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1.
From the aerial parts of the Myrica gale catechin, epicatechin, gallocatechin, epigallocatechin, epigallocatechin-3-O-gallate, gallocatechin-(4 alpha-8)-epicatechin, gallocatechin-(4 alpha-8)-epigallocatechin, and gallocatechin-(4 alpha-8)-gallocatechin-(4 alpha-8)-gallocatechin (1), were isolated. The 1H- and 13C-NMR data of the peracetate derivative of the trimer are reported.  相似文献   

2.
A polysaccharide, a glucan with mean M(r) of 1.0 x 10(6) (MP1), was isolated from the mesocarp of fruits of Orbignya phalerata. Chemical and spectroscopic studies indicated that MP1 has a highly branched glucan type structure composed of alpha-(1-->4) linked D-glucopyranose residues with (3-->4), (4-->6), and with (3-->6) branching points. MP1 enhanced phagocytosis in vivo and exhibited anti-inflammatory activity.  相似文献   

3.
Two polysaccharides with mean M(r)s of 2.0 x 10(6) and 3.75 x 10(5), were isolated from powdered seeds of Centrosema pubescens by fractionation on Sephacryl S-300 HR. Chemical and spectroscopic studies indicated that they have a backbone chain composed of beta-(1-->4)-linked D-galactopyranose residues having branches composed of alpha-(1-->5)-linked L-arabinofuranose residues at position 6 of D-galactose of the backbone chain. The polysaccharides showed reticuloendothelial system-potentiating activity in a carbon clearance test.  相似文献   

4.
利用天然可再生资源没食子酸(GA)与氢化萜烯基环氧树脂(HTME)在一定条件下反应制备了环氧树脂基多元醇(HTME - GA多元醇).通过研究合成反应的影响因素,确定了HTME - GA多元醇的合成反应条件:以GA物质的量12.5倍的正丙醇为反应溶剂,以占HTME与GA总质量2%的季铵盐为催化剂,HTME与GA共沸回流反应3h.经FT - IR、NMR光谱表征了HTME - GA多元醇的化学结构,比较了该多元醇与聚己二异氰酸酯HN90T、改性聚己二异氰酸酯EC385的交联反应特性及交联产物性能.实验结果表明,HTME - GA多元醇与EC385的交联产物具有优良的机械力学性能,与HN90T的交联产物具有较好的耐液体介质性能和硬度,但后者柔韧性较差.随着NCO与OH物质的量比的增大,交联产物的硬度和耐液体介质性能提高.  相似文献   

5.
A new resveratrol trimer, malaysianol A (1), five known resveratrol oligomers: laevifonol (2), ampelopsin E (3), α-viniferin (4), ε-viniferin (5), diptoindonesin A (6), and bergenin (7) have been isolated from the acetone extract of the stem bark of Dryobalanops aromatica by combination of vacuum and radial chromatography techniques. Their structures were established on the basis of their spectroscopic evidence and comparison with the published data. The cytotoxic activity of the compounds was tested against several cell lines in which compound 4 was found to inhibit strongly the growth of HL-60 cell line.  相似文献   

6.
吕金顺 《林业科学》2007,43(3):122-126
沙枣(Elaeagnus angustifolia)也叫银柳、香柳、桂香柳,与沙棘同属胡颓子科,常绿灌木,主产于西北地区,分布在新疆、甘肃、青海、内蒙古西部等与沙漠接壤的典型大漠干旱或戈壁滩上.其树皮、果实和花均可用于治疗风寒咳嗽、痢疾腹泻等疾病(江苏新医学院中药大辞典编写组,1977).  相似文献   

7.
Triterpenes from the resin of Protium heptaphyllum.   总被引:2,自引:0,他引:2  
From the neutral fraction of the resin of Protium heptaphyllum, a mixture of alpha- and beta-amyrin, a mixture of maniladiol and brein have been isolated as main components, and the novel 3 beta,24-dihydroxy-urs-12-ene (1), 3-oxo-20S-hydroxytaraxastane (2) and 3 beta,20S-dihydroxytaraxastane (3) as minor components. NMR data of the last three compounds are provided.  相似文献   

8.
Summary The reaction of ferric chloride with the lignin model guaiacol affords primarily a complex mixture of coupled guaiacol oligomers. Major components were the symmetrical carbon-carbon coupled dimer 3,3-dimethoxy-[1,1-biphenyl]-4,4diol and the trimer 3,3,5-trimethoxy-[1,1:3,1-terphenyl]-4,4,4-triol which were isolated by preparative HPLC and characterized by 1HNMR spectroscopy and mass spectrometry. An unstable component believed to be a 4,4-diphenoquinone derived from the trimer was also prominent. The reaction of chromium trioxide with guaiacol yields the same dimer, trimer and diphenoquinone as well as 2-methoxy-p-benzoquinone. The major product with chromium trioxide, however, is an inert, highly insoluble polymer which was shown by degradation to contain guaiacol oligomers bound or crosslinked by hydroxylated chromium species. Magnetic susceptibility measurements clearly indicated that the valency of chromium in the polymer was + 3. It is postulated that similar complexes formed from phenolic lignin units are responsible for the weather resistance of chromium trioxide treated wood surfaces. In a broader context this study is relevant to the fixation of hexavalent chromium from a range of widely used wood preservative formulations.The authors wish to thank the following: Tom Syers (CSIRO Division of Forest Products) for technical assistance, Mary Reilly (CSIRO Division of Forest Products) for NMR spectral determinations and Ivan Vit (CSIRO Division of Chemicals and Polymers) for mass spectral determinations  相似文献   

9.
Li W  Huang X  Yang XW 《Fitoterapia》2012,83(2):318-322
Three new sesquiterpenoids, 1α-(3″-ethyl-cis-crotonoyloxy)-8-angeloyloxy-3β,4β-epoxy-bisabola-7(14),10-diene (1), 7β-angeloyloxy-14-hydroxy-notonipetranone (2) and 1α-hydroxy-7β-(4-methylsenecioyloxy)-oplopa-3(14)Z,8(10)-dien-2-one (3) were isolated from ethanolic extract of the dried flower buds of Tussilago farfara L., along with nine known sesquiterpenoids (4-12). All of these compounds were evaluated for their effect on the inhibition of nitric oxide (NO) production induced by lipopolysaccharide in macrophage cell line RAW 264.7 and exhibited inhibitory activity on NO production in a dose-dependent manner. 7β-(4-Methylsenecioyloxy)-oplopa-3(14)E,8(10)-dien-2-one (8) was proved to be the best among these tested sesquiterpenoids with an IC(50) value of 10.80 μM.  相似文献   

10.
Liu XG  Gao PY  Wang GS  Song SJ  Li LZ  Li X  Yao XS  Zhang ZX 《Fitoterapia》2012,83(3):599-603
Antidepressant activity-guided fractionation of the MeOH extract of Valeriana fauriei Briq. roots resulted in the isolation of two new germacrane-type sesquiterpenes (1-2) in addition to seven known ones (3-9). Their structures were elucidated as 1β,10α-dihydroxyl-8α-acetoxyl-10β,11,11-trimethyl-4-formyl-bicyclogermacren-E-4(5)-ene (1), 1β-hydroxyl-8α-acetoxyl-11,11-dimethyl-4-formyl-bicyclogermacren-E-4(5),10(14)-diene (2), bicyclo[8,1,0]5β-hydroxyl-7β-1acetoxyl-5α,11,11'-trimethyl -E-1(10)-ene-4α,15-olide (3), 8α-acetoxyl-3α,4α,10-trihydroxyl-guaia-1(2)-ene-12,6α-olide (4), 2-Ethylhexyl-4-hydroxybenzoate (5), 11αH-gemacra-1(10)E,4Z-diene-3-one-12,6α-olide (6), β-Sitoterol (7), isovaleric acid (8), isoborneol acetate (9), using a combination of UV, IR, mass spectroscopy, 1D and 2D NMR spectroscopy. The antidepressant activity of compounds 1-4 was investigated by the FST on mice. Among them, compounds 3 and 4 showed the significant antidepressant activity (*, P<0.01).  相似文献   

11.
J. Bicker  F. Petereit  A. Hensel   《Fitoterapia》2009,80(8):483-495
From the ethyl acetate soluble fraction of an acetone–water extract of the aerial parts of Rumex acetosa L. (Polygonaceae), a variety of monomeric flavan-3-ols (catechin, epicatechin, epicatechin-3-O-gallate), A- and B-type procyanidins and propelargonidins (15 dimers, 7 trimers, 2 tetramers) were isolated with 5 so far unknown natural products. Dimers: procyanidin B1, B2, B3, B4, B5, B7, A2, epiafzelechin-(4β→8)-epicatechin, epiafzelechin-(4β→8)-epicatechin-3-O-gallate (new natural product), epiafzelechin-(4β→6)-epicatechin-3-O-gallate (new natural product), epiafzelechin-3-O-gallate-(4β→8)-epicatechin-3-O-gallate, B2-3′-O-gallate, B2-3,3′-di-O-gallate, B5-3′-O-gallate, and B5-3,3′-di-O-gallate. Trimers: procyanidin C1, epiafzelechin-(4β→8)-epicatechin-(4β→8)-epicatechin (new natural product), epicatechin-(4β→8)-epicatechin-(4β→8)-catechin, cinnamtannin B1, cinnamtannin B1-3-O-gallate (new natural product), tentatively epicatechin-(2β→7, 4β→8)-epiafzelechin-(4α→8)-epicatechin (new natural product), and epicatechin-3-O-gallate-(4β→8)-epicatechin-3-O-gallate-(4β→8)-epicatechin-3-O-gallate.Tetramers: procyanidin D1 and parameritannin A1. All compounds were elucidated by ESI-MS, CD spectra, 1D- and 2D-NMR experiments as free phenols or peracetylated derivatives and, in part, after partial acid-catalysed degradation with phloroglucinol.A more abundant proanthocyanidin polymer was also isolated, purified and its chemical composition studied by 13C NMR.In addition a so far unknown phloroglucinolglycoside (1-O-β-d-(2,4-dihydroxy-6-methoxyphenyl)-6-O-(4-hydroxy-3,5-dimethoxybenzoyl)-glucopyranoside) was isolated.  相似文献   

12.
Koubaa I  Damak M 《Fitoterapia》2003,74(1-2):18-22
A new dilignan, 7,8-trans-7',8'-trans-7",8"-cis-7"',8"'-cis-8,8'-trans-4",4"',7',9,9",9"'-hexahydroxy-3,3',3",3"'-tetramethoxy-4,8":4',8"':5,7":5',7"'-tetraoxy-7,9'-epoxy-8,8'-dilignan-7'-ol, named cynarinine (2), was isolated together with the known tracheloside (1) from the seeds of Cynara cardunculus.  相似文献   

13.
Two new coumarins, 7-methoxy-5-prenylcoumarin (isocedrelopsin) (1) and 3',4'-dihydrobraylin (2), were isolated from the trunk bark of Cedrelopsis grevei, along with five known coumarins, microfolicoumarin (6,7-dimethoxy-5-prenylcoumarin, (3), obliquin (4), 8-methoxyobliquin (5), aesculetin (6), cedrelopsin (7) and scoparone (8).  相似文献   

14.
Four known lactones were isolated from Tithonia diversifolia: furanoheliangolides 1,3-dihydroxy-3,10-epoxy-8-(-2-methylpropanoyloxy)-germacra-11(13)-ene-6,12-olide (1), 1,3-dihydroxy-3,10-epoxy-8-(2-methylpropanoyloxy)-germacra-4,11(13)-diene-6,12-olide (2), 1,3-dimethoxy-3,10-epoxy-8-(2-methylpropanoyloxy)-germacra-4,11(13)-diene-6,12-olide (3) and, observed in natural source for the first time, furanoheliangolide 1-hydroxy-3-methoxy-3,10-epoxy-8-(2-methylpropanoyloxy)-germacra-4,11(13)-diene-6,12-olide (4). The activity of sesquiterpene lactones on superoxide anion (O(2)(o)(-)) generation from PMA-activated neutrophils was evaluated. Compound 1 did not show a full dose dependent behavior. The IC(100) was 8+/-1, 12+/-1, and 17+/-3 microM for 2 to 4, respectively.  相似文献   

15.
Liang N  Tang Y  Okuda T 《Tree physiology》2001,21(14):1047-1055
Cuttings of the southeast Asian tropical rain forest tree species, Pongamia pinnata (L.) Pierre were raised in growth chambers providing a photosynthetic photon flux density (PPFD) of 60 micromol m(-2) s(-1) with either a low or a high red:far-red light ratio (LR and HR, repectively). The chambers were supplied with air containing CO(2) at a concentration of either 400 (LR4 and HR4, respectively) or 800 micromol mol(-1) (HR8 and LR8, respectively). After 4 months, leaf morphology and photosynthetic characteristics were determined. Relative to HR4, the LR4 treatment increased leaf area and total chlorophyll concentration (Chl) by 24 and 25%, respectively, but reduced leaf mass per unit area (LMA) by 19%. Elevated [CO(2)] significantly increased leaf area and LMA but did not affect Chl of LR or HR plants. Leaf nitrogen concentration was unaffected by the red:far-red light ratio but decreased significantly in seedlings in the elevated [CO(2)] treatment. Photosynthesis measured in situ under the growth conditions of ambient light and [CO(2)] (A(amb)) was 30% lower on an area basis and 14% lower on a mass basis in LR4 plants than in HR4 plants. Elevated [CO(2)] reduced the activity of ribulose-1,5-bisphosphate carboxylase/oxygenase and thus decreased light-saturated photosynthetic rate in both HR and LR plants. Elevated [CO(2)] increased mean leaf area and decreased respiration rates in both LR and HR plants. The LR8 plants had significantly higher A(amb) than LR4 plants, but similar A(amb) to HR8 plants.  相似文献   

16.
Prasad D 《Fitoterapia》2000,71(3):245-253
Two A-type proanthocyanidins, ent-epiafzelechin-(4alpha-->8, 2alpha-->O-->7)-(-)-epicatechin and its isomer, ent-epiafzelechin-(4alpha-->8', 2alpha-->O-->7')-catechin, together with other known compounds, have been isolated from the roots of Prunus armeniaca. The concerted use of one- and two-dimensional NMR methods (1H-(1)H COSY, HMQC, HMBC and NOESY) allowed the identification of these compounds.  相似文献   

17.
We investigated the effects of root medium pH on water transport in whole-plant and detached roots of paper birch (Betula papyrifera Marsh.). Exposure of seedling roots to pH 4 and 8 significantly decreased root hydraulic conductivity (Lp) and stomatal conductance (gs), compared with pH 6. When roots of solution-culture-grown (pH 6) seedlings were transferred to pH 4 or 8, their steady-state water flow (Qv) declined within minutes, followed by a decline in gs. The root oxygen uptake rates were not significantly affected by the pH treatments. Treatment of roots with mercuric chloride resulted in a large decrease in Qv at pH 6; the extent of this decrease was similar to that brought about by pH 4 and 8. Lowering root temperature from 21 to 4 degrees C decreased Qv irrespective of medium pH. Low root temperatures did not offset the effects of medium pH 4 on Qv and the roots in this treatment had a high activation energy for water flow. Conversely, roots exposed to pH 8 had a low activation energy, similar to that at pH 6. When 2 micro M abscisic acid, (+/-)-cis-trans-ABA, was added to the root medium, Qv increased in roots that were incubated at pH 6. It also increased slightly in roots incubated at pH 4, but not at pH 8. The increase at pH 4 and 6 was temperature-dependent, occurring at 21 degrees C, but not 4 degrees C. We suggest that the pH treatments are responsible for altering root water flow properties through their effects on the activity of water channels. These results support the concept that ABA effects on water channels are modulated by other, possibly metabolic- and pH-dependent factors.  相似文献   

18.
XW Yang  MZ Huang  YS Jin  LN Sun  Y Song  HS Chen 《Fitoterapia》2012,83(7):1169-1175
A new chlorinated flavonoid, 3, 6, 8-trichloro-5, 7, 3', 4'-tetrahydroxyflavone (1), a new biscoumaric acid derivative, 4-O-(2″, 3″-O-diacetyl-6″-O-p-coumaroyl-β-d-glucopyranosyl)-p-coumaric acid (2), and 8, 3', 4'-trihydroxyflavone-7-O-β-d-glucopyranoside (3) together with twenty-four known compounds (4-27) were isolated from the whole plant of Bidens bipinnata. All chemical structures were established on the basis of UV-, MS- and NMR ((1)H, (13)C, (1)H-(1)H COSY, HMQC and HMBC) spectroscopic data. Some of the isolated compounds were tested for the inhibition of α-amylase. The result showed that isookanin (6) was a potent inhibitor of α-amylase (IC(50)=0.447mg/ml).  相似文献   

19.
Li X  Luo JG  Wang XB  Luo J  Wang JS  Kong LY 《Fitoterapia》2012,83(5):883-887
Two new compounds, a neolignan (1), and a benzofuran derivative (2), along with 6 known compounds (3-8), were isolated from the aerial parts of Leontopodium leontopodioides. The structures of the new compounds were elucidated as (7R,8S)-3,5'-dimethoxy-4',7-epoxy-8,3'-neolignane-5,9,9'-triol (1) and (2R)-12-hydoxy-4-methoxy-tremeton (2) on the basis of their spectroscopic data, respectively. All of the isolates were evaluated for their effects on the inhibition of nitric oxide (NO) production in lipopolysaccharide-activated RAW264.7 macrophages and compounds 1 and 8 exhibited inhibitory activity with IC(50) values of 35.80 and 24.41 μM, respectively.  相似文献   

20.
The new cerebroside 1-O-(β-d-glucopyranosyl)-(2 S, 3 S, 4R, 8E)-2-[(2′R)-2′-hydroxytetracosenoilamino]-8-octadecene-1,3,4-triol (1) and ceramide (2 S, 3 S, 4R, 8E)-2-[(2′R)-2′-hydroxytetracosenoilamino]-8-octadecene-1,3,4-triol (2) were isolated from the ethyl acetate extract of the pollen of Brassica napus L. The structures of 1 and 2 were elucidated on the basis of chemical and spectroscopic method. Two new compounds were evaluated for activity in vitro assays for the cytotoxic activities against human tongue squamous carcinoma cell line (Tca8113).  相似文献   

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