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1.
It has been established that a polysaccharide from the pith of the stems ofAlthea flavovirens Boiss et Buhse growing in Azerbaidzhan (environs of the village of Dzhul'fy) has a branched molecule consisting of residues of ribose, rhamnose, glucose, and glucuronic and galacturonic acids (3:6:3:7:2). Among the products of the methylation of the polysaccharide reduced at the carboxy groups the following sugar derivatives have been identified: 2,3,4-tri-O-methyl-L-rhamnose, 3,4-di-O-methyl-L-rhamnose, 2,3,4,6-tetra-O-methyl-D-glucose, and 2,3,6-tri-O-methyl-D-glucose and 2,3,6-tri-O-methyl-D-galactose (unresolved mixture), and also 2,6-di-O-methyl-D-glucose (2:10:24:7:2).V. L. Komarov Botanical Institute, Academy of Sciences of the USSR, Leningrad. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 29–33, January–February, 1980.  相似文献   

2.
Three new ent‐atisane diterpenes, i.e., 17‐hydroxy‐ent‐atisan‐19‐oic acid ( 1 ), 17‐hydroxy‐ent‐atisan‐19‐oic acid methyl ester ( 2 ), and 16α,17‐dihydroxy‐ent‐atisan‐19‐al ( 3 ), together with five known phenolic compounds, i.e., gallic acid, ethyl gallate, protocatechuic acid, 3,4,4′‐tri‐O‐methylellagic acid, and α‐tocopherol, and two other known compounds, i.e., trans‐cinnamic acid and taraxerone, were isolated from the pericarp of Trewia nudiflora collected in Xishuangbanna, Yunnan Province, China. Their structures were elucidated by spectroscopic analysis including 1D‐ and 2D‐NMR. Trace amounts of maytansinoids were isolated by antifungal‐activity‐guided fractionation and determined by LC‐ESI‐MS analysis; they were prominent antifungal constituents in the pericarp of Trewia nudiflora.  相似文献   

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The polysaccharides of three cultivated varieties ofAlthea rosea have been investigated. The amounts of water-soluble polysaccharides and pectin substances in various organs of the plant have been determined. It has been shown that the maximum amount of water-soluble polysaccharides and pectin substances is present in the flowers. Their monosaccharide compositions have been studied. The physicochemical characteristics of the pectin substances are given.  相似文献   

6.
Summary 1. The dioxane lignins have been extracted from three species ofAlthea for the first time. On the basis of elementary and functional analyses, the semiempirical formulas of the phenylpropane structural units have been calculated.2. The molecular weight distributions have shown that the DLAs of these species ofAlthea are polydisperse, and in the case of the DLAs of the wild-growing species —A. rhyticarpa andA. nudiflora — the high-molecular weight fraction is predominant, while for the DLA ofA. rosea the low-molecular-weight fraction is predominant.3. In a study of the products of nitrobenzene oxidation it has been established that the DLA of all three species ofAlthea includes p-coumaryl, guaiacyl, and syringyl structural units.4. In the products of decomposition with metallic sodium in liquid ammonia 18 phenols have been identified the structures of which show the presence in the initial lignins of guaiacyl- and syringylpropane units with free OH groups in the side chains in the - and -positions to the aromatic nucleus.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 93–100, January–February, 1977.  相似文献   

7.
Two new seco-labdane diterpenoids, nudiflopene N (1) and nudiflopene O (2), and four known compounds were isolated from the leaves of Callicarpa nudiflora. The structures of the new compounds were established by 1D-, 2D-NMR, and HR-ESI-MS spectral analyses. Compounds 1–3 showed inhibitory activities on lipopolysaccharide-induced nitric oxide (NO) production in RAW264.7 cells, and new compounds 1–2 exhibited more potent inhibitory activity than compound 3. The cytotoxicity of compounds 1–3 against human hepatocellular carcinoma HepG2 cells and human gastric carcinoma SGC-7901 cells were evaluated, while all of them exhibited no cytotoxicity.  相似文献   

8.
A minor, unprecedented diterpene, 3β,17‐dihydroxycleistantha‐12,15‐dien‐2‐one ( 1 ), was isolated from the CHCl3‐soluble part of the EtOH extract of the pericarp of Trewia nudiflora. The structure of 1 was elucidated by means of 1D‐ and 2D‐NMR spectroscopic analyses as well as by HR‐MS. Also isolated were two known triterpenes, glutin‐5‐en‐3‐ol and olean‐18‐en‐3‐one (germanicone), as well as three known sterols, (22E,24R)‐5α,8α‐epidioxyergosta‐6,22‐dien‐3β‐ol, (22E,24R)‐5α,8α‐epidioxyergosta‐6,9(11),22‐trien‐3β‐ol, and (22E,24R)‐6‐methoxyergosta‐7,22‐dien‐3,5‐diol.  相似文献   

9.
Five ent‐atisane diterpenoids, including three new ones, i.e., (16α)‐17‐hydroxy‐ent‐atisan‐19‐oic acid methyl ester ( 1 ), (16α)‐17‐dihydroxy‐ent‐atisan‐19‐oic acid methyl ester ( 2 ), (16α)‐ent‐atisan‐16,17,19‐triol ( 3 ), and two known compounds, i.e., 17‐hydroxy‐ent‐atisan‐19‐oic acid ( 4 ), (16α)‐16,17‐dihydroxy‐ent‐atisan‐19‐al ( 5 ), together with one known diterpene glycoside, i.e., sumogaside, two known triterpenes, i.e., germanicone and (3β)‐β‐amyrin, three known phenolic compounds, i.e., (+)‐gallocatechin, (+)‐catechin, and gallic acid, and two known sterols, i.e., β‐sitosterol and daucosterol, were isolated from the callus cultures of Trewia nudiflora. Their structures were elucidated by spectroscopic analysis including 1D‐ and 2D‐NMR experiments. No maytansinoids were isolated or detected by LC‐ESI‐MS in the extracts of the calli, which suggests that the callus cultures can not produce maytansinoids under these conditions.  相似文献   

10.
Five new cardenolides and one new cardiac aglycone, i.e., (5α)‐sarmentogenin 3‐(α‐L ‐rhamnopyranoside) ( 1 ), (5α)‐sarmentogenin ( 2 ), 11‐oxouzarigenin 3‐(α‐L ‐rhamnopyranoside) ( 3 ), (5α)‐gitoxigenin 3‐(α‐L ‐rhamnopyranoside) ( 4 ), (5α)‐oleandrigenin 3‐(α‐L ‐rhamnopyranoside) ( 5 ), and (5α)‐oleandrigenin 3‐[β‐D ‐glucopyranosyl‐(1 → 4)‐α‐L ‐rhamnopyranoside] ( 6 ), together with two known cardenolides, i.e., frugoside (= (3β,5α)‐3‐[(6‐deoxy‐β‐D ‐allopyranosyl)oxy]‐14,19‐dihydroxycard‐20(22)‐enolide) and (17α)‐ascleposide (= (3β,5α,17α)‐3‐[(6‐deoxy‐α‐D ‐allopyranosyl)oxy]‐14‐hydroxycard‐20(22)‐enolide), were isolated from the stem bark of Trewia nudiflora L. (Euphorbiaceae) collected in Xishuangbanna, Yunnan Province, China. Their structures were established by spectroscopic studies. Cardenolides were first found in the genus Trewia (Euphorbiaceae).  相似文献   

11.
Polyoxypregnanes from the stems of Marsdenia tenacissima   总被引:1,自引:0,他引:1  
From the stems ofMarsdenia tenacissima two new polyoxypregnanes were isolated, their structures were elucidated by 1D, 2D-NMR as 11α,12β-di-O-tigloyl-tenacigenin B (1) and tenacigenoside E (2).  相似文献   

12.
A novel amide, cinnabutamine (1), along with five known amides, cinnaretamine (2), N-trans-caffeoyl-5-hydroxytyramine (3), N-trans-feruloyltyramine (4), N-trans-feruloyl-5-methoxytyramine (5) and N-cis-feruloyl-5-methoxytyramine (6), were isolated from the stems of Cinnamomum burmannii (Lauraceae). Their structures were characterized and identified by spectral analysis.  相似文献   

13.
Four new xanthones, 1‐methoxy‐3,7,8‐trihydroxyxanthone (1), 1‐methoxy‐4,7,8‐trihydroxyxanthone (2), 1‐methoxy‐4,7‐dihydroxyxanthone (3), and 1,4‐dimethoxy‐2,7‐dihydroxyxanthone (4) were isolated from the stems of Cratoxylum cochinchinense along with four known xanthones (5–8). The structures of new compounds were determined by extensive spectroscopic analyses, mainly 1D and 2D NMR and HRESIMS data. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

14.
Five new compounds, hibicuslide A (1), hibicuslide B (2), hibicuslide C (3), hibicutaiwanin (4), hibicusin (5), and fifty-one known compounds have been isolated from the stems of Hibiscus taiwanensis. The structures of these compounds were determined by spectroscopic and chemical transformation methods. Among them, mansonone H (19) and uncarinic acid A (30) inhibited HIV replication in H9 lymphocyte cells. The 9,9'-O-feruloyl-(-)-secoisolaricinresinol (12), myriceric acid C (29), and uncarinic acid A (30) showed cytotoxic activity against human lung carcinoma and breast carcinoma.  相似文献   

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Lipids from roots ofAlthaea nudifloraandA. Armeniacawere studied. The carbohydrate and fatty-acid compositions were found. The lipids ofA. NudifloraandA. Armeniacacontain 22.3 and 12.6%, respectively, of cyclopropenoid fatty acids, the physical chemical properties of which are presented. The optimal degree of grinding, temperature, and raw-material-to-extractant ratio for aqueous extraction of water-soluble polysaccharides from althaea roots were chosen from a single statistically significant experiment  相似文献   

18.
Fractionation of the polysacchride complex of the inflorescences of pineapple weed has given a galacturonan and a pectic acid. The structures of the galacturonan and pectic acid have been studied by the methods of enzymatic hydrolysis, periodate oxidation, and exhaustive methylation. It has been established that the galacturonan is a linear polysaccharide consisting of D-galacturonic acid residues in the pyranose form with α-1→4-bonds. The main polysaccharide chain of the pectic acid consists of D-galacturonic acid residues in the pyranose form, D-galactose, L-arbinose, and D-xylose residues are covalently bound to carbon atoms 2 or 3 of the main chain of the polysaccharide.  相似文献   

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The stems of Akebia quinata have been analyzed for their triterpene glycoside constituents, resulting in the isolation of six new triterpene glycosides, along with 19 known ones. On the basis of extensive spectroscopic analysis, including 2D NMR data, and chemical evidence, the structures of the new compounds were deter-mined to be 3beta-[(O-beta-D-glucuronopyranosyl-(1-->3)-alpha-L-arabinopyranosyl)oxy]olean-12-en-28-oic acid O-alpha-L-rhamnopyranosyl-(1-->4)-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl ester, 3beta-[(O-beta-D-glucuronopyranosyl-(1-->3)-O-[alpha-L-rhamnopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl)oxy]olean-12-en-28-oic acid O-alpha-L-rhamnopyranosyl-(1-->4)-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl ester, 3beta-[(O-beta-D-glucuronopyranosyl-(1-->3)-alpha-L-arabinopyranosyl)oxy]-23-hydroxyolean-12-en-28-oic acid O-alpha-L-rhamnopyranosyl-(1-->4)-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl ester, 3beta-[(O-beta-D-glucuronopyranosyl-(1-->3)-O-[alpha-L-rhamnopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl)oxy]-23-hydroxyolean-12-en-28-oic acid O-alpha-L-rhamnopyranosyl-(1-->4)-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl ester, 3beta-[(O-beta-D-glucopyranosyl-(1-->3)-O-[alpha-L-rhamnopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl)oxy]-29-hydroxyolean-12-en-28-oic acid, and 3beta-[(O-beta-D-glucopyranosyl-(1-->3)-O-[alpha-L-rhamnopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl)oxy]-23,29-dihydroxyolean-12-en-28-oic acid, respectively. The main triterpene glycosides contained in the stems of A. quinata were found to have two sugar units at C-3 and C-28 of the aglycone in this study, whereas those of Akebia trifoliate were reported to possess one sugar unit at C-28 of the aglycone. It may be possible to distinguish between A. quinata and A. trifoliate chemically by comparing their triterpene glycoside constituents.  相似文献   

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