Objective: To investigate the chemical constituents of the flowers of Inula helianthus-aquatica . Method: Various chromatography methods such as silica gel

RP-18 Sephadex LH-20 column chromatography

HPLC

and et al were used to isolate the compoumds from the flowers of I. helianthus-aquatica .The structures of these compounds were elucidated by spectral analysis. Result: Seven sesquiterpene lactones were isolated and elucidated as aromaticin (1)

8-epihelenalin (2)

bigelovin (3)

6- epi -desacetylisotenulin (4)

carpesiolin (5)

2

3-dihydroaromaticin (6)

ergolide (7). Conclusion: Compounds 1

2

4 and 5 were isolated from I. helianthus-aquatica for the first time.