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1.
Giuliano Delle Monache Franco Delle Monache Peter G. Waterman Elizabeth G. Crichton Roberto Alves De Limas 《Phytochemistry》1984,23(8):1757-1759
8-Deoxygartanin and two new xanthones, 1,5-dihydroxy-6′,6′-dimethyl-2H-pyrano(2′,3′:3,2)-6″,6″-dimethyl-2H-pyrano(2″,3″:6,7)xanthone and 1,5,6-trihydroxy-6′,6′-dimethyl-2H-pyrano(2′,3′:3,2)-7-(3-methylprop-2-enyl)xanthone, have been isolated from the roots of Rheedia gardneriana. The latter of the two new xanthones has been assigned the trivial name 7-prenyljacareubin while the former has the structure erroneously assigned to pyranojacareubin reported from Garcinia densivenia. The correct identity of the G. densivenia xanthone has been shown to be rheediaxanthone-A. 相似文献
2.
Swertia mussotii Fraeh (Family Gentianaceae) is a herb used as medicine for liver diseases in Tibetan. Its principal antihepatitisic constituents, oleanolic acid and mangiferin, have been reported. The present paper reports eight xanthones obtained from this plant. Their structures have been identified as 1,8-dihydroxy-3,5-dimethoxyxanthone Ⅰ, 1-hydroxy-3,5-dimethoxyxanthone Ⅱ, 1-hydroxy-3,7,8-trimethoxyxanthone Ⅲ, 8-hydroxy- 1,3,5-trimethoxyxanthone Ⅳ, 1,8-dihydroxy-3,7-dimethoxyxanthone Ⅴ, 1,7,8-trihydroxy- 3-methoxyxanthone Ⅵ, 1,7-dihydroxy-3,4,8-trimethoxyxanthone Ⅶ, and 1,3,8-trihydro- xy-5-methoxyxanthone Ⅷ. Of them, 1,7-dihydroxy-3,4,8-trimethoxyxanthone is a new natural product. 相似文献
3.
《Phytomedicine》2010,17(12):1144-1150
In this study, six major xanthones, isolated and identified from Halenia elliptica were investigated for their vasodilatory actions in isolated rat coronary artery. The xanthones, including 1-hydroxy-2,3,5-trimethoxy-xanthone (HM-1), 1-hydroxy-2,3,4,7-tetramethoxy-xanthone (HM-2), 1-hydroxy-2,3,4,5-tetramethoxy-xanthone (HM-3), 1,7-dihydroxy–2,3,4,5-tetramethoxy-xanthone (HM-4), 1,5-dihydroxy-2,3-dimethoxy-xanthone (HM-5) and 1,7-dihydroxy-2,3-dimethoxy-xanthone (HM-7) caused vasodilation in the coronary artery pre-contracted with 1 μM 5-hydroxytryptamine (5-HT), with EC50 values ranging from 1.4±0.1 μM (HM-1) to 6.6±1.4 μM (HM-2). The EC50 values of the other xanthones were between those of HM-1 and HM-2. Removal of endothelium of the coronary artery led to decreases in the vasorelaxant effects of HM-1, HM-7 but not HM-2, HM-3, HM-4 and HM-5. Our results showed that xanthones isolated from Halenia elliptica are vasoactive substances which exhibit either endothelium-dependent or endothelium-independent mechanisms in rat coronary artery. The potency and mechanism(s) of the vasorelaxant effects of these xanthones may be relevant to the structure–activity differences in the level and the position of the substituent groups with the primary xanthone structure. 相似文献
4.
Yan Wang Jian-Gong Shi Mu-Zou Wang Chun-Tao Che John H.K. Yeung 《Phytomedicine》2009,16(12):1144-1150
In this study, six major xanthones, isolated and identified from Halenia elliptica were investigated for their vasodilatory actions in isolated rat coronary artery. The xanthones, including 1-hydroxy-2,3,5-trimethoxy-xanthone (HM-1), 1-hydroxy-2,3,4,7-tetramethoxy-xanthone (HM-2), 1-hydroxy-2,3,4,5-tetramethoxy-xanthone (HM-3), 1,7-dihydroxy–2,3,4,5-tetramethoxy-xanthone (HM-4), 1,5-dihydroxy-2,3-dimethoxy-xanthone (HM-5) and 1,7-dihydroxy-2,3-dimethoxy-xanthone (HM-7) caused vasodilation in the coronary artery pre-contracted with 1 μM 5-hydroxytryptamine (5-HT), with EC50 values ranging from 1.4±0.1 μM (HM-1) to 6.6±1.4 μM (HM-2). The EC50 values of the other xanthones were between those of HM-1 and HM-2. Removal of endothelium of the coronary artery led to decreases in the vasorelaxant effects of HM-1, HM-7 but not HM-2, HM-3, HM-4 and HM-5. Our results showed that xanthones isolated from Halenia elliptica are vasoactive substances which exhibit either endothelium-dependent or endothelium-independent mechanisms in rat coronary artery. The potency and mechanism(s) of the vasorelaxant effects of these xanthones may be relevant to the structure–activity differences in the level and the position of the substituent groups with the primary xanthone structure. 相似文献
5.
Singh O Ali M Akhtar N 《Zeitschrift für Naturforschung. C, Journal of biosciences》2011,66(1-2):17-23
Phytochemical investigations of the ethanolic extract of the seeds of Rhus coriaria L. (Anacardiaceae) led to the identification of four new xanthones, characterized as 2,3-dihydroxy-7-methyl xanthone (1), 2,3,6-trihydroxy-7-hydroxymethylene xanthone-1-carboxylic acid (2), 2-methoxy-4-hydroxy-7-methyl-3-O-beta-D-glucopyranosyl xanthone-1,8-dicarboxylic acid (4), and 2-hydroxy-7-hydroxymethylene xanthone-1,8-dicarboxylic acid 3-O-beta-D-glucopyranosyl-(2'-->3")-3"-O-stigmast-5-ene (5), along with the known steroidal glucoside beta-sitosterol-beta-D-glucoside (3). The structures of the isolated compounds have been identified on the basis of spectral data analysis and chemical reactions. All xanthones were active against Aspergillus flavus. 相似文献
6.
Seven 1-hydroxyxanthones have been isolated from the roots of Frasera albomarginata. There were 1-hydroxy-3,7-dimethoxy-, 1-hydroxy-3,5-dimethoxy-, 1,8-dihydroxy-3,5-dimethoxy-, 1-hydroxy-2,3,4,7-tetramethoxy-, 1-hydroxy-2,3,4,5-tetramethoxy-, 1-hydroxy-3,4,7-trimethoxy- and 1-hydroxy-2,3,5-trimethoxyxanthone. Six 1-hydroxyxanthones were obtained from the roots of F. speciosa. These were 1-hydroxy-2,3,4,5-tetramethoxy-, 1-hydroxy-2,3,4,7-tetramethoxy-, 1-hydroxy-2,3,5-trimethoxy-, 1,7-dihydroxy-2,3,4-trimethoxy-, 1,7-dihydroxy-2,3-dimethoxy- and 1,3-dihydroxy-4,5-dimethoxyxanthone. 相似文献
7.
《Biochemical Systematics and Ecology》2004,32(10):861-866
Diverse biological characters commonly vary with altitude in species that have a wide altitudinal distribution, partly at least as a result of adaptation to differences in aridity, but whether such variation exists for phytochemical constituents remains unknown. Therefore, levels of seven important phytochemical constituents of Swertia franchetiana (swertiamarin, oleanolic acid, swertisin, mangiferin, 1,5,8-trihydroxy-3-methoxyxanthone, 1,8-dihydroxy-3,7-dimethoxyxanthone and 1,8-dihydroxy-3,5-dimethoxyxanthone) were studied and statistically compared, using materials collected from sites ranging from 2200 to 3960 m in altitude. Swertiamarin was the most abundant in all samples, then mangiferin, oleanolic acid and the other three xanthones. Throughout the distributional range of this species, no altitudinal trend was detected for other constituents except 1,8-dihydroxy-3,7-dimethoxyxanthone, which showed a negative correlation with altitude. However, the concentration of 1,8-dihydroxy-3,7-dimethoxyxanthone and mangiferin showed a significantly latitudinal and longitudinal correlation. 相似文献
8.
A new xanthone and twelve known compounds were isolated from the aerial parts of Gentiana corymbifera. The new xanthone was shown to be 3-methylcorymbiferin (1,8-dihydroxy-3,4,5-trimethoxy-9H-xanthen-9-one) by spectral and chemical procedures. The chemotaxonomic implications are discussed. 相似文献
9.
Two new xanthones isolated from Lawsonia inermis have been characterised as 1, 3-dihydroxy-6, 7-dimethoxyxanthone and 1-hydroxy-3, 6-diacetoxy-7-methoxyxanthone and named laxanthone-I and II, respectively. 相似文献
10.
T. Hanumaiah B.K. Rao C.P. Rao G.S.R. Rao J.U.M. Rao K.V.J. Rao David S. Marshall Ronald H. Thomson 《Phytochemistry》1985,24(8):1811-1815
Two new naphthalene derivatives and three naphthoquinones have been found in the root bark of Ventilago maderaspatana. Their structures are 2-acetyl-6,7-dimethoxy-3-methyl-1,8-methylenedioxynaphthalene (ventilaginone) and 1,3-dihydro-6,9-dihydroxy-7,8-dimethoxy-1-methylnaphtho[2,3-c]furan-3-one (ventilagol), 2(2′-acetoxypropyl)-3-hydroxy-5,7,8-trimethoxy-1,4-naphthoquinone (maderone), cordeauxione and isocordeauxione. The root bark of V. calyculata contains 2-methoxystypandrone and 1-hydroxy-6-methoxy-3-methylxanthone-8-carboxylic acid (calyxanthone). 相似文献
11.
Cell-suspension cultures of Centaurium erythraea and Centaurium littorale (Gentianaceae) respond to methyl jasmonate and yeast extract with a differential accumulation of xanthones. Methyl jasmonate induced the formation of 1-hydroxy-3,5,6,7-tetramethoxyxanthone, the amount of which increased in both cell cultures around 10 h after addition. A substantial increase in the activity of phenylalanine ammonia-lyase (PAL) was not observed. When challenged with yeast extract the cell cultures accumulated l,5-dihydroxy-3-methoxyxanthone. This appeared rapidly after addition of yeast extract in C. erythraea but its amount in C. littorale increased only after a lag phase of 25 h. While PAL activity in C. erythraea was strongly suppressed a fourfold increase in its activity was found in C. littorale. Both elicited xanthones accumulated intracellularly. A scheme for xanthone biosynthesis in the two cell cultures is proposed. 相似文献
12.
Wanderley G. De Oliveira Antonio A. Lins Mesquita Roberto A. De Lima Otto R. Gotllieb Hugo E. Gotllieb 《Phytochemistry》1984,23(10):2390-2391
The trunk wood of Tovomita excelsa (Guttiferae) from north-eastern Brazil contains, besides betulinic acid, 1,5-dihydroxy-6-methoxyxanthone, 1,6-dihydroxy-5-methoxyxanthone, 5,6-dihydroxy-1-methoxyxanthone and 1,7- dihydroxy-6-methoxyxanthone. 相似文献
13.
Phytochemical investigation of Gentianella turkestanorum (Gentianaceae) afforded nineteen compounds, including six xanthones (1–6), two triterpenoids (7–8), eight flavones (9–16) and three iridoids (17–19). Here, we firstly reported that 1-hydroxy-3,5-dimethoxyxanthone (4), 1, 8-dihydroxy-3-methoxyxanthone (5), apigenin (9), quercetin (10), luteolin-7-O-glucoside (12) and three other compounds (1, 8-dihydroxy-3-methoxyxanthone (5), apigenin-7-O-gluco (1″ → 3‴) glucoside (15) and luteolin-7-O-gluco (1″ → 3‴) glucoside (16)) could be isolated from G. turkestanorum. The occurrence of chemical data and the sequence data might be employed as common constituents of the genera Gentianella, Lomatogonium and Swertia. 相似文献
14.
Zuo Peng Li Yeong Hun Song Zia Uddin Yan Wang Ki Hun Park 《Bioorganic & medicinal chemistry》2018,26(3):737-746
Cratoxylum cochinchinense displayed significant inhibition against protein tyrosine phosphatase 1B (PTP1B) and α-glucosidase, both of which are key target enzymes to attenuate diabetes and obesity. The compounds responsible for both enzymes inhibition were identified as twelve xanthones (1–12) among which compounds 1 and 2 were found to be new ones. All of them simultaneously inhibited PTP1B with IC50s of (2.4–52.5?µM), and α-glucosidase with IC50 values of (1.7–72.7?µM), respectively. Cratoxanthone A (3) and γ-mangostin (7) were estimated to be most active inhibitors against both PTP1B (IC50?=?2.4?µM for 3, 2.8?µM for 7) and α-glucosidase (IC50?=?4.8?µM for 3, 1.7?µM for 7). In kinetic studies, all isolated xanthones emerged to be mixed inhibitors of α-glucosidase, whereas they behaved as competitive inhibitors of PTP1B. In time dependent experiments, compound 3 showed isomerization inhibitory behavior with following kinetic parameters: Kiapp?=?2.4?µM; k5?=?0.05001?µM?1?S?1 and k6?=?0.02076?µM?1?S?1. 相似文献
15.
Crude terpenoid fractions from stele tissues of Gossypium barbadense infected with Verticillium dahliae contained two prominent compounds that were nonaldehydic, but readily autooxidized to the terpenoid aldehydes hemigossypol and 6-methoxyhemigossypol. Spectral analyses, chemical studies, and comparisons with model compounds showed that these compounds were the sesquiterpenoids 3,4-dihydroxy-5-isopropy]-7-methy]-2H-naphtho[1,8-bc]furan (1a) and 3-hydroxy-5-isopropyl-4-methoxy-7-methyl-2H-naphtho[1,8-bc]furan (1b). The trivial names desoxyhemigossypol and desoxy-6-methoxyhemigossypol are proposed for (1a) and (1b). The sesquiterpenoid, previously isolated and named vergosin, is apparently desoxy-6-methoxyhemigossypol. 相似文献
16.
Six xanthones, 1,3,7-trihydroxy-2-(2-hydroxy-3-methyl-3-butenyl)-xanthone (1), 1,7-dihydroxy-2,3-[2'-(1-hydroxy-1-methylethyl)-dihydrofurano]-xanthone (2), 1,3,7-trihydroxy-5-methoxyxanthone (3), 1,7-dihydroxy-5,6-dimethoxyxanthone (4), 4,5-dihydroxy-2,3-dimethoxyxanthone (5), 1,3-dihydroxy-2,4-dimethoxyxanthone (6) and 21 known xanthones were isolated from the leaves and stems of Hypericum chinense. Their structures were established based on spectroscopic studies. 相似文献
17.
Navneet Kishore Bhuwan B. Mishra Vinod K. Tiwari Vyasji Tripathi 《Phytochemistry letters》2010,3(2):62-65
The naphthoquinones, lapachol (1), plumbagin (2), 2-isopropenyl-9-methoxy-1,8-di-oxa-dicyclopenta[b,g]naphthalene-4,10-dione (3), 9-hydroxy-2-isopropenyl-1,8-dioxa-dicyclopenta[b,g]naphthalene-4,10-dione (4), 2-(1-hydroxy-1-methyl-ethyl)-9-methoxy-1,8-dioxa-dicyclopenta[b,g]naphthalene-4,10-dione (5) and 5,7-dihydroxy-8-methoxy-2-methyl-1,4-naphthoquinone (6) were isolated isolated from roots of Plumbago zeylanica. The new constituents (3–5) in addition to known compounds (1, 2 and 6) were characterized by spectral analysis (UV, IR, 1D & 2D NMR and MS). 相似文献
18.
Takenaka Y Tanahashi T Nagakura N Hamada N 《Zeitschrift für Naturforschung. C, Journal of biosciences》2000,55(11-12):910-914
From the cultures of the spore-derived mycobionts of the lichen Pyrenula japonica, two new xanthones, 1,8-dihydroxy-3-hydroxymethyl-5-methoxyxanthone and 1,2,8-trihydroxy-5-methoxy-3-methylxanthone, were isolated along with 1,7-dihydroxy-3-methylxanthone, 1,5,8-trihydroxy-3-methylxanthone, 1,8-dihydroxy-5-methoxy-3-methylxanthone, emodin and sclerotiorin. Their structures were determined by spectroscopic methods. Sclerotiorin was isolated for the first time from lichen mycobionts. Radical scavenging activities of the isolated xanthones were also studied. 相似文献
19.
Two new diterpenes, 3α-angeloyloxy-18-hydroxy-13-furyl-ent-labda-8(17)-ene and 3α-hydroxy-18-angeloyloxy- 13-furyl-ent-labda-8(17)-ene and an only recently reported third diterpene, 3α, 18-dihydroxy-13-furyl-ent-labda-8(17)-ene, were isolated from the leaves of Gutierrezia grandis. Their structures were determined by mass spectral, IR, 1H NMR and 13C NMR data was well as chemical evidence. 相似文献
20.
A.A. Leslie Gunatilaka A.M.Y. Jasmin De Silva Subramaniam Sotheeswaran 《Phytochemistry》1982,21(7):1751-1753
2-Hydroxyxanthone, 1,7-dihydroxyxanthone, 1-hydroxy-7-methoxyxanthone, 6,7-dimethoxy-1-hydroxyxanthone and a new natural product, 2-hydroxy-3-methoxyxanthone, have been isolated and characterized from the phenolic fraction of the chloroform extract of the timber of Hypericum mysorense. The presence of simple xanthones in this genus supports the classification of Hypericum in the subfamily Hypericoideae in Guttiferae. 相似文献