Secondary metabolites from Asperula lutea subsp. rigidula.

From the aerial parts of Asperula lutea subsp. rigidula (Halacsy) Ehrend., an endemic plant of south-eastern Greece, nine known compounds, beta-sitosterol, geniposidic acid, deacetyl-asperuloside, scandoside, chlorogenic acid, quercetin, hyperin, isoquercitrin and rutin, were isolated.