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排序方式: 共有106条查询结果,搜索用时 31 毫秒
81.
Simmons MP Cappa JJ Archer RH Ford AJ Eichstedt D Clevinger CC 《Molecular phylogenetics and evolution》2008,48(2):745-757
The phylogeny of Celastraceae tribe Celastreae, which includes about 350 species of trees and shrubs in 15 genera, was inferred in a simultaneous analysis of morphological characters together with nuclear (ITS and 26S rDNA) and plastid (matK, trnL-F) genes. A strong correlation was found between the geography of the species sampled and their inferred relationships. Species of Maytenus and Gymnosporia from different regions were resolved as polyphyletic groups. Maytenus was resolved in three lineages (New World, African, and Austral-Pacific), while Gymnosporia was resolved in two lineages (New World and Old World). Putterlickia was resolved as nested within the Old World Gymnosporia. Catha edulis (qat, khat) was resolved as sister to the clade of Allocassine, Cassine, Lauridia, and Maurocenia. Gymnosporia cassinoides, which is reportedly chewed as a stimulant in the Canary Islands, was resolved as a derived member of Gymnosporia and is more closely related to Lydenburgia and Putterlickia than it is to Catha. Therefore, all eight of these genera are candidates for containing cathinone- and/or cathine-related alkaloids. 相似文献
82.
Stem bark of Hippocratea excelsa afforded six pentacyclic triterpenes, five oleanane and one ursane types. They were identified as 11beta,21beta-dihydroxy-olean-12-ene-3-one (2), 3alpha,11alpha,21beta-trihydroxy-olean-12-ene (3), 3alpha,21beta-dihydroxy-11alpha-methoxy-olean-12-ene (4), 3alpha,21beta-dihydroxy-olean-9(11),12-diene (5), 3alpha,21beta-dihydroxy-olean-12-ene (6) and 3alpha,21beta-dihydroxy-11alpha-methoxy-urs-12-ene, isolated as its diacetate derivative (7), as well as 3alpha,21beta-dihydroxy-olean-12-ene (1) previously isolated from the root bark. The known alpha- and beta-amyrin, oleanoic and ursolic acids, trans-polyisoprene, and the ubiquitous beta-sitosterol were also isolated. Structures were elucidated on the basis of spectroscopic analyses, including homo- and heteronuclear correlation NMR experiments (COSY, ROESY, HSQC and HMBC) and comparison with literature data. The antigiardial activity of compounds 2-5 was not significant. 相似文献
83.
福建假卫矛属(卫矛科)一新种——德化假卫矛 总被引:1,自引:0,他引:1
对新种德化假卫矛进行描述,该种仅见福建德化九仙山。 相似文献
84.
Bioassay‐guided phytochemical investigation of the stalks of Microtropis triflora Merr . & F.L. Freeman led to the isolation of ten triterpenes 1 – 10 , including one novel compound 3,24‐epoxy‐2α,24‐dihydroxyfriedelan‐29‐oic acid ( 1 ). Their chemical structures were identified on the basis of spectroscopic analysis, including HR‐ESI mass spectrometry, 1D‐ and 2D‐NMR (1H, 13C, 1H,1H‐COSY, HSQC, HMBC, and NOESY), and by comparison with the data reported. The cytotoxicities of compounds 1 – 10 against a panel of cultured human tumor cell lines (Bcap37, SMMC7721, HeLa, CNE) were evaluated. The new compound 1 showed moderate anti‐tumor activities with IC50 values of 39.22, 29.24, 23.28, and 68.81 μm /ml, respectively. These results might be helpful for explaining the use of M. triflora in traditional medicine. Triterpenes are characteristic of Microtropis genus and could be useful as potential chemotaxonomic markers. 相似文献
85.
Insecticidal sesquiterpene pyridine alkaloids from Euonymus species 总被引:11,自引:0,他引:11
Three insecticidal sesquiterpene pyridine alkaloids with a beta-dihydroagarofuran sesquiterpene skeleton, euoverrine A (1), B (2), and euophelline (3), and a known compound, euojaponine C (4), were isolated from the root bark of Euonymus verrucosides, E. fortunei and E. phellomana by bioassay-guided fractionation. Their chemical structures were elucidated mainly by analyses NMR and MS spectral data. 相似文献
86.
在开展南蛇藤属分类修订的过程中,于 2011 年在中国云南省西双版纳傣族自治州勐腊县发现南蛇藤属中国分布新记录——拟独子藤 ( Celastrus monospermoides) 。该种形态与独子藤 ( C. monospermus) 较为相似,主要区别为前者叶片窄椭圆形,先端渐尖,果实成熟后不具雌蕊柄,种子长12 mm 以内; 后者叶片椭圆形、阔椭圆形至倒卵椭圆形,果实具有明显的雌蕊柄,种子长15 mm 以上。分子系统学研究表明,拟独子藤与独子藤处于不同分支中,与青江藤 ( C. hindsii) 系统关系最近。由于原记录仅分布于印度尼西亚、马来西亚和菲律宾等热带地区,因此在原产地和我国云南省之间的地区应有更多居群分布,这为探讨南蛇藤属的起源和扩散提供了线索。 相似文献
87.
88.
A comparative anatomical study on the secondary phloem of 5-genera, 10 species in Celastraceae was carried out. Based on the phloem structure characters, 3 phloem types were observed. In type Ⅰ , as seen in 5 species of Euonymus, the sieve-tube elements have more inclined end walls and numerous sieve areas (compound sieve plates), phloem rays are almost uniseriate. Type Ⅱ is seen in Celastrus and Tripterygium. It has relatively short sievetube elements, slight inclined end wall and sparse number of sieve areas: the phloem fiber is not lignified and ray is multiseriate. Type Ⅲ is observed in Dipentodon and Perrottetia, the sieve-tube elements are with simple sieve plate, the end wall is almost transverse, there are sclereid and fiber groups in the nonfounctional phloem, and phloem rays are uniseriate or biseriate. 相似文献
89.
《Phytochemistry》2013
Celastrus paniculatus is a traditional medicinal plant with diverse pharmacological activities. To identify its bioactive constituents, three new β-dihydroagarofuranoid sesquiterpenes were isolated from the whole plant, of which the major constituent is (1α,2α,8β,9β)-1,8-bis(acetyloxy)-2,9-bis(benzoyloxy)-14-hydroxy-β-dihydroagarofuran. It was assessed for its antiproliferative activity, and it suppressed the viability of MCF-7 breast cancer cells with an IC50 of 17 ± 1 μM. This growth inhibition was, in part, attributable to apoptosis. Moreover, this drug treatment led to LC3B-II accumulation, indicative of autophagy. Western blot analysis established its ability to target a broad range of signaling effectors related to survival and cell cycle progression, including Akt, NF-κB, p53, and MAP kinases. In addition, flow cytometry analysis indicates increased reactive oxygen species production in response to this compound. Taken together, these findings suggest a pleiotropic mode of mechanism that underlies the antiproliferative activity of this compound in MCF-7 breast cancer cells. 相似文献
90.
《Phytochemistry》2013
Twenty-one triterpenes consisting of a lupane derivative, two friedelanes, an oleanane derivative, and 17 ursane-type triterpenoids, together with three known triterpenes, three sterols, a fatty acid, a sesquiterpene alkaloid, and a glycerol derivative, were isolated from the stem of Siphonodon celastrineus. Their structures were characterized by various spectroscopic techniques, as well as comparison with literature data. Twenty-seven metabolites of these were evaluated for cytotoxic activity against six human cancer cell lines. The biosynthetic formation of a 1,4-dioxane bridge is also discussed. 相似文献