Among the six simple phenolic glucosides (compounds 1-4, 6-7), two were new compounds. Simple phenolic glucoside is rare in Sapindaceae, and it may be of chemotaxonomic significance for Eurycorymbus as an independent genus within the family Sapindaceae. / Besides the novel compounds 3, 7, and 28, compounds 1, 2, 4-6, 8-10, 12-16, and 18-27 were isolated from E. cavaleriei for the first time. / In the present study, twenty eight compounds were isolated from the stems of E. cavaleriei. Twenty seven compounds had been identified including the new structures eurycorymboside A (3), eurycorymboside B (7), and eurycorymbic acid (28). The twenty four known compounds are vanillic acid 4-O-beta-D-glucoside (1), glucosyringic acid (2), koaburaside ( 4), fraxin (5), tachioside (6), (-)-lyoniresinol 3a-O-beta-D-glucopyranoside (8), (-)-isolariciresinol 3a-O-beta-D-glucopyranoside (9), kaempferol 3-O-beta-D-glucopyranosyl-(1 → 4)-alpha-L-rhamnopyranosy1-7- O-alpha-L-rhamnopyranoside (10), 5'-demethyl aquillochin (11), kaempferitrin (12), scopoletin (13), (-)-syringaresinol (14), cleomiscosin A (15), cleomiscosin B (16), daucosterol (18), methyl salicylate ( 19), ethyl salicylate (20), 4-hydroxy-3,5-bis(3-methyl-2-butenyl)benzaldehyde (21), 1-octatriacontanol (22), stigmasterol ( 23), beta-sitosterol (24), acetyloleanolic acid ( 25), vanillin (26), and 3-oxotirucalla-7,24-dien-21-oic acid (27). Compound 17 was tentatively determined to be either cleomiscosin C or D. / Sapindaceae is a family of flowering plants with 145 genera and 1490 species, distributed mainly in tropical regions, with a few genera growing in the temperate zone. Eurycorymbus cavaleriei (Levl.) Rehd. et Hand.-Mazz. is the only species of the genus Eurycorymbus, belonging to Sapindaceae. It is a dioecious, rare and endemic tree species of China, being listed in the National plant protection (level two). Sapindaceae is an important family with strong biological activities. However, few phytochemical studies on E. cavaleriei had been reported. The present study is focused on the phytochemical investigation of E. cavaleriei for the isolation of active natural compounds. / The antioxidant activity of the phenolic glucosides was evaluated by DPPH free radical scavenging assay. Koaburaside (4) exhibited antioxidant activity with IC50 values of 9.0 muM. In in vitro experiment, koaburaside also showed weak inhibitory activity against influenza A neuraminidase. But none of the phenolic glucosides showed cytotoxic activity against A-549, Bel-7402, and HCT-8 cells in vitro. / The sample was collected from the Nanyue Arboretum (Hunan, China), and identified as the stem of E. cavaleriei. Air-dried stems (5 kg) were extracted with 90% ethanol. After removing excessive solvent under reduced pressure, the syrup obtained was suspended in water, followed by successive partition with petroleum ether (b.p. 60--80°C), dichloromethane, ethyl acetate, and n-butanol. The different fractions were purified by silica gel, RP-18, Sephadex LH-20, MCI Gel CHP20P, and semi-preparative HPLC. The structures were established on the basis of spectral analysis (including HR-MS, 1D- and 2D-NMR). / He, Yi. / Adviser: Chun-Tao Che. / Source: Dissertation Abstracts International, Volume: 73-01, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 120-137). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
| Identifer | oai:union.ndltd.org:cuhk.edu.hk/oai:cuhk-dr:cuhk_344620 |
| Date | January 2010 |
| Contributors | He, Yi, Chinese University of Hong Kong Graduate School. Division of Chinese Medicine. |
| Source Sets | The Chinese University of Hong Kong |
| Language | English, Chinese |
| Detected Language | English |
| Type | Text, theses |
| Format | electronic resource, microform, microfiche, 1 online resource (xx, 180 leaves : ill.) |
| Rights | Use of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/) |
Page generated in 0.0019 seconds