Font Size: a A A

Phytochemical studies on medicinal plants: Alisma orientale and Desmodium styracifolium

Posted on:2006-09-11Degree:Ph.DType:Dissertation
University:The Chinese University of Hong Kong (People's Republic of China)Candidate:Zhao, MingFull Text:PDF
GTID:1453390008959844Subject:Chemistry
Abstract/Summary:
In the present study, two medicinal plants were investigated for their organic constituents. Plant samples were extracted and purified by chromatographic separation using a combination of methods. Each compound isolated was characterized by spectroscopic and physical data. A number of new chemical structures were found.; The investigation has led to the isolation and structural elucidation of fourteen pure compounds from an ethanol extract prepared from the dried rhizomes of Alisa orientale, including three types of skeletons: protostane triterpene, guaiane sesquiterpene and phytosterol. They were identified to be beta-sitosterol (1), (17S)-3, 11-dioxo-23-nor protost-12-en-23 (17)-olide (2), alisol B 23-acetate (3), alismol ( 4), alismoxide (5), alisol B (6), alisol A (7), 25-O-methylalisol A (8), 25-anhydroalisol A 24-acetate (9), 25-anhydroalisol A (10), alisol E 23-acetate (11), daucosterol 6'-stearate (12), (20R, 23S, 24R)-23, 24, 25-trihydroxy-2, 3-seco protost-13 (17)-en-3-oic acid 2, 11beta-lactone (13), and 13beta, 17beta-epoxyalisol A (14). Among them, compound 2 was a new naturally occurring skeleton of 23-nor protostane triterpene, and compound 13 a new 2, 3-seco-protostane triterpene.; Forty-six constituents have been identified from an ethanol extract prepared from the aerial parts of Desmodium styracifolium, including seven triterpenes: lupeol (15), lupeone (16), olean-12-ene-3beta, 22beta-diol (sophoradiol) (19), olean-12-ene-3beta, 22beta, 24-triol (soyasapogenol B) (20), (23Z)-9, 19-cycloart-23-ene-3beta, 25-diol (21), (24R)-cycloart-25-ene-3beta, 24-diol (24a), and (24S)-cycloart-25-ene-3beta, 24-diol (24b); one triterpene saponin: 3-O-[alpha-rhamnopyranosyl (1→2)-beta-galactopyranosyl (1→2)-beta-glucuronopyranosyl] soyasapogenol B (soyasaponin I) (53); three phytosterols: beta-sitosterol (17), stigmasterol (18), and daucosterol (47); sixteen isoflavanones and O-glycosides: 5, 7-dihydroxy-2', 4'-dimethoxy-isofavanone (homoferreirin) (22), 5, 7, 4'-trihydroxy-2'-methoxy-isofavanone (isoferreirin) (23), (3R)-5, 7-dihydroxy-2', 3', 4'-trimethoxy-isoflavanone (25a), (3S)-5, 7-dihydroxy-2', 3', 4'-trimethoxy-isoflavanone (25b), (3R)-5,{09}7-dihydroxy-2'-methoxy-3', 4'-methylenedioxy-isoflavanone (26a), (3S)-5, 7-dihydroxy-2'-methoxy-3, 4'-methylenedioxy-isoflavanone (26b),{09}5, 7, 3'-trihydroxy-2', 4'-dimethoxy-isoflavanone (secundiflorol H) (40), 5, 7, 2', 4'-tetrahydroxy-isoflavanone (dalbergiodin) (41), 3, 5, 7, 4'-tetrahydroxy-2, 2'-epoxyisoflavanone (42), (3R)-5, 7-dihydroxy-2', 3', 4'-trimethoxy-isoflavanone 7-O-beta-glucopyranoside (48a), (3S)-5, 7-dihydroxy-2, 3', 4'-trimethoxy-isoflavanone 7-O-beta-glucopyranoside (48b), (3R)-5, 7-dihydroxy-2'-methoxy-3', 4'-methylenedioxy-isofavanone 7-O-beta-(glucopyranoside (49a). (Abstract shortened by UMI.)...
Keywords/Search Tags:7-dihydroxy-2', 4'-trimethoxy-isoflavanone
Related items