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1.
唐古特白刺叶黄酮类及酚酸类成分的分离鉴定   总被引:13,自引:0,他引:13  
从蒺藜科植物唐古特白刺(NitrariatangutorumBor.)叶中分得8个黄酮类及酚酸类化合物,经理化常数测定和波谱学方法确定了它们的化学结构,分别为:3甲氧基4羟基反式桂皮酸(1)、对羟基反式肉桂酸(2)、3羟基4甲氧基苯甲酸(3)、邻羟基苯甲酸(4)、3,5二甲醚山柰黄素7OβD葡萄糖甙(5)、3甲醚山柰黄素7OβD葡萄糖甙(6)、异鼠李素7OβD葡萄糖甙(7)、异鼠李素3OβD芸香糖甙(8)。以上化合物均为首次从该植物中得到,可以作为白刺属化学分类学的特征性化合物。  相似文献   

2.
细锥香茶菜化学成分的研究   总被引:3,自引:0,他引:3  
从细锥香茶菜(Rabdosiacoetsa(Buch.Ham.exD.Don)Hara)的叶中分离到9个化合物,通过波谱分析阐明其结构,其中1个为新的二萜酸———7α,12α,14β三羟基15酮对映贝壳杉18羧酸,命名为细锥香茶菜酸(coetsanoicacid)。另外8个化合物分别为二氢昆明香茶菜丙素、昆明香茶菜丙素、白柔毛香茶菜甲素、大萼香茶菜丙素、4羟基Δ8,9(Z)鞘氨醇2′羟基正二十(二十一二十六)碳酸酰胺、乌苏酸、2α,3β二羟基乌苏酸和胡萝卜甙。神经酰胺类化合物系首次从该属植物中分离得到。  相似文献   

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从民间药用抗肝炎药相思子(AbrusprecatoriusL.)根中分得8个异黄烷醌类化合物,即相思子醌A、B、D、E、F、G以及已知化合物3,7二羟基6甲氧基双氢黄酮和2,8二羟基3,4,9,10四甲氧基紫檀素。用化学转化和光谱学方法包括1H1HCOSY、1H13CCOSY、CD等方法鉴定它们的结构。  相似文献   

4.
从单条草(LysimachiacandidaLindl)全草中分离出3个皂甙类化合物,经波谱分析并结合化学方法鉴定为:报春花素A3OβD吡喃木糖基(1→2)βD吡喃葡萄糖基(1→4)[βD吡喃葡萄糖基(1→2)]αL吡喃阿拉伯糖甙(1)、原报春花素A3OβD吡喃木糖基(1→2)βD吡喃葡萄糖基(1→4)[βD吡喃葡萄糖基(1→2)]αL吡喃阿拉伯糖甙(lysikoianoside,2)和α菠甾醇葡萄糖甙(3)。其中1是新化合物,命名为单条草甙(candidoside)。  相似文献   

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柴胡皂甙s的结构鉴定   总被引:4,自引:0,他引:4  
从南柴胡(BupleurumscorzonerifoliumWild.)根中分得5个三萜皂甙。根据理化性质和波谱数据,鉴定其中新皂甙为3β,16α,23,28四羟基齐墩果烷11,13(18)二烯3OβD吡喃葡萄糖基(1→6)[αL吡喃鼠李糖基(1→4)]βD吡喃葡萄糖甙,命名为柴胡皂甙s(saikosaponins)。另4个皂甙分别为柴胡皂甙a、c、b1、b2。  相似文献   

6.
朝鲜淫羊藿的化学成分(Ⅱ)   总被引:3,自引:1,他引:2  
从朝鲜淫羊藿的地上部分分离到七个成分(Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ、Ⅵ、Ⅶ)。经UV,IR,^1H-NMR,^13C-NMR,MS及化学方法鉴定了它们的结构,分别是icaritin-3-O-a-L-rhamnopyranoside(Ⅰ),sagittatoside A(Ⅱ),sagittatoside B(Ⅲ),3,5,7-trihydroxyl-4^1-methoxy1-8-preny1-flavone-  相似文献   

7.
圆穗蓼中的新黄酮甙成分   总被引:1,自引:0,他引:1  
从圆穗蓼(Polygonum sphaerostachyum Meisn.)中分离得到2个新黄酮甙,经光谱分析和化学方法鉴定为:3'-羟基-5,4'-二甲氧基-6,7-二氧亚甲基黄酮-3-O-「β-D-吡喃木糖基(1→6)」-β-D-吡喃葡萄糖甙⑴和5,4'-二甲氧基-3'-异丙烯基乙酰基-6,7-二氧亚甲基黄酮-3-O-「β-D-吡喃木糖基(1→6)-β-D-吡喃葡萄糖甙⑵,分别命名为圆穗蓼素A  相似文献   

8.
石香薷中化学成分的研究   总被引:13,自引:0,他引:13  
从石香薷(Mosla chinensis Maxim .)中分离到10 个化合物,经光谱分析、化学方法及与已知化合物对照,分别鉴定为:6-甲基三十三烷(1)、β-谷甾醇(2)、熊果酸(3)、5-羟基-6,7-二甲氧基黄酮(4)、5-羟基-6-甲基-7-O-β-D-吡喃木糖(3→1)-β-D-吡喃木糖双氢黄酮甙(5)、5,7-二羟基-4-甲氧基黄酮(6)、洋芹素(7)、山奈素-3-O-β-D-葡萄糖甙(8)、桑色素-7-O-β-D-葡萄糖甙(9)、鼠李柠檬素-3-O-β-D-芹糖(1→5)芹糖-4-O-β-D-葡萄糖甙(10)。其中,化合物5和10 为新化合物  相似文献   

9.
滇重楼地上部分的两个微量皂甙   总被引:10,自引:1,他引:9  
从滇重楼地上部分中分离出两个新的微量的甾体皂甙PolyphyllosideⅢ和Ⅳ,根据化学降解和光谱分析,它们的化学结构分别为27-羟基-偏诺皂皂甙元-3-O[a-L-鼠李吡喃糖基(1→2)][a-L-鼠李吡喃糖基(1→4-a-L鼠李吡喃糖基(1→4)]-β-D-葡萄吡喃糖甙,23β,27-二羟基-偏皂甙元-3-O-[a-鼠李吡喃糖(1→2)]  相似文献   

10.
香豆素的^1H—NMR检测及其在阿魏亚族化学分类中的应用   总被引:2,自引:0,他引:2  
利用1HNMR法检测中国阿魏亚族(FerulineaeDrude)8属27种3变种根部乙醚提取物的香豆素成分类型,其中主要为线型二氢呋喃型香豆素(Ⅰ)和角型二氢吡喃型香豆素(Ⅳ),线型二氢吡喃型香豆素(Ⅲ)和角型二氢呋喃型香豆素(Ⅱ)较少。据此,将8属分成4类:(1)阿魏属(FerulaL.)、球根阿魏属(SchumanniaKuntze)、簇花芹属(SoranthusLedeb.)和伊犁芹属(TalasiaKorov.)未测出(不含)香豆素;(2)弓翅芹属(ArcuatopterusShehetShan)和川明参属(ChuanminshenShehetShan)含Ⅰ类;(3)胀果芹属(PhlojodicarpusTurcz.exBes.)含Ⅳ类;(4)前胡属(PeucedanumL.)含Ⅰ类和Ⅳ类。上述结果支持将球根阿魏、簇花芹和伊犁芹3个属并入阿魏属,另3个寡种属与前胡属关系最密切。所分析的前胡属17种2变种可分成5组,其中不含香豆素的剌尖前胡和含Ⅲ类香豆素的紫花前胡及其变种最特殊,支持将它们分出前胡属的处理。  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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