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1.
屏边三七根茎中的两个新的齐墩果酸皂甙   总被引:9,自引:0,他引:9  
从屏边三七(Panax stipuleanatus Tsai et Feng)根茎中分离到二个齐墩果烷型新皂甙,命名为屏边三七甙(stipuleanoside)R_1和R_2,其化学结构经光谱分析和化学降解反应,分别确定为齐墩果酸-3-O-β-D-葡萄吡喃糖基(1→3)[α-L-阿拉伯呋喃糖基(1→4)]-β-D-葡萄吡喃糖醛酸甙(1)和齐墩果酸[28-O-β-D-葡萄吡喃糖基]-3-O-β-D-葡萄吡喃糖基(1→3)[α-L-阿拉伯呋喃糖基(1→4)]-β-D-葡萄吡喃糖醛酸甙(3)。  相似文献   

2.
从重楼属植物五指莲Paris axialis H.Li.根茎中分离到三个甾体皂甙,经化学降解,质谱,核磁共振谱分析,证明其中两个甙为新的化合物,即偏诺皂甙元-3-O-β-D-葡萄吡喃糖基(1→3)[α-L-鼠李吡喃糖基(1→2)]-β-D-葡萄吡喃糖甙(Ⅰ)和24α-羟基偏诺皂甙元-3-O-β-D-葡萄吡喃糖基(1→3)][α-L-鼠李吡喃糖基(1→2)]-β-D-葡萄吡喃糖(Ⅲ);另一个鉴定为薯芋皂甙元-3-O-β-D-葡萄吡喃糖基(1→3)[α-L-鼠李吡喃糖基(1→2)]-β-D-葡萄吡喃糖甙(Ⅱ)。  相似文献   

3.
小花棘豆化学成分的研究   总被引:6,自引:0,他引:6  
从有毒植物小花棘豆(Oxytropis glabra DC.)的地上部分分离得到10种化合物,经光谱分析及理化常数测定,分别鉴定为槲皮素(Ⅰ)、山奈酚(Ⅱ)、3′,7-二羟基-2′,4′-二甲氧基-异黄烷(Ⅲ)、山奈-7-O-α-L-鼠李吡喃糖甙(Ⅳ)、山奈酚-3-O-β-D-葡萄吡喃糖甙(Ⅴ)、山奈酚--O-β-D-葡萄吡喃糖(1→2)-β-D-葡萄吡喃糖甙(Ⅵ)、山奈酚-3-O-β-D-葡萄吡喃糖-7-O-β-D-葡萄吡喃糖甙(Ⅶ)槲皮素-3-O-β-D-葡萄吡喃糖甙(Ⅷ)、杨梅树皮甙(Ⅺ)和3-O-[α-L-鼠李吡喃糖基(1→3)-β-D-葡萄吡喃糖基(1→6)-β-D-葡萄吡喃糖醛酸基]-黄豆醇B(Ⅹ)。上述成分均为首次从该植物中分得。化合物Ⅹ为新化合物。  相似文献   

4.
从无柄新乌檀乙醇浸膏的正丁醇部位分离得到7个已知配糖体化合物,经波谱分析为:喹诺酸-3-O-β-D-葡萄吡喃糖基(28→1)-β-D-葡萄吡喃糖酯(1),齐墩果酸-(28→1)-β-D-葡萄吡喃糖酯(2),熊果酸-(28→1)-β-D-葡萄吡喃糖酯(3),喹诺酸-3-O-β-D-葡萄吡喃糖基-(1→3)-6-去氧-β-葡萄吡喃糖苷(4),齐墩果酸-3-O-β-D-吡喃木糖基-(1→2)-β-D-葡萄吡喃糖基-28-O-β-D-葡萄吡喃糖酯(5),番木鳖甙(6),7-甲氧基-龙胆苦甙(7)。这些化合物均为首次从该属中分离得到。  相似文献   

5.
盾叶薯蓣地上部分的三个新甾体皂甙   总被引:11,自引:0,他引:11  
从盾叶薯蓣Dioscorea zingiberensis Wright地上部分分离鉴定了四个甾体皂甙,经鉴定甙A为约莫皂甙元-3-O-[α-L-鼠李吡喃糖基(1→2)]-β-D-葡萄吡喃糖甙;甙B为24α-羟基约莫皂甙元-3-O-[α-L-鼠李吡喃糖基(1→2)]β-D-葡萄吡喃糖甙;甙C为约莫皂甙元-3-O-[α-L-鼠李吡喃糖基(1→2)][β-D-葡萄吡喃糖基(1→4)]-β-D-葡萄吡喃糖基;甙D为约莫皂甙元-3-O-[α-L-鼠李吡喃糖基(1→2)][β-D-葡萄吡喃糖基(1→3)]-β-D-葡萄吡喃糖甙。前三者为新化合物,分别命名为盾叶皂甙A_1、A_2、A_3(zingiberoside A_1、A_2、A_3),其中盾叶皂甙A_2的甙元为一新甾体皂甙元,命名为盾叶皂甙元(zingiberogenin)。  相似文献   

6.
枸骨的化学成分   总被引:8,自引:1,他引:7  
从枸骨(Ilex cornuta Lindl,ex paxt.)中分离得到20个化合物,鉴定了16个,分别为:枸骨甙1(Gougusidel,V)即坡摸酸3-β-O-O-L吡喃阿拉伯糖甙;枸骨甙2(Gouguside 2,Ⅵ)即3-β-O-D-吡喃葡萄糖基坡摸酸-β-28-O-D吡喃葡萄糖酯;枸骨甙3(Gouguside 3,Ⅶ)即3-β-O-(β-D-吡喃葡萄糖基)-α-L吡喃葡萄糖基坡摸酸-β-28-O-D-吡喃葡萄糖酯的类似物;枸骨甙4(Gouguside 5,ⅩⅦ)即3-β-O-(β-D-吡喃葡萄糖基)-α-L-吡喃葡萄糖基坡摸酸-β-28-O-D-吡喃葡萄糖酯;枸骨甙5(Gouguside 5,ⅩⅧ)即坡摸酸3-β-O-α-L-2’-乙酰氧基吡喃阿拉伯糖基-28-O-β-D-吡喃葡萄糖酯,枸骨甙6(Gouguside 6,ⅩⅪ)即3-β-O-(β-D-吡喃葡萄糖基)-α-L-4-乙酰氧基吡喃阿拉伯糖基坡摸酸-β-28-O-D-吡喃葡萄糖酯;枸骨甙7(Gouguside 7,ⅩⅩ)即3-β-O-α-L-吡喃阿拉伯糖基-28-O-β-D-吡喃葡萄糖酯;胡萝卜甙(daucostorol Ⅷ);2,4-二羟基苯甲酸(2,4-dihydroxybenzoicacid I);3,4-二羟基桂皮酸(3,4-dihyroxycinnamunic acid Ⅱ,Ⅳ);长链脂肪酸或醇5个(Longchain fatty acid Ⅲ,Ⅵ,Ⅶ,Ⅷ,ⅩⅣ)。在鉴定的16个化合物中,枸骨甙1、枸骨甙2、枸骨甙6和枸骨甙7为首次从枸骨中分离得到,枸骨甙3和枸骨甙4为新化合物。  相似文献   

7.
滇重楼地上部分的甾体皂甙   总被引:24,自引:3,他引:24  
从滇重楼Paris polyphylla Sm. var. yunnanensis (Fr.) H-M.地上部分分离得到3个甾体皂甙,经光谱测定和化学降解证明其化学结构分别为:偏诺皂甙元3O-α-L-鼠李吡喃糖基(1→2)〔α-L-鼠李吡喃糖基(1→4))-β-D-葡萄吡喃糖甙(A);孕甾-5,16-二烯-3β-醇-20-酮,3β-O-α-L-鼠李吡喃糖基(1→2)〔α-L-鼠李吡喃糖基(1→4)〕-β-D-葡萄吡喃糖甙(B);孕甾-5,16-二烯-3β-醇-20-酮,3β-O-α-L-鼠李吡喃糖基(1→2)〔α-L-鼠李吡喃糖基(1→4)-α-L-鼠李吡喃糖基(1→4)〕-β-D-葡萄吡喃糖甙(C)。甙A、B和C在滇重楼根中尚未发现,甙C系首次从重楼属植物中获得,而甙A具有止血的活性。  相似文献   

8.
茉莉花的化学成分   总被引:19,自引:0,他引:19  
从药用植物茉莉花(Jasminum sambac(L.)Ait.)花蕾中分离到9个化合物,通过波谱分析并与已知化合物数据对照,分别鉴定为:苄基-O-β-D-葡萄吡喃糖甙(1),苄基-O-β-D-木吡喃糖基(1→6)-β-D-葡萄吡喃糖甙(2),tetraol(3),molihuaoside D(4),sarnhcoside A(5),sambacoside E(6),芦丁(rutin)(7),山奈酚-3-O-α-L鼠李吡喃糖基(1-2)[α-L鼠李吡喃糖基(1-6)]-β-D半乳吡喃糖甙(8),斛皮素-3-O-α-L鼠李吡喃糖基(1→2)[α-L鼠李吡喃糖基(1→6)]-β-D-半乳吡喃糖甙(9)。  相似文献   

9.
油菜蜂花粉煮沸灭酶,减压蒸干,用80%乙醇提取,经AB-8大孔树脂、MCI柱和ODS反相柱层析柱分离,得到4个皂苷类化合物,通过理化方法、1H NMR、13C NMR等手段鉴定他们的化学结构,分别为:3,22-二羟基,3-O-β-D-葡萄糖-齐墩果烷(1)、3,22-二羟基,3-O-β-D-吡喃葡萄糖基(1→2)-β-D-吡喃葡萄糖基-[-β-D-吡喃葡萄糖(1→6)]-齐墩果烷(2)、3,22-二羟基,3-O-β-D-吡喃葡萄糖基(1→2)-β-D-吡喃葡萄糖基-[-β-D-吡喃葡萄糖(1→6)]-齐墩果酸(3)和3-O-β-D-葡萄糖-谷甾醇苷(4)。其中,皂苷1~3在油菜蜂花粉中首次报导。  相似文献   

10.
风轮菜中一个新皂苷类化合物的结构鉴定   总被引:1,自引:1,他引:0  
从风轮菜全草乙醇提取物的正丁醇萃取部分分离得到一皂苷类新化合物,通过谱学方法确定其结构为3β,16β,23,28-四羟基-11(12)-烯-齐墩果烷-3-O-[β-D-吡喃葡萄糖基(1→2)]-[β-D-吡喃葡萄糖基(1→3)]-β-D-吡喃夫糖苷(1),命名为风轮菜皂苷H.  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   

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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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