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1.
首次从中国特有的单属单种植物羽叶点地梅(Pomatosace filicula Maxim.)分离到13个化合物.应用波谱技术(尤其是2D-NMR:TOCSY,HMQC,HMBC)及化学方法鉴定了它们的结构.其中,化合物3为一新的三萜皂苷类化合物,其结构为13β,28-epoxy-16-oleananone-3-O-[α-L-rhamnopyranosyl-(1→6)-O-β-D-glucopyranosyl-(1→4)-O-β-D-glucopyranosyl-(1→6)-O-β-D-glucopyranosyl-(1→2)]-β-D-glucopyranoside,命名为羽叶点地梅甲苷(pomatoside A).  相似文献   

2.
从铁破锣(Beesia calthaefolia(Maxim.)Ulbr.根茎中分离得到5个化合物(1-5),经化学和波谱学方法鉴定,其中2个为有机酸-铁破锣酸(beesic acid,9-phenyl-2E,4E,6E,8E-nontetraenoic acid,1)和香草酸(2);3个为齐墩果酸型三萜皂甙:oleanolic acid-3-o-α-Larabinopyranosyl--28-O-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester(3),hederasaponin B(oleanolic acid-3-O-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosly-28-Oα-L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester,4)和铁破锣皂甙Q(beesioside Q,oleanolic acid-3-O-β-D-glucopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranolsyl-28-O-α-L-rhamnopyranosyl-(1→4)-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester,5)。化合物1系首次从自然界中分离得到,化合物5为新化合物。  相似文献   

3.
金铁锁的新三萜皂甙   总被引:10,自引:0,他引:10  
从金铁锁(Psammosilene tunicoides W.C.Wu et C.Y.Wu)根部分离得到5个齐墩果烷型五环三萜皂苷,它们的结构通过波谱和化学方法分别鉴定为:3-O-β-D-galactopyranosyl-(1→2)-β-D-glucuronopyranosyl-gypsogenin(1),3-O-β-D-galactopyranosyl-(1→2)-[β-D-galactopyranosyl-(1→3)-β-D-glucuronopyranosyl-gypsogenin(2),3-O-β-D-galactopyranosyl-(1→2)-β-D-glucuronopyra-nosyl-gypsogenin-28-O-β-D-xylopyranosyl-(1→4)-[β-D-glucopyranosyl-(1→3)]-α-L-rhamnopyranosyl(1→2)-β-D-fucopyranoside(LobatosideI,3),3-O-β-D-galactopyranosyl-(1→2)-[β-D-xylopyranosyl-(1→3)-β-D-glucuronopyranosylgypsogenin-28-O-β-D-xylopyranosyl-(1→4)-[β-D-glucopyranosyl-(1→3)]-α-L-rhamnopyranosyl(1→2)-β-D-fucopyranoside(4),3-O-β-D-galactopyranosyl-(1→)-β-D-glucuro-nopyranosyl-grpsogenin-28-O-β-D-xylopyranosyl-(1→4)-[β-D-6-O-acetylglucopyranosyl-(1→3)-β-D-glucuro-nopyranosyl-gypsogenin-28-O-β-D-xylopyranosyl-(1→4)-[β-D-6-O-acetylglucopyranosyl-(1→3)]-α-L-rh-amnopyranosyl(1→2)-β-D-fucopyranoside(5),其中5为新化合物,1和2为首次从自然界中分离得到。  相似文献   

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前期研究发现seco-pregnane类甾体苷具有较强的抗烟草花叶病毒(TMV)活性,为进一步寻找活性化学成分,开展白薇化学成分研究。从白薇乙醇提取物的氯仿部位中分离得到10个单体化合物,根据其理化性质以及波谱数据鉴定为:glaucogenin-C 3-O-α-L-diginopyranosyl-(1→4)-β-D-thevetopyranoside(1)、glaucogenin-C 3-O-β-D-oleandropyranosyl-(1→4)-β-D-digitoxopyranosyl-(1→4)-α-L-cymaropyranoside(2)、glaucogenin-C 3-O-β-D-glucopyranosyl-(1→4)-β-D-glucopyranosyl-(1→4)-β-D-oleandropyranoside(3)、glaucogenin-A 3-O-α-L-cymaropyranosyl-(1→4)-β-D-digitoxopyranosyl-(1→4)-β-D-oleandropyranoside(4)、glaucogenin-A 3-O-α-L-diginopyranosyl-(1→4)-β-D-cymaropyranosyl-(1→4)-β-D-oleandropyranoside(5)、glaucogenin-A 3-O-α-L-cymaropyranosyl-(1→4)-α-L-cymaropyranosyl-(1→4)-β-D-oleandropyranoside(6)、glaucogenin-A 3-O-α-L-cymaropyranosyl-(1→4)-β-L-cymaropyranosyl-(1→4)-β-L-cymaropyranoside(7)、glaucogenin-A 3-O-α-L-cymaropyranosyl-(1→4)-β-D-cymaropyranosyl-(1→4)-β-L-cymaropyranoside(8)、antofine(9)、2-O-β-D-fructofuranosyl-β-D-glucopyranoside(10)。化合物1~8,10均为首次从该植物中分离得到。采用半叶枯斑法,从钝化活性、保护活性、治疗活性三方面评估化合物1~9的生物活性,结果表明,化合物1和9具有显著的抗TMV活性。  相似文献   

5.
从著名藏药白花刺参(Morina nepalensis var.alba Hand.-Mazz.)的水溶性部分分离到2个新三萜皂甙--刺参甙K(1)和刺参甙L(2),以及一个已知三萜皂甙mazusaponin I(3).应用波谱和化学方法,刺参甙K和刺参甙L的结构分别鉴定为3-O-α-L-arabinopyranosyl-(1→3)-β-D-xylopyranosyl siaresinolic acid(1)和3-O-β-D-glucopyranosyl-(1→3)-α-L-arabinopyranosyl siaresinolic acid 28-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranoside(2).  相似文献   

6.
从著名藏药白花刺参(Morina nepalensis var.alba Hand.-Mazz)的水溶性部分分离到2个新三萜皂甙-刺参甙K(1)和刺参甙L(2),以及一个已知三萜皂甙mazusaponinⅠ(3)。应用波谱和化学方法,刺参甙K和刺参甙L的结构分别鉴定为3-O-α-L-arabinopyranosyl-(1→)-β-D-xylopyranosyl siaresinolic acid(1)和3-O-β-D-glucopyranosyl-(1→3)-α-L-arabinopyranosyl siaresinolic acid28-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranoside(2)。  相似文献   

7.
从思茅藤(Epigynum auritum (schneid.)Tsiang et P.T.Li)的茎皮中分离到一个新的化合物,命名为思茅藤甙(Epigcoside)Ⅰ和已知化合物Ⅱ。通过光谱分析和化学反应证明,其结构为Ⅰ(+)—儿茶素-3-O-α-D-葡萄吡喃糖(1→6)-β-D葡萄吡喃糖甙((+)-catchin—3-O-α-D-glucopyranosyl-(1→6)-β—D-glucopyranoside;Ⅱβ-谷甾醇β-D-葡萄糖甙(β-sitosterol-β-D-glucoside)。  相似文献   

8.
Two New Saponins from Lysimachia capillipes Hemsl.   总被引:1,自引:0,他引:1  
To investigate the saponins from whole plants of Lysimachia capillipes Hemsl., two new saponins, named capilliposide E (1) and capilliposide F (2), were isolated. The structures of the new sa ponins were elucidated as 3 β, 22α-dihydroxy- 16α-acetat-28→ 13 -lactone-oleanane-3 -O- [β-D-glucopyranosyl(1→2)-α-L-arabinpyranoyl]-22-O-β-D-glucopyranoside (1) and 3 β, 22α-dihydroxy- 16α-acetat-28→ 13-1actone-oleanane-3-O- { [β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-(1→4)]-α-L-arabinpyranoyl }-22-O-βD-glucopyranoside (2). The structures of these compounds were determined by 1D- and 2D-NMR, MS techniques, and chemical methods.  相似文献   

9.
从中药知母(Anemarrhena asphodeloides Bge.)的70%乙醇提取物中分离得到6个化合物,经波谱学方法和与已知样品对照鉴定为:3-O-β-D-glucopyranosyl-(1→2)-β-D-galactopyranosyl-(3β,5β)-pregn-16(17)-ene-20-one(1)、timosaponin AIII(2)、timosaponin BIII(3)、22-hydroxy-5β-furost-3β,15α-diol-3-O-β-D-glucopyranosyl(1→2)-β-D-galactopyranoside(4)、timosaponin G(5)、β-daucosterol(6)。其中化合物1为新天然产物,命名为知母孕甾A,是知母中首次发现的C21甾体类化合物,经HR ESI-MS、1D NMR、2D NMR确定其结构,并首次对其核磁数据进行归属。  相似文献   

10.
从云南匙羹藤(Gymnema yunnaflense Tsiang)中分离得到2个新C_(21)甾体甙,命名为云南匙羹藤甙A(Ⅰ)和B(Ⅱ)(gymnemaroside A, B)。据化学反应和光谱数据,推定其结构分别为:本波甙元3-氧-β-D-葡萄糖吡喃基-(1→4)-3-氧-甲基-6-去氧-β-D阿洛糖吡喃基-(1→4)-β-D-加拿大麻糖吡喃基-(1→4)-β-D-加拿大麻糖吡喃甙〔penupogenin 3-O-β-D-glucopyranosyl-(1→4)-3-O-methyl-6-deoxy-β-D-allopyranosyl-(1→4)-β-D-cymaropyranosyl-(1→4)-β-D-cymaropyranoside〕和吉马甙元3-氧-β-D-葡萄糖吡喃基-(1→4)-3-氧-甲基-6-去氧-β-D-阿洛糖吡喃基-(1→4)-β-D-加拿大麻糖吡喃基-(1→4)-β-D-加拿大麻糖吡喃甙〔symnemarsgenm 3-O-β-D-glucopyranosyl-(1→4)-3-O-methyl-6-deoxy-β-D-allopyranosyl-(1→4)-β-D-cymaropyranosyl-(1→d)-β-D-cymaropyranoside〕。  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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正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases  相似文献   

16.
Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.  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   

20.
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   

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