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21.
Five new β‐carboline‐type alkaloids, dichotomines F–J ( 1 – 5 , resp.), along with nine known compounds, dichotomides I, III, V, and VII ( 6 – 9 , resp.), stellarines A and C ( 10 – 11 , resp.), dichotomine B ( 12 ), glucodichotomine B ( 13 ), and 1‐acetyl‐3‐carboxy‐β‐carboline ( 14 ), were isolated from the roots of Chinese medicinal plant Stellaria dichotoma L. var. lanceolata. Their structures were determined by chemical and spectroscopic means. Compounds 12 and 13 exhibited moderate cytotoxicity.  相似文献   
22.
ErvalanIiaYunnanensiSTsianghasbeenusedasafolkmedicineinChinaforthetreatmentofhypertensi0n'.Aspart0fourc0ntinuingpr0gramonthestudyofplant-derivedbioactivecomp0unds,thechemicaIconstituents0fE.yunnanensI1vgrowinginYunnanwereinvestigated.Intheprevi0uspaper,werep0rtedthestructuresofind0lealkal0ids;l9S-hydr0xy-tacamine,tabernaemontanine,l7-demethoxy-c0rynoxineB,l7-demethoxy-hydr0c0rynoxineB,20-epi-ervatamine,19,2O-dehydroervatamine,includinganewone,l9S-hydroxy-16-epi-tacaminefr0mthisspecies'.T…  相似文献   
23.
A New Taxane Diterpenoid from the Seeds of Taxus yunnanensis   总被引:1,自引:0,他引:1  
Plant from the genus of Taxus are a rich source of biologically active diterpennodsbelonging to the unique structural family of taxoids'. Although more than 300 taxoidswere isolated from yew tree', new taxoids still were isolated. In our continuing studieson the yew tree, we have previously isolated several new taxoids from seeds of theChinese yew, Taxus chinensiS var mairei. T yunnanensiS, and Japanese yew, TCuspidata'-'. Further investigation on the extract of the seeds of T yunnanensis …  相似文献   
24.
The non-alkaloid chemical constituents, which were isolated from the stems of Ervatamia yunnanensis Tsiang (Apocynaceae), have been reported in previous paper 1. As a part of our continuing research on the isolation of active compounds for anti-addictive …  相似文献   
25.
小红参中蒽醌苷的分离和鉴定   总被引:3,自引:0,他引:3  
陈毓群  罗雍容 《有机化学》1991,11(5):523-524
云南普米族常用活血药茜草科小红参(Rubia yunnanensis)的根部水溶性部分曾用于治疗心绞痛。王淑仙等发现,它对小鼠能明  相似文献   
26.
《Analytical letters》2012,45(14):2317-2331
The genus Stellaria (Caryophyllaceae) presents widely distributed plants often used in traditional medicine. Flavonoids are highly active plant secondary metabolites that may be involved in some of the effects of Stellaria plants. In this study, two new high-performance liquid chromatography–electrospray ionization tandem mass spectrometry (HPLC–ESI-MS-MS) methods were developed for the determination of flavonoids and isoflavonoids in plant material. The separations were performed on a reverse-phase C18 column with gradient elution using methanol and water with 0.5% acetic acid as the mobile phase. Multiple reaction monitoring was used for the tandem mass spectrometry detection and the two most intensive transitions were chosen for the identification of each analyte. The limits of detection and the limits of quantification were between 0.2 and 15.0 ng/mL and 0.6 and 50.0 ng/mL. The developed methods were successfully used for the analyses of four representatives of the genus Stellaria. All the studied herbs contained luteolin and its 7-O-glycosides, naringenin, kaempferol, quercetin, its glycoside rutin, apigenin, and its 7-O-glycoside. One coumarin, scopoletin, was also found. Isoflavones were primarily represented by genistein, genistin, and ononin. Some of the analytes were detected for the first time in Stellaria sp. The findings support that these methods are suitable for analyses of plant material.  相似文献   
27.
Taxayuntin I, a new 11 (15->l)abeotaxane, was isolated from the leaves and stems of Taxus yunnanensis. Its structure was elucidated on the basis of spectroscopic data.  相似文献   
28.
Two new benzoyl esters of glucose 1-O-(E)-4′-methoxybenzoyl-β-D-glucopyranose (1) and 1-O-(E)-4′-methoxybenzoyl-β-D-gluconic acid (2) were isolated from Lagotis yunnanensis, together with six previously known iridoid glucosides. The structures of these compounds were elucidated on the basis of spectral analysis, including 2D NMR spectroscopy. Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 529–530, November–December, 2006.  相似文献   
29.
30.
Three new indole alkaloids, 10‐methoxy‐16‐de(methoxycarbonyl)pagicerine ( 1 ), (5β)‐17‐O‐deacetyl‐5,11‐dimethoxyakuammiline ( 2 ), and ((16S,19E)‐N1‐(hydroxymethyl)isositsirikine ( 3 ) were isolated from the roots of Rauvolfia yunnanensis, together with seven known alkaloids. The structures of the new compounds were elucidated by in‐depth spectroscopic and mass‐spectrometric analyses.  相似文献   
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