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81.
紫珠叶的化学成分研究Ⅰ 总被引:5,自引:2,他引:3
从马鞭草科紫球叶的乙醇提取物中分得5个化合物,经理化性质和光谱数据分别鉴定为:三十五烷(Ⅰ)、α-香树脂醇(Ⅱ)、四十五碳酸(Ⅲ)、5-羟基-4′,3,6,7-四甲氧基-黄酮(Ⅳ)、豆甾醇(Ⅴ)。除豆甾醇外,其余化合物均为首次从该属植物中分得。 相似文献
82.
Triterpenoid saponins from Schefflera arboricola 总被引:5,自引:0,他引:5
Nine triterpenoid saponins were isolated from the leaves and stems of Schefflera arboricola. The saponins were characterised, on the basis of chemical and spectral evidence, as 3-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucuronopyranosyl] oleanolic acid, 3-O-[alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucuronopyranosyl] echinocystic acid, 3-O-[beta-D-apiofuranosyl-(1-->4)-beta-D-glucuronopyranosyl] oleanolic acid 28-O-beta-D-glucopyranosyl ester, 3-O-alpha-L-ramnopyranosyl-(1-->4)-[alpha-L-arabinopyranosyl-(1-->2)-] beta-D-glucuronopyranosyl oleanolic acid, 3-O-alpha-L-rhamnopyranosyl-(1-->4)-[alpha-L-arabinopyranosyl-(1-->2)-] beta-D-glucuronopyranosyl oleanolic acid 28-O-beta-D-glucopyranosyl ester, 3-O-alpha-L-rhamnopyranosyl-(1-->4)-[beta-D-galactopyranosyl-(1-->2)-] beta-D-glucuronopyranosyl oleanolic acid, 3-O-alpha-L-rhamnopyranosyl-(1-->4)-[beta-D-galactopyranosyl-(1-->2)-] beta-D-glucuronopyranosyl oleanolic acid 28-O-beta-D-glucopyranosyl ester, 3-O-beta-D-apiofuranosyl-(1-->4)-[alpha-L-arabinopyranosyl-(1-->2)-] beta-D-glucuronopyranosyl oleanolic acid and 3-O-beta-D-apiofuranosyl-(1-->4)-[alpha-L-arabinopyranosyl-(1-->2)-] beta-D-glucuronopyranosyl oleanolic acid 28-O-beta-D-glucopyranosyl ester. 相似文献
83.
Triterpenoids from Viburnum suspensum 总被引:3,自引:0,他引:3
Three triterpenoids, 3-oxo-11,13(18)-oleanadien-28-oic acid, 24-hydroxy-3-oxo-11,13(18)-oleanadien-28-oic acid, 6β-hydroxy-3-oxo-11,13(18)-oleanadien-28-oic acid have been isolated together with the previously known virgatic acid, vibsanin B and 3-hydroxyvibsanin E from the leaves of Viburnum suspensum. Their structures were determined by spectroscopic methods and by comparison of their NMR spectral data with those of the previously known 11,13(18)-oleanadien-3β-ol. 相似文献
84.
Four hitherto unknown triterpenoids, including one euphane, namely wilfordeuphone (1), and three friedelanes, namely wilforic acids G − I (2–4), were isolated from the ethanol extract of the roots of Tripterygium wilfordii. The absolute configuration of 1 was established by single crystal X-ray diffraction. In addition, this study is the first to report euphane-type triterpenoid in the genus Tripterygium. Compound 1 exhibited the moderate cytotoxic activity when evaluated against five human cancer cell lines (HL-60, A-549, SMMC-7721, MCF-7, and SW-480), with IC50 values ranging from 14.0–26.7 μM. 相似文献
85.
Three (1,2,4) and one known (3) triterpenoid saponins were isolated from the bark of Albizia procera. The saponins were characterized as 3-O-[beta-D-xylopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1-->6)-2-acetamido-2-deoxy-beta-D-glucopyranosyl] echinocystic acid (1), 3-O-[alpha-L-arabinopyranosyl-(1-->2)-beta-D-fucopyranosyl-(1-->6)-2-acetamido-2-deoxy-beta-D-glucopyranosyl] echinocystic acid (2) and 3-O-[beta-D-xylopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1-->6)-2-acetamido-2-deoxy-beta-D-glucopyranosyl] acacic acid lactone (4). Their structures were elucidated by 1D and 2D NMR experiments, FABMS as well as chemical means. Saponins 1 and 3 exhibited cytotoxicity against HEPG2 cell line with IC50 9.13 microg/ml and 10 microg/ml, respectively. 相似文献
86.
Five new triterpenoid saponins from the Roots of Camellia oleifera C. Abel with cytotoxic activities
Five new triterpenoid saponins, oleiferosides P–T (1–5) were isolated from the EtOH extract of the roots of Camellia oleifera C. Abel. The structures of saponins 1–5 were elucidated on the basis of integrated spectroscopic techniques. All the compounds were characterized to be oleanane-type saponins with sugar moieties linked to the C-3 of the aglycone. By using the MTT assay, an in vitro analysis of the cytotoxic activities of these saponins on the human tumor cell lines (lung adenocarcinoma A549 cells, hepatic carcinoma SMMC-7721 cells and breast cancer MCF-7 cells). Among them, compound 4 showed a certain cytotoxic activity against all the tested cell lines. 相似文献
87.
Cárdenas C Quesada AR Medina MA 《Biochemical and biophysical research communications》2004,320(2):402-408
Ursolic acid is a triterpenoid with pleiotropic biological effects. In this report, we study the effects of ursolic acid on different key steps of angiogenesis. Our results show that ursolic acid is able to inhibit key steps of angiogenesis in vitro, including endothelial cell proliferation, migration, and differentiation. At the same time, it seems to stimulate other key steps of angiogenesis, such as extracellular matrix degradation by MMP-2 and urokinase. Although ursolic acid can inhibit in vivo angiogenesis in the CAM assay, the different signs of the effects it causes on different steps of angiogenesis force one to be cautious concerning its anti-angiogenic potential. 相似文献
88.
Further saponins from Meryta lanceolata 总被引:2,自引:0,他引:2
Five new oleanane-type saponins along with 11 known ones were isolated from the leaves and stems of Meryta lanceolata. The new saponins were characterised by spectroscopic analysis including FAMS, 1 and 2D NMR experiments and the results of hydrolysis as 3-O-[beta-d-glucopyranosyl-(1-->2)-beta-d-glucuronopyranosyl] hederagenin 28-O-[alpha-l-rhamnopyranosyl-(1-->4)-beta-d-glucopyranosyl-(1-->6)-beta-d-glucopyranosyl] ester, 3-O-[beta-d-glucopyranosyl-(1-->2)-beta-d-glucuronopyranosyl] oleanolic acid 28-O-[alpha-l-rhamnopyranosyl-(1-->4)-beta-d-glucopyranosyl-(1-->6)-beta-d-glucopyranosyl]ester, 3-O-[beta-d-glucopyranosyl-(1-->2)-beta-d-glucuronopyranosyl] oleanolic acid 28-O-[alpha-l-rhamnopyranosyl-(1-->4)-beta-d-6-O-acetyl glucopyranosyl-(1-->6)-beta-d-glucopyranosyl]ester, 3-O-[beta-d-glucopyranosyl-(1-->3)-beta-d-glucopyranosyl-(1-->3)-alpha-l-arabinopyranosyl] oleanolic acid 28-O-[alpha-l-rhamnopyranosyl-(1-->4)-beta-d-glucopyranosyl-(1-->6)-beta-d-glucopyranosyl] ester and 3-O-[beta-d-glucopyranosyl-(1-->2)-beta-d-glucuronopyranosyl] hederagenin, respectively. 相似文献
89.
Cytotoxic triterpenes from the aerial roots of Ficus microcarpa 总被引:7,自引:0,他引:7
Six triterpenes, 3beta-acetoxy-12,19-dioxo-13(18)-oleanene (1), 3beta-acetoxy-19(29)-taraxasten-20alpha-ol (2), 3beta-acetoxy-21alpha,22alpha-epoxytaraxastan-20alpha-ol (3), 3,22-dioxo-20-taraxastene (4), 3beta-acetoxy-11alpha,12alpha-epoxy-16-oxo-14-taraxerene (5), 3beta-acetoxy-25-methoxylanosta-8,23-diene (6) along with nine known triterpenes, 3beta-acetoxy-11alpha,12alpha-epoxy-14-taraxerene (7), 3beta-acetoxy-25-hydroxylanosta-8,23-diene (8), oleanonic acid (9), acetylbetulinic acid (10), betulonic acid (11), acetylursolic acid (12), ursonic acid (13), ursolic acid (14), and 3-oxofriedelan-28-oic acid (15) were isolated from the aerial roots of Ficus microcarpa, and their structures elucidated by spectroscopic methods. The in vitro cytotoxic efficacy of these triterpenes was investigated using three human cancer cell lines, namely, HONE-1 nasopharyngeal carcinoma, KB oral epidermoid carcinoma, and HT29 colorectal carcinoma cells. Compound 8 and pentacyclic triterpenes 9-15 possessing a carboxylic acid functionality at C-28 showed significant cytotoxic activities against the aforementioned cell lines and gave IC50 values in the range 4.0-9.4 microM. 相似文献
90.
多花黄芪的三萜皂甙研究 总被引:1,自引:0,他引:1
豆科黄芪属(Astragalus)药用植物的三萜皂甙具有促进微循环和强心作用[1,2],临床上可明显改善心力衰竭病人的心功能。载入青海省新版药品标准[3]的黄芪属植物多花黄芪(AstragalusfloridusBenth.)其化学成分尚未见报道。为科学评价其质量,进一步扩大黄芪药源,作者对多花黄芪的化学成分进行了研究,从其干燥根中提取的总甙粗品部分,经硅胶柱层析和结晶纯化,分得5种三萜皂甙成分,通过光谱分析和化学方法,鉴定为绵毛黄芪甙(1)、黄芪皂甙(2)、黄芪皂甙(3)、绵毛黄芪甙(4)和膜荚黄芪甙(5)[4~7]。实 验 部 分熔点用4显微熔点测定仪测定,温度计… 相似文献