Studies on 1-O-acetylbritannilactone and its derivative, (2-O-butyloxime-3-phenyl)-propionyl-1-O-acetylbritannilactone ester.

The crystal structures of 1-O-acetylbritannilactone 6 isolated from Inula britannica, and its derivative (2-O-butyloxime-3-phenyl) propionyl 1-O-acetylbritannilactone ester 7 are reported. The structure of synthesized derivative 7 was established by spectroscopic methods. Both compounds inhibited the growth of human HL-60, Bel-7402 cell lines and compound 7 had the stronger cytotoxic activity.