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1.
Two new triterpene fatty esters, 33-tetradecanoyl moradiol 1 and 3β-dodecanoyl moradiol 2, were isolated from Scorzonera mongolica. Their structures were elucidated as 3β-tetradecanoyloxy-28-hydroxylolean-18-ene and 3β-dodecanoyl-28-hydroxyl-olean-18-ene on the basis of IR, MS, ID NMR and extensive 2D NMR spectroscopic analyses.  相似文献   

2.
A New Sesquiterpene Lactone from Scorzonera austriaca   总被引:2,自引:0,他引:2  
A new guaianolide was isolated from the roots of Scorzonera austriaca. The structurewas elucidated on the basis of spectral methods including 2D NMR.  相似文献   

3.
Chromatographic separation ofn-hexane and ethyl acetate fraction of a crude methanol extract obtained from aerial parts of theScorzonera aucherianaDC collected from Sivas province of Turkey yielded nine natural compounds; two new 3-caffeoyl-quinic acid analogs (1-2), one new taraxasterol oleate (3), and six known triterpenoids taraxasterol (4), taraxasterol acetate (5), ptiloepoxide (6), lupeol (7), lupeol acetate (8), andβ-sitosterol (9) were characterized. The structures of the isolated compounds were elucidated on the basis of NMR (1H,13C, COSY, HMBC, HSQC, and TOCSY), UV, FT-IR and LC-Q-TOF-MS spectrometric data.  相似文献   

4.
总酚具有抗氧化、捕捉自由基、抑菌等作用,在食品加工、果蔬加工、贮藏、医药等方面都有应用价值。对岗稔果实中有效成分总酚进行提取,并测定其含量。为岗稔在实际产业中应用提供参考。  相似文献   

5.
A novel diterpene, named effusenone A ( 1a ), which is the first reported rosane‐type diterpene from a Juncaceae plant, and three novel phenolic compounds, 5‐(hydroxymethyl)‐1‐methylphenanthrene‐2,7‐diol ( 4 ), 1‐methylpyrene‐2,7‐diol ( 5 ), and 7‐methoxy‐8‐methylpyren‐2‐ol ( 6 ) were isolated from the stem of Juncus effusus L. by normal‐phase and reversed‐phase silica gel column chromatography. Their structures were identified by spectroscopic methods, especially 2D‐NMR techniques.  相似文献   

6.
Fourteen polyphenolic compounds were isolated from the 60% aqueous acetone extract of Formosan Euphorbia tirucalli L. (Euphorbiaceae). Two compounds, 5‐desgalloylstarchyurin and 3,3′,4‐tri‐O‐methyl‐4′‐O‐rutinosyl ellagic acid, were deduced by concerted application of 1D and 2D NMR methods, and reassigned their NMR data.  相似文献   

7.
Seven phenolic compounds, including one new compound trans‐3,4,3′,5′‐tetrahydroxy‐4′‐methylstilbene 4‐O‐β‐D‐xylopyranosyl‐(1→6)‐β‐D‐glucopyranoside ( 1 ), together with six known compounds (+)‐hinokiol ( 2 ), 6‐hydroxy‐5,7‐dimethoxycoumarin ( 3 ), caffeic acid ( 4 ), vanillic acid ( 5 ), 4‐hydroxy‐2,6‐dimethoxyphenol‐1‐O‐β‐D‐glucopyranoside ( 6 ) and 4‐allyl‐2,6‐dimethoxyphenol‐1‐O‐β‐D‐glucopyranoside ( 7 ), were isolated from the root bark of Elsholtzia bodinieri Van't. Their structures were determined on the basis of spectroscopic and chemical evidence.  相似文献   

8.
The oxidative cyclization reactions of 1,3‐dicarbonyl compounds 1a – 1c and α,β‐unsaturated alcohols 2a – 2f with Mn(OAc)3 were performed, leading to dihydrofurans. Treatment of 1a and 1b with 2‐methylbut‐3‐en‐2‐ol ( 2a ) gave dihydrofurans 3aa and 3ba , and dihydropyrans 4aa and 4ba , as unexpected products. While the reaction of 2‐methylbut‐3‐yn‐2‐ol ( 2b ) with acetylacetone ( 1b ) yielded a bifuran, ethyl acetoacetate ( 1a ) led to a mixture of furan, bifuran, and salicylate derivatives. Besides, surprisingly, styryl‐substituted dihydrofurans were obtained from the reactions of 1,3‐dicarbonyl compounds and (3E)‐2,4‐diphenylbut‐3‐en‐2‐ol. The reaction mechanisms were proposed for the formation of the different products, considering intermediates in these reaction mixtures.  相似文献   

9.
Bridelia tomentosa Bl., a small shrub in the Euphorbiaceae family, is widely distributed in Taiwan, Guangdong, Guangxi and Yunnan Provinces of south China. As a traditional medicine, it is used for curing neurasthenic, turbulence of emmenia, bite of dog, …  相似文献   

10.
A New Triterpenoid Saponin from Anemone tomentosa   总被引:2,自引:0,他引:2  
TherootsofAnemonetomentosa(Maxim.)PeiareusedasafolkmedicineforthetreatmentofdysenteriainChinal.Recently,twonewcoumarinsandnineknowncompoundswereisolatedfromtheethylacetateeXtractwhichexhibitedstrongantifeedantactivityagainstLeucaniaSeparataWailiee.Duringthefurtherinvestigationofthetitleplant,anewminorsaponin,tomentoside,togetherwithfourknownoneswasisolated.Tomentoside(5),amorphouspowder,[a]D-41.5(MeOH,c0.26).MolecularformulawasdeterminedasC,,H,,.O,.byHRFABMS,m/zf1497.7166([M-H]-),caf…  相似文献   

11.
Two new phenolic compounds, (Z)‐5′‐hydroxyjasmone 5′‐O‐{6″‐O‐[(E)‐caffeoyl]‐β‐D ‐glucopyranoside} ( 1 ) and quercetin‐7‐Oβ‐D ‐glucuronide methyl ester ( 2 ), along with ten known phenolic compounds, 3 – 12 , were isolated from the aerial parts of Artemisia iwayomogi. Their structures were elucidated by spectroscopic methods, including 1D‐ and 2D‐NMR, and HR‐ESI‐TOF‐MS techniques. The inhibitory effects of compounds 1 – 12 on the LPS‐stimulated production of IL‐12 p40, IL‐6, and TNF‐α in bone marrow‐derived dendritic cells were evaluated.  相似文献   

12.
A new 3-benzylphthalide, scorzoveratrin 4'-O-β-glucoside (1), together with the known 3-benzylphthalides, scorzoveratrin (2) and scorzoveratrozit (3), the caffeoyl derivatives, chlorogenic acid methyl ester (4), 4,5-dicaffeoylquinic acid (5), 4,5-dicaffeoylquinic acid methyl ester (6), 3,5-dicaffeoylquinic acid (7) and caffeic acid (8) were isolated from the subaerial parts of Scorzonera latifolia (Fisch. & Mey.) DC. All secondary metabolites were assigned using physicochemical and spectroscopic data. The known compounds 2-8 were isolated for the first time from this species.  相似文献   

13.
Abstract

Phytochemical composition of ethyl acetate fraction and total phenolic content, in vitro antioxidant, anti-inflammatory, antimicrobial activities of petroleum ether, chloroform, ethyl acetate and n-butanol fractions of the ethanol extract obtained from the subaerial parts of Scorzonera pygmaea Sibth. & Sm. (Asteraceae) were investigated. Nine compounds; scorzopygmaecoside (1), scorzonerol (2), cudrabibenzyl A (3), thunberginol C (4), scorzocreticoside I (5) and II (6), chlorogenic acid (7), chlorogenic acid methyl ester (8), 3,5-di-O-caffeoylquinic acid (9) were isolated and identified using spectroscopic methods. All substances were isolated for the first time from this species. Compounds 1 and 2 are new. The fractions showed high antioxidant capacity correlated with their phenolic content and no significant antimicrobial activity against tested bacteria and fungi. COX inhibition test was used to evaluate the anti-inflammatory activity and all the fractions showed low inhibition in comparison with indomethacin.  相似文献   

14.
The [Cu(acac)2]‐catalyzed reactions of several tertiary enaminones with three diazocarbonyl compounds, i.e., dimethyl diazomalonate, ethyl diazoacetoacetate, and ethyl diazoacetate, yielded amino‐ and additionally carbonyl‐substituted dihydrofurans, together with further furan derivatives. Due to the conjugation of α‐carbonyl/α‐Ph groups, reactions proceeded only via 1,5‐electrocyclization of corresponding keto‐ylides. On the other hand, in the absence of any α‐substituent, tertiary enaminone and ethyl diazoacetate, reacted via an accompanying mechanism by a push‐pull cyclopropane intermediate, to yield a 2,4‐dicarbonyl‐substituted furan in one step with moderate yield.  相似文献   

15.
Various polycyclic arenes, such as naphthalenes, tetrahydroantharacenes, tetrahydrotetracenes, dihydropentacenes, and dihydropentaphenes are prepared from 2‐alkenylphenyl ketones and aldehydes by the catalytic use of copper(II) trifluoromethanesulfonate (Cu(OTf)2) or trifluoromethanesulfuric acid (TfOH).  相似文献   

16.
A clean and efficient tandem oxidative cyclocondensation process is reported for the synthesis of 3,4‐dihydropyrimidin‐2(1H)‐one or ‐thione derivatives from primary aryl alcohols, β‐keto esters, and urea or thiourea in the presence of Al(NO3)3?9 H2O as oxidant catalyst (Scheme, Table 5).  相似文献   

17.
Eight spiro‐biflavonoids named abiesinols A–H, along with three neolignans, quercetin, and protocatechuic acid were isolated from the MeOH extract of the bark of Abies sachalinensis. The structures of these phenolic compounds were characterized by spectroscopic methods including NMR and MS. The absolute configurations of the abiesinols were determined by Mosher's method, CD, and NOESY data.  相似文献   

18.
Two new natural products, i.e., 1‐O,2‐O‐[(1S,2S)‐1‐(3‐acetyl‐2,4,6‐trihydroxyphenyl)‐3‐hydroxypropane‐1,3‐diyl]‐β‐D ‐glucopyranose (=tomentoside I; 1 ) and (3β)‐3‐(acetyloxy)ferruginol 12‐[6‐O‐(4‐hydroxy‐3,5‐dimethoxybenzoyl)‐β‐D ‐glucopyranoside] (=tomentoside II; 2 ), were isolated from the EtOH extract of the root of Anemone tomentosa, together with five known compounds. Their structures were characterized by means of spectroscopic methods, especially by 1H‐, 13C‐, and 2D‐NMR and HR‐MS, as well as by chemical methods and comparison with literature data.  相似文献   

19.
Information on flavones, flavanones, flavanonols, flavonols, chalcones, isoflavones, biflavonoids, lignoflavonoids, and lignane glycosides and stilbenes isolated from plants of the Scutellaria L. genus was systematized and reviewed. A list of 208 phenolic compounds was given according to flavonoid type with an indication of the plant sources, structures, and physicochemical properties and citations of the original articles.  相似文献   

20.
A novel and efficient isocyanide‐based multicomponent reaction between alkyl or aryl isocyanides 1 , 2,3‐diaminomaleonitrile ( 2 ), naphthalene‐2,3‐diamines ( 6 ) or benzene‐1,2‐diamine ( 9 ), and 3‐oxopentanedioic acid ( 3 ) or Meldrum's acid ( 4 ) or ketones 7 was developed for the ecologic synthesis, at room temperature under mild conditions, of 1,6‐dihydropyrazine‐2,3‐dicarbonitriles 5a – 5f in H2O without using any catalyst, and of 3,4‐dihydrobenzo[g]quinoxalin‐2‐amine and 3,4‐dihydro‐3,3‐dimethyl‐quinoxalin‐2‐amine derivatives 8a – 8g and 10a – 10e , respectively, in the presence of a catalytic amount of p‐toluenesulfonic acid (TsOH) in EtOH, in good to excellent yields (Scheme 1).  相似文献   

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