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从胡椒科植物山蒟中分得两个新木脂素类成分(Ia)和(Ⅱ),以及巴豆环氧素(Crorepoxide)(Ⅲ)和β-谷甾醇(Ⅳ)。经光谱分析及化学鉴定,(Ia)、(Ⅱ)为新结构,分别命名为山蒟素 B(hancinone)、山蒟素 C(hancinone C)。  相似文献   
2.
Self‐pollination has been hypothesized to be beneficial in environments where pollinators are rare as it can provide reproductive assurance. This study presents evidence for an autonomous self‐fertilization mechanism in the winter flowering plant, Brandisia hancei. To determine changes in the spatial separation of stigma and anthers, the length of style and stamens was recorded. Additionally, pollination treatments were carried out to test fruit‐set and seed production. Brandisia hancei is herkogamic in the early flowering stages. However, different growth rates of the filament and style lead to contact of stigma and anthers in the later stages, thereby facilitating self‐pollination. The highest seeds number is produced under an out‐crossing scenario but plants produce a considerable number of seeds even when purely selfed. Although pollinators are scarce, autonomous selfing alleviates the pollen limitation in B. hancei. Self‐fertilization in B. hancei seems to be an adaptive strategy to ensure reproduction when pollinators are scarce.  相似文献   
3.
来江藤的苯丙素类配糖体成分   总被引:3,自引:3,他引:0  
从云南民间药用植物来江藤(Brandisia hancei Hook. f.)的全草中分离到3个苯丙素配糖体成分,分别鉴定为2′-acetylacteoside,acteoslde和poliumoside,同时还分离到大量的甘露醇和卫茅醇。  相似文献   
4.
In our continuing search for novel antiangiogenic agents, a new lignan glycoside, (7R,8R)-1-(4-O-β-d-glucopyranosyl-3-methoxyphenyl)-2-{2-methoxy-4-[1-(E)-propene-3-ol]-phenoxyl}-propane-1,3-diol (1), along with three known lignans (24), were isolated from the 80% EtOH extract of Brandisia hancei stems and leaves. These isolates (14) were subjected to an in vitro bioassay to evaluate their effects on vascular endothelial growth factor (VEGF)-induced vascular permeability and migration of human retinal endothelial cells (HRECs). Of the compounds tested, compound 1 resulted in the greatest reduction in VEGF-induced vascular permeability by about 31.5% at 10 μM compared to the VEGF-treated control. In the migration assay, compounds 1 and 2 significantly decreased VEGF-induced HREC migration. Furthermore, zebrafish embryos treated with compounds 1 and 2 showed mild reductions of dorsal longitudinal anastomotic vessel (DLAV) formation.  相似文献   
5.
In continuation with our work on the neolignans of Piper hancei, two new neolignans, hancinone B (Ⅰa) and hancinone C (Ⅱ), with a known compound, crotepoxide, were isolated. The structures of la and Ⅱ have been identified by spectroscopic and chemical analysis.  相似文献   
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