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1.
A novel triterpene 1 (3-β-hydroxy-fern-7-en-6-one-acetate) together with four known compounds, urs-12-en-11-one-3-acetyl (2), 3-β-hydroxy-fern-8-en-7-one-acetate (3), olean-12-en-11-one-3-acetyl (4) and leucodin (5) were obtained from the S. latifolia roots. All compounds were isolated from the n-hexane extract of S. latifolia roots using several chromatographic techniques. The structure of the isolated compounds was elucidated on the basis of (1)H-NMR, (13)C-NMR and 2D NMR data (HMBC, HMQC, COSY, TOCSY, NOESY, DEPT) as well as GC EITOF-HRMS.  相似文献   

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From the subaerial parts of S. tomentosa L. (Asteraceae), two new dihydroisocoumarins, compounds 1 and 2 , a new phthalide, 3 , and a new stilbene derivative, 4 , were isolated, together with four known compounds, (±)‐hydrangenol ( 5 ), (?)‐hydrangenol 4′‐O‐β‐glucoside ( 6 ), (±)‐hydramacrophyllol A ( 7 ), and (±)‐hydramacrophyllol B ( 8 ). All secondary metabolites were identified on the basis of physicochemical, spectroscopic, and mass‐spectrometric data. The known compounds 5 – 8 were isolated for the first time from this species.  相似文献   

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A new coumadn was obtained from the stems and roots of Wikstroemia indica (L.) C.A.Mey.Its structure was elucidated as methyl 3-(2-hydroxy-4-(7-hydroxy-6-methoxy-2-oxo-2H-chromen-3-yloxy) phenyl) propanoate by spectroscopic methods.  相似文献   

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A chromatographically inseparable crystalline mixture of the previously undescribed quercetin-4′-O-β-galactopyranoside and the known quercetin-3-O-β-glucopyranoside (isoquercitrin) in a 7:5 ratio was isolated from the extract of the aerial part of Filipendula ulmaria (L.) Maxim. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 122–124, March–April, 2006.  相似文献   

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From the ethanolic extract of the whole plant of Anaphalis aureo-punctata, a new acylated flavonoid glycoside 3-O-kaempferol-3-O-acetyl-6-O-(p-coumaroyl)-β-D-glucopyranoside (1), and five known phenolic compounds 3-O-kaempferol-6- O- ( p-coumaroyl )-β-D-glucopyranoside ( 2 ), kaempferol-3- O-β-D-glucopyranoside 3,6-(4′-hydroxystyryl)-4-methoxy-2-pyrone (4), 2H-pyran-2-one, 6-[ 2-( 4-(β-D-glucopyranosyloxy ) phenyl ) ethenyl ]-4-methoxy-( E ) (5) and 4-hydroxy-3-methoxycinnamic hexacosyl ester (6) were isolated. Their structures were established by spectral methods (UV, IR, MS, 1D, 2D-NMR). The flavonoid glycosides, 1, 2 and 3 showed markedly inhibited oxidative DNA strand breaks induced by Fenton reaction and NADH/PMS in a concentration-dependent manner.  相似文献   

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The wood of Anodendron paniculatum contains a large number of cardenolides; 14 of such compounds could be spottet in PC. and TLC. with Kedde reagent. Five of these (A, E 1, E 2, F, and G) could be isolated in crystalline form and two other ones (B 1 and B 2) as an amorphous mixture. A crystalline aromatic ketone (compound α) was obtained as by-product. The isolated cardenolides, named as anodendrosides A-G, were found to be glycosides containing unusual sugars. According to UV. and IR. spectra the genin portion in anodendroside E 1 (probably also in F and B 2) contains a cardenolide structure with saturated ring D and normal butenolide side-chain, while the anodendrosides A, E 2 and G (probably also B 1) contain an additional double bond at C-16. The four compounds for which IR. spectra could be taken (A, E 1, E 2, and G) possess a keto group.  相似文献   

10.
北苍术和茅苍术挥发油成分的比较   总被引:1,自引:0,他引:1  
采用气相色谱-质谱联用技术分析了北苍术和茅苍术的挥发油成分,分别鉴定出47和50种化学成分,并测定了其相对含量。 采用色谱指纹图谱八强峰法和分区法,根据色谱峰的保留时间把总离子流色谱图分为5个区,比较了北苍术和茅苍术的挥发油成分。 结果表明,在总离子流色谱图Ⅳ和Ⅴ区中,从北苍术和茅苍术中均检出苍术的主要药效成分β-桉叶油醇、苍术酮和苍术素,且相对含量较高。 这表明《中国药典》将北苍术、茅苍术统称为苍术具有一定的科学性。  相似文献   

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In this paper, the study of antioxidant activity and phenolic composition of three different extracts (EtOAc, n-BuOH and H(2)O) of field horsetail (Equisetum arvense L.) is presented. The antioxidant activity has been evaluated measuring the total reducing power (expressed by Ascorbate Equivalent Antioxidant Capacity - AEAC), inhibition of lipid peroxidation, and free radical scavenging capacity (RSC) towards 2,2-diphenyl-1-picrylhydrazyl (DPPH radical) and nitric oxide (NO), respectively. In addition, the total flavonoid content (TFC) and phenolic constituents of each extract have been determined. The results obtained show that the highest RSC regarding both DPPH and NO radicals is expressed by EtOAc extract (EC(50)=2.37 microg/mL and EC(50)=90.07 microg/mL, respectively), and the lowest by H(2)O extract (EC(50)=37.2 microg/mL and EC(50)>333.33 microg/mL, respectively). n-BuOH extract showed the highest total reducing power (AEAC=13.40 microg/mL). Differences in the phenolic composition of examined extracts are found comparing the HPLC chemical profiles. Although, isoquercitrin is the main flavonoid in both EtOAc and n-BuOH extracts, a considerable amount of di-E-caffeoyl-meso-tartaric acid was presented in the n-BuOH extract. In H(2)O extract high content of phenolic acids and low percentage of flavonoids were detected.  相似文献   

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Abstract

Rhaponticum acaule (L.) DC. is a medicinal plant commonly used for the treatment of some illnesses such as gastrointestinal infections. In this work, we report the composition of different parts of this plant on phenolic compounds, their quantification, and antioxidant activity. The obtained results reported that methanolic extracts of the three parts studied revealed high phenolic contents. For flavonoid contents, the highest contents were reported in organic extracts of leaf part. In addition, results obtained from the study of the antioxidant activity showed that methanolic extract of root presented the highest activity, in DPPH? scavenging ability test with an IC50 of 0.31?±?0.04?mg/mL and in FRAP test with an EC50 of 1.06?±?0.02?mg/mL. The RP-HPLC-PDA analysis revealed the presence of five phenolic acids (sinapic, caffeic, chlorogenic, ferulic and syringic acids), one flavanone (naringenin), one flavonol (rutin) and vanillin.  相似文献   

15.
For several millennia, leaves of Echium amoenum Fisch. & C. A. Mey., an important Iranian medicinal plant with nutritional value as nutraceutical, have been used as tea for the treatment of several conditions, including inflammation. The nutritional value of intake of E. amoenum tea has mainly been correlated to its rich content of mainly water-soluble antioxidants. Although the entire plant is utilized, only natural products of the flowers have previously been thoroughly investigated. The rare natural products bis(3-(3,4-dihydroxyphenyl)-1-methoxy-1-oxopropan-2-yl)-1-(3,4-dihydroxyphenyl)-6,7-dihydroxy-1,2-dihydronaphthalene-2,3-dicarboxylate, 4-Oxy-(E)-caffeoyl-2,3-dihydroxybutanoic acid methyl ester and 4-Oxy-(Z)-caffeoyl-2,3-dihydroxybutanoic acid methyl ester, in addition to the widely distributed compounds rosmarinic acid methyl ester and (E)-caffeic acid, were purified and characterized from leaves of Echium amoenum. The structures were determined by a combination of several 2D NMR spectroscopic techniques, circular dichroism spectroscopy and high-resolution mass spectrometry. The fact that bis(3-(3,4-dihydroxyphenyl)-1-methoxy-1-oxopropan-2-yl)-1-(3,4-dihydroxyphenyl)-6,7-dihydroxy-1,2-dihydronaphthalene-2,3-dicarboxylate belongs to a rare group of natural products which have previously been patented for their significant anti-inflammatory activity may rationalize the traditional treatment of inflammations with E. amoenum.  相似文献   

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Three new thiophene‐acetylenes, 7‐chloroarctinone‐b ( 1 ), rhapontiynethiophenes A ( 2 ) and B ( 3 ), along with arctinone‐b ( 4 ) were isolated from the MeOH extract of the roots of Rhaponticum uniflorum (L.) DC. The structures of the new compounds were elucidated by detailed spectroscopic data analysis and by comparison with known compounds.  相似文献   

18.
Aiming detection of circadian variation in the chemical composition of volatiles from Piper regnellii, the leaves were collected during four different periods (8, 12, 16 and 20 h) in the same day. After extraction by hydrodistillation and GC/MS analysis, no significant variation was observed for the main compounds: germacrene D (45.6 ± 1.5–51.4 ± 3.1%), α–chamigrene (8.9 ± 1.3–11.3 ± 2.7%) and β–caryophyllene (8.2 ± 0.9–9.5 ± 0.3%). Evaluation of in vitro cytotoxicity against several cancer and non-tumourigenic cells indicated promising activity, especially to HeLa (human cervical carcinoma) with IC50 ranging from 11 ± 3 to 17 ± 3 μg/mL. The obtained volatile oils were pooled and subjected to fractionation to afford pure β-caryophyllene, α-chamigrene and germacrene D, being this last compound the more active against HeLa cells with IC50 of 7 ± 1 μg/mL (34 ± 5 μM). Therefore, the predominance of germacrene D in all analysed oils could justify, at least in part, the activity observed for the volatile compounds from P. regnellii leaves.  相似文献   

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