The Turkish endemic species Centaurea isaurica (Asteraceae) has been studied for the first time to afford 10 known compounds. Identification by mean of spectroscopic techniques revealed the presence of β-sitosterol 3-glucoside, protocatechuic acid, scopoletin, chlorogenic acid, jacein, centaurein, kaempferol-3-glucoside, quercetin 3-glucoside, arctiin and janerin. Its taxonomical classification is still uncertain being placed either in the Section Pseudoseridia or Cheirolepis. The secondary metabolites isolated in this investigation, janerin in particular, seem to suggest its placement in Section Pseudoseridia. © 2004 Elsevier Ltd. All rights reserved.