Isolation of new sesquiterpene lactones from Inula britannica with centrifugal partition chromatography

Inula britannica produces a variety of biologically active sesquiterpene lactones mainly pseudoguaianolides and seco-eudesmanolides. In order to further study the chemical constituents of I. britannica we used centrifugal partition chromatography followed by semi-preparative HPLC to isolate 10 sesquiterpene lactones. Three new seco-eudesmanolides ( 1–3 ) were isolated in the course of these experiments. The structure elucidation of these compounds was accomplished with high resolution MS, 1 H-NMR, 13 C-NMR, COSY, HSQC, HMBC, and NOESY.