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1.
2.
Cratylia mollis Mart ex. Benth is a species belonging to the Leguminosae family that exists throughout South America, and it is one of the most abundant plants in northeastern Brazil, especially in the semiarid region. This plant is popularly known as “camaratu” and “camaratuba”, and the leaves and stems of this species are used as a substitute for cattle's alimentation during the dry season. The chemical investigation of the methanolic extract from leaves and stems of C. mollis led to the isolation of new flavans named 4,2′,3′-trihydroxy-4′-methoxy-6,7-(methylenedioxy) isoflavan, 7,2′-dihydroxy-6-methoxyflavan, 7,3′-dihydroxy-6,2′-dimethoxyflavan, 7-hydroxy-6-methoxyflavan, 2′-hydroxy-6,7-(methylenedioxy) flavan, 2R*,3S*-7,2′-dihydroxy-6-methoxy-flavan-3-ol, and 2R*,3S*-7,3-dihydroxy-6,2′-dimethoxyflavan-3-ol and an unusual flavan (11H-benzofuro[3,2-b][1] benzopyran-2-methoxy,3-hydroxy,5a,10a-dihydro) named (3R*,2R*)-3-O-2′-7-hydroxy-6-methoxyflavan. The structures of the new compounds were determined using spectroscopic methods.  相似文献   

3.
Four phenolic compounds, (2R)-3-(4′-hydroxyphenyl) lactic acid, trans-cinnamic acid (2), protocatechuic acid (3) and rutin (4), and three ecdysteroids, amarasterone A1 (5), makisterone C (6) and ponastrone A (7) were isolated and identified from the young fronds of Diplazium esculentum (Retz.) Sw. (Athyriaceae). The structures of these compounds were elucidated on the basis of NMR spectral data and comparison with literature values. Compounds 1, 2 and 57 were isolated for the first time from title plant. Their structure elucidation and chemotaxonomic significance are explained in detail.  相似文献   

4.
A cyanogenic glycoside - 6'-O-galloylsambunigrin - has been isolated from the foliage of the Australian tropical rainforest tree species Elaeocarpus sericopetalus F. Muell. (Elaeocarpaceae). This is the first formal characterisation of a cyanogenic constituent in the Elaeocarpaceae family, and only the second in the order Malvales. 6'-O-galloylsambunigrin was identified as the principal glycoside, accounting for 91% of total cyanogen in a leaf methanol extract. Preliminary analyses indicated that the remaining cyanogen content may comprise small quantities of sambunigrin, as well as di- and tri-gallates of sambunigrin. E. sericopetalus was found to have foliar concentrations of cyanogenic glycosides among the highest reported for tree leaves, up to 5.2 mg CN g(-1) dry wt.  相似文献   

5.
Phytochemical study of the leaves and the stem bark of Pseudospondias microcarpa (A. Rich.) Engl. afforded eight phenolic compounds: scopoletin (1), ferulic acid (2), isovitexin (3), rhoifolin (4), quercetin 3-O-α-L-rhamnopyranoside (5), justicialoside A (6), granduloside A (7) and pithecellobiumol B (8). The structures of the isolated compounds were elucidated by spectroscopic means including 1D and 2D NMR and MS, and by comparison with previously reported data. This is the first report on the isolation of these compounds from the genus Pseudospondias. The chemotaxonomic significance of the isolated compounds within the family Anacardiaceae is discussed.  相似文献   

6.
Eleven compounds isolated from the growth inhibiting active fraction of male flowers of Cucurbita pepo, were identified as p-hydroxybenzaldehyde, anisyl alcohol, p-hydroxybenzyl methyl ether, p-hydroxybenzyl alcohol, veratryl alcohol, isovanillyl alcohol, p-coumaric acid, phloretic acid, benzyl-β-d-glucoside, 4-methoxybenzyl-β-d-glucoside and 3, 4-dimethoxybenzyl-β-d-glucoside. Each compound was assayed for growth inhibiting activity using lettuce seedlings; three showed strong activity, whereas the glucosides were inactive.  相似文献   

7.
A new trinorsesterterpene glycoside was isolated from the ethanol extract of the American fern Woodwardia virginica having a 3-[6-(4,8-dimethyl-nona-1,3,7-trienyl)-4-hydroxy-2,6-dimethyl-cyclohex-1-enyl]-3-hydroxypropionic acid, as the aglycone and a saccharide moiety linked at C-4 to glucoses, xylose or arabinofuranose. The structure was elucidated using extensive spectroscopic analysis (1D and 2D NMR, MS, IR and UV) including determination of absolute stereochemistry by means of the MTPA and PGME derivatives and also by chemical methods.  相似文献   

8.
Eight phenolic compounds, including two catechins (1 and 2), two proanthocyanidins (3 and 4), three lignans (57), and one phenol (8), were isolated from roots of Vaccinium dunalianum Wight (Ericaceae), together with two triterpenes (9 and 10). All of them were isolated from the title plant for the first time. Their chemical structures were established based on the extensive MS and NMR spectroscopic analysis. Compounds 610 acquired initially from the genus Vaccinium, showed some significances in chemotaxonomy.  相似文献   

9.
Chemical investigation of the root of Rosa laevigata led to the isolation of sixteen phenolic compounds, including seven flavonoids (17), five condensed tannins (812), two stilbenes (13 and 14) and two benzoic acid derivatives (15 and 16). Their structures were identified as (+)-catechin (1), (+)-gallocatechin (2), (2R, 3S, 4S)-cis- leucocyanidin (3), (2R, 3S, 4S)-cis-leucofisetinidin (4), (2S, 3R, 4R)-cis- leucofisetinidin (5), dehydrodicatechin A (6), phloridzin (7), procyanidin B3 (8), fisetinidol-(4α, 8)-catechin (9), guibourtinidol- (4α, 8)-catechin (10), ent- isetinidol -(4α, 6)-catechin (11), fisetinidol-(4β, 8)-catechin (12), (Z)-3-methoxy-5-hydroxy- stilbene (13), (Z)-piceid (14), gallic acid (15) and 4-hydroxybenzoic acid- 4-O-β-D-glucopyranoside (16). Among them, compounds 3–7, 9–14, and 16 were isolated from R. laevigata for the first time, and compounds 3–7, 9, 10, 1214 and 16 were reported for the first time from the genus Rosa. The chemotaxonomic significance of these compounds was summarized.  相似文献   

10.
The cyanogenic diglycoside lucumin ((R)-mandelonitrile-β-d-primeveroside) and monoglucoside prunasin ((R)-mandelonitrile-β-d-glucoside) were isolated from the foliage of the rare Australian rainforest tree species Clerodendrum grayi (Lamiaceae). This is the first reported isolation of the diglycoside lucumin from vegetative tissue (foliage), and the first reported co-occurrence of lucumin and prunasin. Furthermore, unusually, the diglycoside lucumin was the most abundant cyanogen accounting for approximately 60% of total cyanide in a leaf tissue.  相似文献   

11.
Twelve compounds were isolated from the ethyl acetate soluble portion of the 70% hydroalcoholic extract from the leaves of Zanthoxylum nitidum (Roxb.) DC. All of the compounds were determined on the basis of UV, IR, NMR and MS and comparison with literature. Among them, compounds 4, 7, 10 and 12 were first acquired from Rutaceae, compound 2 was isolated from the genus of Zanthoxylum for the first time and compounds 1, 3, 6, 9, 11 were isolated from Z. nitidum for the first time. Our present study exhibited the taxonomic relationships between Z. nitidum and other species in the same genus; those between Rutaceae and other families. Furthermore, we have summarized the chemotaxonomic significance of these compounds in Rutaceae and Zanthoxylum.  相似文献   

12.
13.
从朝鲜蓟(Cynara scolymus)叶中分离得到2个酚性糖苷化合物,其中一个是新化合物,通过波谱学方法确定其结构为2-甲氧基-4-(2,3-二羟基-丙酰基)-苯基-1—O-(6′-O-没食子酰基)-β-D-吡喃葡萄糖苷(1)。  相似文献   

14.
15.
鳞果星蕨属是从星蕨属中划分出来的,其孢子囊群上幼时覆盖着近无柄的鳞片状隔丝。本文在 研究星蕨亚科植物标本和野外考察的基础上,结合解剖学、孢粉学、生态学和植物地理学资料,对鳞果星蕨属植物作了修订。承认该属的独立性,并研究了有关种类的变异幅度,将星蕨属中有盾状隔丝的种类归入本属,承认鳞果星蕨和云南鳞果星蕨两个种。  相似文献   

16.
Agastache rugosa (Fisch. & C.A.Mey.) Kuntze has been widely used as a food spice and a remedy for colds in Korea, China and Japan. In this study, one new flavone glycoside (1) along with six flavonoids (27), nine phenyl glycosides (816) and three megastigmane glycosides (1719) were isolated from the leaves of A. rugosa. By extensive spectroscopic methods including 1D and 2D NMR, and MS data, the structure of the new compound (1) was elucidated as acacetin 7-O-β-(6″-(E)-crotonylglucopyranoside). From present investigation, compound 1 and 719 were isolated for the first time from the genus Agastache and 1, 16, 18 and 19 in the Lamiaceae family.  相似文献   

17.
The genus Lepidomicrosorum was separated from Microsorum Link by Ching and Shing in 1983. It is characterized by minute scattered sori covered with peltate and subsessile paraphyses when young. Tagawa detected that Polypodium subhastatum Baker, the type of this new genus, has this kind of paraphyses and thus transferred this species to Neocheiropteris Christ in 1952, a genus with divided lamina. During our study of the Microsoroideae, a revision of Lepidomicrosorum from China and neighboring regions is made on the basis of field and herbarium observation and evidence from anatomy, spore morphology, ecology, and distribution. Lepidomicrosorum is recognized as an independent genus and the demarcation line of its species is reconfirmed. Species with peltate scale-like paraphyses in Microsorum were transferred to Lepidomicrosorum. As a result, two species are recognized in this species, i.e.L.buergerianum (Miq.) Ching et Shing and L. hymenodes (Kunze)L. Shi et X. C. Zhang.  相似文献   

18.
Fronds of the fern Microsorum scolopendria are widely used in traditional medicine in the Society Islands. They were investigated for the presence of ecdysteroids, which might be responsible for at least some of their medicinal properties. M. scolopendria represents an excellent source of ecdysone (0.16% of dry weight) and 20‐hydroxyecdysone (0.20%), and also contains significant amounts (0.01–0.02%) of makisterones A and C, inokosterone and amarasterone A, together with lower amounts of poststerone and of a compound tentatively identified as 24,28‐diepi‐cyasterone. During this study, three new minor phytoecdysteroids, namely 20‐deoxymakisterone A, a 25(?)‐epimer of amarasterone A and 25‐deoxyecdysone 22‐glucoside were also isolated by a combination of normal‐ and reversed‐phase HPLC and subsequently identified by NMR. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

19.
The phytochemical study of the alcoholic extract obtained from Bipinnula fimbriata (Poepp.) I.M.Johnst., allowed to isolate three metabolites, corresponding to the butanolide kinsenoside (1) and to two dihydrostilbene derivatives, which have been assigned as 3-methoxy-5-{2-[3-methoxy-2-(3-methylbut-2-en-1-yl)-phenyl]ethyl}phenol (2) and 4-[2-(3-hydroxy-5-methoxyphenyl)ethyl]-2-(3-methylbut-2-en-1-yl)phenol, also named cannabistilbene I (3). The occurrence of these compounds is consistent with the current classification of the genus and allowed to point out some chemotaxonomic considerations.  相似文献   

20.
The genus Rhaponticoides, recently segregated from the genus Centaurea, belongs to the family Asteraceae (tribe Cardueae). Rhaponticoides mykalea (Hub.-Mor.) M.V.Agab. & Greuter is an endemic species narrowly distributed in the Aegean part of Turkey. Owing to the existing anthropogenic impacts (such as urbanization and road construction) throughout its distribution range, the species has been the subject of several conservation studies. Phytochemical research on the aerial parts of R. mykalea led to the isolation of a new flavonoid, namely patuletin 7-O-(6″-E-sinapyl)-β-glucopyranoside, together with four known flavonoids from n-butanol extract. The structures of all isolated compounds were elucidated by spectroscopic analysis (1D and 2D NMR, HR-ESI-MS), as well as by comparison with the relevant literature data. All of the compounds have been isolated from the genus Rhaponticoides for the first time.  相似文献   

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