Linear sesquiterpene lactones from Anthemis auriculata and their antibacterial activity.

Three linear sesquiterpene lactones, anthecotulide (1), hydroxyanthecotulide (2), and acetoxyanthecotulide (3), were isolated from the aerial parts of Anthemis auriculata. Five known flavonoids, taraxa-20(30)en-3beta-ol (4), and methyl vanillate (5) were also isolated. The structures and the relative configuration of the new compounds 2 and 3 were deduced by spectroscopic methods. The in vitro activity of compounds 1-5 against 10 bacterial species and one fungus was tested using the microdilution method.