Phytochemical constituents and chemosystematic significance of Pulicaria jaubertii E.Gamal-Eldin (Asteraceae)

The chemical characterization of methylene chloride/methanol (1:1) extract of the air-dried whole medicinal plant, Pulicaria jaubertii E. Gamal-Eldin, led to isolation and identification of two new hydroquinone compounds; 2-(2-acetoxy propyl), 5-methyl hydroquinone (1) and 2-(2-hydroxy propyl), 5-methyl hydroquinone-4-O-beta-D-glucopyranoside (2), four known flavonols (3-6) and 7 known dihydroflavonols (7-13). The structures were established depending upon comprehensive analysis of the NMR, IR and HR/EI-MS data. Herein, compounds 6, and 10 -13 were isolated for the first time from this plant. The chemotaxonomic significance of the isolated flavonoids from P. jaubertii comparing with those reported from other Pulicaria species was also summarized.