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Chemical constituents of Centaurea omphalotricha Coss. & Durieu ex Batt. & Trab.

Soumia Mouffok, Hamada Haba, Catherine Lavaud, Christophe Long and Mohammed Benkhaled

Laboratoire de Chimie et Chimie de l’Environnement (L.C.C.E), Département de Chimie, Faculté des Sciences, Université de Batna, Batna 05000, Algeria

Laboratoire de pharmacognosie, Institut de Chimie Moléculaire de Reims, CNRS UMR 6229, BP 1039, 51097 Reims Cedex 2, France

Centre de Recherche sur les Substances Naturelles, UMS CNRS 2597, 3 rue des Satellites, BP 94244, 31432 Toulouse, France

Abstract: The investigation of the aerial parts of Centaurea omphalotricha Coss. & Durieu ex Batt. & Trab. allowed the isolation of nine secondary metabolites corresponding to five flavonoids: oroxylin A (1), chrysin (2), tenaxin II (3), 5,7,2’-trihydroxyflavone (4) and quercetin (5), and four triterpenoids: lupeol (6), taraxasterol (7), daucosterol (8) and β-sitosterol (9). Their structures were established by spectroscopic methods such as 1H and 13C NMR, COSY, HSQC, and HMBC experiments, and ESI-MS, and comparison with literature data. The flavonoids tenaxin II (3) and 5,7,2’-trihydroxyflavone (4) are new for the genus Centaurea L.

Keywords: Centaurea omphalotricha ; Asteraceae; flavonoids; triterpenoids.