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1.
Two new flavones were isolated from the aerial parts of Retama raetam subsp. raetam. Their structures were established as luteolin 4'-O-neohesperidoside (1) and 5,4'-dihydroxy-(3",4"-dihydro-3", 4"-dihydroxy)-2",2"-dimethylpyrano-(5",6":7,8)-flavone (2) by means of spectroscopic methods. Also present was ephedroidin (4',5, 7-trihydroxy-8-(2-hydroxy-3-butenyl)-flavone).  相似文献   

2.
A new flavone dimer, 3-hydroxy-4',5,7-trimethoxyflavone-(6-->8")-3"-hydroxy-3"',4"', 5",7"-tetramethoxyflavone, together with amenthoflavone, have been isolated from the leaves of Ouratea multiflora. Its structure was established by spectroscopic methods, including two-dimensional NMR spectroscopy.  相似文献   

3.
Wang YF  Lai GF  Cao JX  Peng J  Qiong W 《Fitoterapia》2008,79(7-8):574-576
A new 8-O-4' neolignan glycoside was isolated from the stem bark of Tetracentron sinense. Its structure was elucidated as erythro 4',5',7, 9, 9'-pentahydroxy-3-methoxy 8-O-4'-neolignan 3'-O-beta-glucopyranoside on the basis of spectral evidence (MS, IR, 1D and 2D NMR).  相似文献   

4.
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   

5.
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   

6.
在Postband地区(27°58′4″-28°2′16″N,53°17′34″-53°22′30″E),辨别植物种、植物多样性、生活型及地中海气候、Irano-Torunian和撒哈拉-新店相关植物种。2008年6月至2006年12月间,调查和辨认了29个科,69个属,总计95个种。就物种频度而言,菊科和禾本科是重要的科。按照Raunkiaer's生活型谱系统和利用■2检测,生活型谱表明,年生植物、地面芽植物、高位芽植物、地上芽植物和陷芽植物分别占据全部植物种的47%、31%、12%、7%和3%。在地理分布上,Irano-Torunia地区,拥有最高的频度的29%的物种。结果表明,一年生植物比生活型基准群谱高;高位芽植物比生活型基准群谱低,这与在干旱地区的研究数据相一致。图1表4参50。  相似文献   

7.
Akgul YY  Anil H 《Fitoterapia》2003,74(7-8):743-745
A new benzofuran was isolated from seeds of Styrax officinalis and has been identified as 5-[3"-(2-methylbutanoyloxy) propyl]-7-methoxy-2-(3',4'-dimethoxyphenyl) benzofuran (1) by means of spectroscopic analysis.  相似文献   

8.
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   

9.
Ali DM  Wong KC  Lim PK 《Fitoterapia》2005,76(1):128-130
3,4',5-Trihydroxy-3',7-dimethoxyflavanone was isolated from the ligroin extract of the leaves of Blumea balsamifera, while the acetone extract yielded 3',4',5-trihydroxy-7-methoxyflavanone and a new biflavonoid identifed as 3-O-7'-biluteolin (1). The isolation of 1 is significant since a biflavonoid with a C-O-C linkage of the type [I-3-O-II-7] has not been previously reported from a plant.  相似文献   

10.
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   

11.
Quercetin triglycoside from Capparis spinosa.   总被引:8,自引:0,他引:8  
In addition to rutin, quercetin 3-O-glucoside and quercetin 3-O-glucoside-7-O-rhamnoside, the methanolic extract of the aerial parts of Capparis spinosa yielded the new flavonoid quercetin 3-O-[6'"-alpha-L-rhamnosyl-6"-beta-D-glucosyl]-beta-D-glucoside (1).  相似文献   

12.
A new flavanone derivative, malaysianone A (1), four prenylated flavanones, 6-prenyl-3'-methoxyeriodictyol (2), nymphaeol B (3), nymphaeol C (4) and 6-farnesyl-3',4',5,7-tetrahydroxyflavanone (5), and two coumarins, 5,7-dihydroxycoumarin (6) and scopoletin (7), were isolated from the dichloromethane extract of the inflorescences of Macaranga triloba. The structures of these compounds were elucidated based on spectroscopic methods including nuclear magnetic resonance (NMR-1D and 2D), UV, IR and mass spectrometry. The cytotoxic activity of the compounds was tested against several cell lines, with 5 inhibiting very strongly the growth of HeLa and HL-60 cells (IC(50): 1.3 μg/ml and 3.3 μg/ml, respectively). Compound 5 also showed strong antiplasmodial activity (IC(50): 0.06 μM).  相似文献   

13.
A new flavonoid (procumbenetin), isolated from the aerial parts of Tridax procumbens, has been characterised as 3,6-dimethoxy-5,7,2',3',4'-pentahydroxyflavone 7-O-beta-D-glucopyranoside (1) on the basis of spectroscopic techniques and by chemical means.  相似文献   

14.
抗月季根癌病种质资源的筛选与评价   总被引:10,自引:0,他引:10       下载免费PDF全文
2003年和2004年5月18—20日,以根癌土壤杆菌J-5-1毒性菌株在田间接种了蔷薇属50个材料,以鉴定其对根癌病的抗性。根据发病率、肿瘤大小、肿瘤干质量以及感病后植株生长状况将植物的根癌病抗性分为高度抗病、中度抗病、中度感病、高度感病4个类型。重瓣玫瑰、黄刺梅、‘红双喜’、‘火焰’、‘蓝丝带’表现为高度抗病;多花蔷薇无刺4号、无刺3号、粉团蔷薇、白玉堂等17个材料为中度抗病;荷花蔷薇、多花蔷薇无刺11号、月季花、‘梅郎口红’‘金玛丽’等17个材料为中度感病;香水月季、‘曼海姆’、‘摩纳哥公主’、‘杨基歌“桔红潮’等11个材料则表现为高度感病。为克服田间鉴定的各种限制因素,对根癌病抗性的离体接种鉴定方法作了探讨。结果表明:离体嫩梢接菌后所产生的瘤状愈伤组织量可以作为区分材料根癌病抗性的依据,离体接种与田间接种鉴定结果基本一致。  相似文献   

15.
From the resinous exudate of leaves of Haplopappus multifolius two new coumarins were isolated and assigned the structures 6-hydroxy-7-(5'-hydroxy-3',7'-dimethylocta-2',6'-dien)-oxycoumarin (1) and 6-hydroxy-7-(7'-hydroxy-3',7'-dimethylocta-2',5'-dien)-oxy coumarin (2).  相似文献   

16.
A HPLC-UV method for the quantification of six major isoflavonoids, calycosin 7-O-beta-D-glucoside (1), formononetin 7-O-beta-D-glucoside (2), (6alphaR, 11alphaR) 3-hydroxy-9,10-dimethoxypterocarpan-3-O-beta-D-glucoside (3), 7,2'-dihydroxy-3',4'-dimethoxyisoflavan-7-O-beta-D-glucoside (4), calycosin (5) and formononetin (6), in Radix Astragali (Huangqi) was developed and validated. The method was proven to be sensitive, specific, accurate and precise, as well as effective and easy.  相似文献   

17.
对2.5年生位于广东江门韦塔桉种质资源库内的母株进行控制授粉试验,结果表明:(1)不同父本花粉在相同母本上的平均座果率、平均单果产种量排序均为:尾叶桉〉韦塔桉〉巨桉,说明花粉类型对果实宿存和平均单果产种量有影响,亲缘关系越远,获得种子的可能性越小;(2)切割花柱法是缩短授粉时间、减少工作量的授粉方法;(3)参试母株W3102的座果率高,但产种量少,W3604座果率高,种子产量也高;(4)全双列育种有利于亲子代遗传关系分析,但花期不遇影响目的种子的获得,从而延长育种年限;(5)花粉对座果率的影响不如母株的影响显著。参试的8株母本座果率排序为:W3102〉W3507〉W3604〉W3401〉W3708〉W3206〉W3103〉W3105。  相似文献   

18.
Braca A  Bilia AR  Mendez J  Morelli I 《Fitoterapia》2001,72(2):182-185
Dried leaves of Licania densiflora yielded five myricetin glycosides: myricetin 3'-methylether-3-O-glucoside (1), myricetin 3'-methylether-3-O-galactoside (2), myricetin 4'-methylether-3-O-rhamnoside (3), myricetin 3',5'-dimethylether-3-O-glucoside (4), and myricetin 3',5'-dimethylether-3-O-rhamnoside (5). Their structures were elucidated by spectroscopic methods including mono- and bi-dimensional NMR techniques.  相似文献   

19.
为给调控欧李果实品质提供参考,选用'农大6号'和'农大7号'2个欧李品种果实作为试验材料,分别喷施质量浓度为50、100和150mg/L的赤霉素,测定总酚和类黄酮含量及抗氧化指标。结果表明:赤霉素处理抑制了'农大6号'欧李果实总酚和类黄酮的合成;100mg/L的赤霉素处理促进了'农大7号'欧李果实总酚和类黄酮的合成,50和150mg/L的赤霉素处理抑制了'农大7号'欧李果实总酚和类黄酮的合成。赤霉素对'农大6号'欧李果实总酚和类黄酮的抑制作用要大于'农大7号'。3个抗氧化指标(ABTS、FRAP和DPPH)中,'农大6号'欧李果实的ABTS受赤霉素作用的影响最小,'农大7号'是DPPH受赤霉素作用的影响最小。  相似文献   

20.
Li XD  Miao FP  Li K  Ji NY 《Fitoterapia》2012,83(3):518-522
Three new halogenated sesquiterpenes, 10-bromo-7α,8α-expoxychamigr-1-en-3-ol (1), 10-bromo-β-chamigren-8-ol (2), and 10-bromo-3-chlorocupar-5-en-2-ol (3), one new C12-acetogenin, desepilaurallene (7), one new naturally occurring sesquiterpene, 7-hydroxylaurene acetate (4), two known sesquiterpenes, allolaurinterol acetate (5) and laurene (6), and one known C15-acetogenin, epilaurallene (8), were isolated from the marine red alga Laurencia okamurai collected from the coast of Rongcheng, China. The structures of these compounds were unambiguously established by 1D, 2D NMR and mass spectroscopic techniques. The bioassay results showed that 4, 5 exhibited potent antibacterial activity, and 1, 4, 5 were toxic to brine shrimp.  相似文献   

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