物中分离得到。  相似文献   

9.
运用硅胶、Sephadex LH-20、ODS柱层析及半制备高效液相色谱技术对一引种虎眼万年青属植物Ornithogalum thyrsoides的化学成分进行研究,从其乙醇提取物的乙酸乙酯部分分离得到7个化合物.通过MS、NMR等波谱技术确定其结构分别为(23S,24S,25S)-23,24-dihydroxyruscogenin- 1-O-α-L-rhamnopyranosyl(1 →2)-α-L-arabinopyranoside(1),(24S,25S)-3β,24-dihydroxyspirost-5 -en- 1β-yl O-α -L-rhamnopyranosyl-(1→2)-α-L-arabinopyranoside(2),β-胡萝卜苷(3)β-谷甾醇(4),山奈酚-4′-O-β-D-吡喃葡萄糖苷(5),千层纸素A(6)和汉黄芩素(7).其中,化合物1、5~7为首次从该属植物中分离得到.体外药理活性结果显示这7个化合物对HCT-8、Bel-7402、BGC-823、A549及A2780实体瘤细胞株无明显细胞毒活性.  相似文献   

10.
小粒吴茱萸的化学成分研究   总被引:4,自引:0,他引:4  
从中药小粒吴茱萸(石虎)Evpdia rutaecarpa var.officinalis的近成熟果实中分离得到15个成分,分别为吴茱萸碱(evodiamine,1),吴茱萸次碱(rutaecarpine,2),羟基吴茱萸碱(hydroxyevodiamine,3),14-甲酰基二氢吴茱萸次碱(14-formyldihydrorutaecarpine,4),吴茱萸酰胺(evodiamide,5),吴茱萸酰胺-Ⅰ(goshuyuamide-Ⅰ,6),二氢吴茱萸新碱(dihydroevocarpine,7),茵芋碱(skimmianine,8),槲皮素-3-O-β-D-半乳糖甙(quercetin-3-O-β-D-galactoside,9),异鼠李素-3-O-β-D-半乳糖甙(isorhamnetin-3-O-β-D-galactoside,10);rutaevine(11);β-谷甾醇(β-sitosterol,12),胡萝卜甙(daucosterol,13);棕榈酸(palmaticacid,14),硬脂酸(stearicacid,15)。除了化合物1,2,3,7,11外,其余的10个化合物均是首次从该植物中得到。  相似文献   

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14.
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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16.
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   

17.
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   

18.
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   

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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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