New flavans and stilbenes from Cyperus conglomeratus

Publication date: August 2018Source: Phytochemistry Letters, Volume 26Author(s): Ahmed A. Zaki, Samir A. Ross, Yasser A. El-Amier, Ikhlas A. KhanAbstractThe chromatographic investigation of Cyperus conglomeratus Rottb. aerial parts resulted in the isolation of three new flavan derivatives, 7,3′-dihydroxy-8,4′-dimethoxyflavan (1), 7,4′-dihydroxy-5,3′-dimethoxy-8-methylflavan (2) and 7,4′-dihydroxy-5,3′-dimethoxy-8-prenylflavan (3), and two new stilbene derivatives, 4-hydroxy-5′-methoxy-6′′,6′′-dimethylpyran[2′′,3′′: 3′, 2′]stilbene (4) and 4′-hydroxy-3,5-dimethoxy-2-prenylstilbene (5), along with four known compounds, 5,4′-dihydroxy-7,3′-dimethoxyflavan (6), 3′,4′-dimethoxyluteolin (7), 3′,4-dihydroxy-5′-methoxy-2′-prenylstilbene (8), and 4,4′-dihydroxy-3,3′-dimethoxy-2′-prenylstilbene (9). The structures were established by their 1D, 2D NMR and MS spectral data. The new compounds 1-5 were tested for cannabinoid and opioid receptor binding. Compounds 1, 3, 4, and 5 exhibited moderate activity (>50% displacement) towards μ-opioid receptor.Graphical abstract

Source: Phytochemistry Letters - July 6, 2018 Category: Chemistry Source Type: research