Two new triterpenoids, lup-20(29)-en-3 alpha, 28-diol (1) and lup-20(29)-en-3 alpha, 28,30-triol (2), have been isolated from aerial parts of Bupleurum flavum, a native plant of the Eastern 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-beta-D-glucopyranoside, isorhamnetin 3-rutinoside, and rutin) were also characterized.
Six isoflavones, daidzein (4′,7,-dihydroxyisoflavone), genistein (4′,5,7-trihydroxyisoflavone), genistin (genistein 7-O-β-D-glucopyranoside), isoprunetin (4′,7-dihydroxy, 5-metoxyisoflavone), isoprunetin 7-O-β-D-glucopyranoside, isoprunetin 4′,7-di-O-β-D-glucopyranoside and four flavones, luteolin (3′,4′,5,7-tetrahydroxyflavone), luteolin 7-O-β-D-glucopyranoside, luteolin 4′-O-β-D-glucopyranoside, licoflavone C (4′,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 10−7M (0.0338μg/ml) and it was 47.45% than 10−8M 17β-estradiol (0.00272μg/ml). The estrogenicity of this flavone was found to be comparable to the activity showed by genistein at 10−6M (0.27μg/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.
From 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.
Two 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.
Alkaloids retamine, anagyrine, lupanine, 17-oxoretamine, 12-α-hydroxylupanine were detected, along with four others unidentified compounds in the aerial parts of Genista ephedroides D.C.
A 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-beta-glucoside, luteolin 7-O-beta-glucoside, taxifolin, 5-methoxytaxifolin, sucrose, and D-pinitol]. The structure of 1 was elucidated by spectroscopic methods.
Three 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.