Sesquiterpene lactones. XXIII. Isolation of sesquiterpene lactones from Centaurea L. species

Sesquiterpene lactones were isolated from 18 species or subspecies of the genus Centaurea L.: salonitenolide (I) was found in C. crithmifolia Vis., C. friderici Vis., C, paniculata L., C. calcitrapa L., C. pontica Prodan et E. L' Nyarady, C. eriophora L., C. alba L. subsp. deusta (Ten.) Nyman, C. alba L. subsp. caliacrae (Prodan) Dostal and C. weldeniana Reichenb.; cnicin (II) was found in: C. vallesiaca (DC). Jordan, C. calcitrapa L., C. aspera L. subsp. aspera, C. sphaerocephala L. subsp. lusitanica (Boiss. et Reuter) Nyman, C. sulphurea Willd., C. eriophora L. and C. rocheliana (Heuffel) Dostal; cynaropicrin (III) was detected in C. debeauxii Gren. et Gordon subsp. thuillieri Dostal; acroptillin (V), repin (VI) and janerin (VII) in C. bella Trautv. Other unidentified sesquiterpene lactones were also found to be present in the examined plants