On the influence of the sugar moiety on the antigonadotropic activity of luteoline glycosides

: Luteolin-7-glucoside and luteolin-7-glucuronide were isolated from Lycopus europaeus L. (Lamiaceae) and identified by 1H- and 13C-NMR spectroscopy. Luteolin-7-glucuronide proved to be active against PMSG in vitro as well as in vivo, whereas the other flavone glycosides occurring in the plant were completely inactive.