Structure elucidation of three new acetylated flavonoid glycosides from Centaurium spicatum

Abstract

AbstractThree new acetylated flavonol glycosides, quercetin 3‐O‐(2,3,4‐triacetyl‐α‐rhamnopyranosyl)‐(1 → 6)‐β‐galactopyranoside, quercetin 3‐O‐[(2,3,4‐triacetyl‐α‐rhamnopyranosyl)‐(1 → 6)]‐3‐acetyl‐β‐galactopyranoside and quercetin 3‐O‐[(2,3,4‐triacetyl‐α‐rhamnopyranosyl)‐(1 → 6)]‐4‐acetyl‐β‐galactopyranoside, were isolated from Centaurium spicatum (L.) Fritsch (Gentianaceae). Structure elucidation, especially the localization of the acetyl groups, and complete 1H and 13C NMR assignments of these biologically active compounds were carried out using one‐ and two‐dimensional NMR methods, including 1H and 13C NMR, DEPT‐135 and DEPT‐90 and gradient‐assisted experiments such as DQF‐COSY, TOCSY, HSQC and HMBC experiments. Copyright © 2001 John Wiley & Sons, Ltd.