1,720,963 research outputs found
FLAVONOIDS FROM CALICOTOME VILLOSA
No full textTwo new acylated flavone glycosides, chrysin 7-(6"-O-acetyl)-O-beta-D-glucopyranoside (1) and chrysin 7-(4"-O-acetyl)-O-beta-D-glucopyranoside (2) were isolated from the aerial parts of Calicotome villosa, along with 17 known flavonoids and one triterpene
A new Isoflavone from Genista corsica
No full textA new isoflavone (1), dihydroisoderrondiol [(3''S,4''R)-5,7,3'',4''- tetrahydroxy-2'',2''-dimethyl- 3'',4''dihydropyrano(5'',6'';3'',4'')isoflavone], was isolated from aerial parts of Genista corsica, together with 11 previously known compounds [daidzein, isoprunetin, isoderrone (2), ficuisoflavone (3), luteolin, luteolin 4'-O-β-glucoside, luteolin 7-O-β-glucoside, taxifolin, 5- methoxytaxifolin, sucrose, and D-pinitol]. The structure of 1 was elucidated by spectroscopic methods
Assessment of estrogenic activity of flavonoids from Mediterranean plants using an in vitro short term test
No full textSix isoflavones, daidzein (40,7,-dihydroxyisoflavone), genistein (40,5,7-trihydroxyisoflavone), genistin (genistein 7-O- b-D-glucopyranoside), isoprunetin (40,7-dihydroxy, 5-metoxyisoflavone), isoprunetin 7-O-b-D-glucopyranoside, iso- prunetin 40,7-di-O-b-D-glucopyranoside and four flavones, luteolin (30,40,5,7-tetrahydroxyflavone), luteolin 7-O-b-D- glucopyranoside, luteolin 40-O-b-D-glucopyranoside, licoflavone C (40,5,7-trihydroxy,8-isoprenylflavone) were purified from Mediterranean plants (Genista morisii and Genista ephedroides) and their estrogenic activity was assessed by a yeast reporter gene assay (Saccharomyces cerevisiae RMY326 ER-ERE). Licoflavone C showed a powerful estrogenic activity at 107 M (0.0338 mg/ml) and it was 47.45% than 108 M 17b-estradiol (0.00272 mg/ml). The estrogenicity of this flavone was found to be comparable to the activity showed by genistein at 106 M (0.27 mg/ml). This study points out that a glucose substituent in flavones and isoflavones modulates the hormone-like activity in a different way. Isoflavone aglycones showed a more estrogenic activity than the corresponding glucosides. Conversely, the glucosidation made estrogenic the flavone luteolin and the position of substitution differently influenced the estrogenic activity of compounds
FLAVONOIDS FROM GENISTA EPHEDROIDES D.C.
No full textThree new flavonoids (1-3) and 11 known compounds (genistein, isoprunetin, wighteone, laburnetin, alpinumisoflavone, genistin, genistein 8-C-glucoside, apigenin, isokaempferide, licoflavone C, and D-pinitol) were isolated from the aerial parts of Genista ephedroides. The structures of the new compounds were established as hydroxyalpinumisoflavone (1) [4',5-dihydroxy-2 "-methyl-2 "-hydroxymethylpyrano(5 ",6 ": 6,7)isoflavone], ephedroidin (2) [4',5,7-trihydroxy-8-(2-hydroxy-3-methyl-3-butenyl)flavone], and genisteone (3) (7-O-glucosylwighteone) by means of spectroscopic methods
Futher sapononins and flavonoids from Astragalus verrucosus Moris
No full textFrom the aerial parts of Astragalus verrucosus Moris, a novel cycloartane-type triterpene glycoside, named astraverrucin VII, was isolated along with cycloaraloside D (peregrinoside II) and cycloaraloside C (astrailienin A). The flavonoid composition was investigated for the first time, and fifteen known flavonoids were isolated and identified. All structural elucidation were performed by spectral means. The chemiotaxonomic importance of these findings is discussed
Lupane triterpenes from Bupleurum flavum
No full textTwo new triterpenoids, lup-20(29)-en-3α,28-diol (1) and lup-20(29)-en-3α,28,30-triol (2), have been isolated from aerial parts of Bupleurum flavum, a native plant of Easter Mediterranean area (Bulgaria, Greece and Turkey). Their structures were elucidated by spectral analysis. The known compounds betulin, betulinic acid, jasminol, together with the lignan nemerosin and eight flavonoids (kaempferol, isokaempferide, gossipetin, quercetin, luteolin, isorhamnetin-3-O-β-D-glucopyranoside, isorhamnetin-3-O-rutinoside, rutin) were also characterized
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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