排序方式: 共有42条查询结果,搜索用时 17 毫秒
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滇重楼地上部分的配糖体 总被引:13,自引:0,他引:13
从滇重楼ParispolyphyllaSm.var.yunnanensis(Fr.)H-M,地上部分,分离出4个微量的配糖体,经光谱分析和化学降解证明其化学结构分别为25S-异钮替皂甙元-3-O-α-L-鼠李吡喃糖基(1→2)[α-L-鼠李吡喃糖基(1→4)]-β-D-葡萄吡喃甙(A),26-β-D-葡萄吡喃糖基-纽替皂甙元-3-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),山奈酚-3-O-β-D-葡萄吡喃糖基(1→6)-β-D-葡萄吡喃甙(C),7-O-α-L-鼠李吡喃糖基-山奈酚-3-O-β-D-葡萄吡喃糖基(1→6)-β-D-葡萄糖甙(D)。 相似文献
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RNA介导的病毒抗性在转基因烟草中的遗传分析 总被引:7,自引:0,他引:7
以含非翻译马铃薯Y病毒外壳蛋白(PVY—MCP)基因的抗病和感病T0代转基因烟草为材料,对转基因及RNA介导的病毒抗性在T1~T4代转基因植株中的遗传进行了研究。结果表明,在含低拷贝(1~2个)转基因的感病植株后代中,转基因是作为一个单显性遗传位点,遵循孟德尔遗传分离规律,各世代转基因植株仍表现感病。含多拷贝(4~6个)转基因的抗病植株,转基因在T1代的分离虽符合多位点插入的15:1和63:1遗传规律,但转基因发生了重排,RNA介导的病毒抗性表现为不稳定遗传。从含多拷贝转基因的抗病植株的T1代株系中,分离获得了两株含2个拷贝转基因的抗病植株;其后代中,转基因及抗性遗传遵循孟德尔遗传分离规律,可稳定遗传和表达,获得纯合的抗病转基因株系。对转基因在不同抗病类型植株中整合方式分析显示,抗病植株中多存在转基因的反向串联重复序列。 相似文献
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滇重楼地上部分的两个微量皂甙 总被引:9,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
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来江藤的苯丙素类配糖体成分 总被引:3,自引:0,他引:3
从云南民间药用植物来江藤(Brandisia hancei Hook.f.)的全草中分离到10个化合物,分别鉴定为3,4-二羟基苯乙醇基-O-α-L-鼠李吡喃糖基(1→3)-β-D-(4-O-咖啡酰基)-半乳吡喃糖苷(1),3,4-二羟基苯乙醇基-O-α-L-鼠李吡喃糖基(1→3)-β-D-(2-O-乙酰基-4-O-咖啡酰基)-半乳吡喃糖苷(2),acteoside(3),2’-acetylacteoside(4),poliumoside(5),2’-acetylpohumoside(6),mussaenoside(7),luteolin-7-O-β-D-glucoside(8),luteolin(9)和mannitol(10)。化合物1-6为苯丙素配糖体成分,其中化合物2为新化合物,化合物1为首次从该属植物中获得。关键词:来江藤;苯丙素类配糖体;3,4-二羟基苯乙醇基-O-α-L-鼠李吡喃糖基(1→3)-β-D-(2-O-乙酰基-4-O-咖啡酰基)-半乳吡喃糖苷。 相似文献
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Seven compounds have been isolaed from the roots of Curculigo orchioides. On the basis of spectral analysis,their structures were elucidated as 2,6-dimethoxy benzoic acid (A),orcinol glucopyranoside(B),curculigine A(C),curculigoside(D),24s,3β,11α,16,24-tetrahyaroxycycloartenol-3-O-α-L-rhamnopyranosyl(1→2)-β-D-glucopyranoside(E),24s,3β,11a,16β,24-tetrahydroxycycloartenol-3-O-β-d-glucopyranosyl(1→2)-β-D-glucopyranoside(F) and dancosterol(G). Saponin F is a new tritepenoid compound. 相似文献
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Four new compounds, 3-(4-hydroxy-3,5-dimethoxyphenyl)propyl formate (1), 2,6-dimethoxy-4-[(1S)-3-methoxypropyl]phenol (2), (1R,2R)-4-[(3R)-3-hydroxybutyl]-3,3,5-trimethylcyclohex-4-ene-1,2-diol (3), and (1S,3R,3aR,6S,7S,9aR)-decahydro-1-(hydroxymethyl)-1,7-dimethyl-3a,7-methano-3aH-cyclopentacyclooctene (4) were isolated from the leaves of Acer truncatum, together with twelve known compounds. Their structures were elucidated on the basis of extensive spectroscopic techniques. The absolute configuration of compound 3 was established by the modified Mosher's method. All compounds were evaluated for antibacterial activities. 相似文献
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Five new steroids, including the four new steroidal saponins ypsilandroside B (1), ypsilandroside A (2), isoypsilandroside A (4), and isoypsilandroside B (5), as well as the new steroidal sapogenin isoypsilandrogenin (3), were isolated from the whole plant of Ypsilandra thibetica Franch. Their structures were determined on the basis of spectroscopic analyses, including extensive 2D-NMR techniques. The structure and relative configuration of ypsilandroside B (=(3beta,12alpha,25R)-3-[(alpha-L-rhamnopyranosyl-(1-->2)-beta-D-apiofuranosyl)oxy]spirost-5-ene-12,27-diol; 1) was unequivocally determined by single-crystal X-ray diffraction. The antifungal and antibacterial activities of 1-5 towards various types of fungi and bacteria are reported. 相似文献
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从无患子科无患子(Sapindus mukorossi Gaertn.)根中分离到两个新的大戟烷型三萜皂甙Sapimukoside A (1) 和Sapimukoside B (2).运用波谱和化学方法鉴定它们的结构为3-O-α-L-鼠李吡喃糖基-(1→2)-[α-L-阿拉伯吡喃糖基-(1→3)]-β-D-葡萄吡喃糖基-21, 23R-epoxyl tirucall-7, 24R-diene-3β, 21-diol (1) 和3-O-α-L-鼠李吡喃糖基-(1→6)-β-D-葡萄吡喃糖基21, 23R-epoxyl tirucall-7, 24R-diene-3β, 21-diol (2). 相似文献
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