New cytotoxic sesquiterpene lactones from Anthemis scrobicularis

Four new sesquiterpene lactones, 4α-hydroxy-guaia-10(14),11(13)-diene-12,6α-olide (1), 4α-hydroxy-9α-acetoxy-guaia-1(10),2-diene-12,6α-olide (4), 4α-hydroxy-9β-acetoxy-guaia-1(10),2-diene-12,6α-olide (5), and 1α,4α-dihydroxy-9α-acetoxy-guaia-10(14),2-diene-12,6α-olide (6), were isolated from the aerial parts of Anthemis scrobicularis. Their structures were elucidated on the basis of their IR, NMR, and MS spectroscopic data. In addition, two known sesquiterpene lactones micheliolide (2) and achillin (3) were also isolated. The cytotoxicity of some of the isolated compounds was tested against HCT 116, HepG-2, and MCF-7 cell lines. Micheliolide and 4α-hydroxy-guaia-10(14),11(13)-diene-12,6α-olide showed pronounced inhibitory activity while 4α-hydroxy-9α-acetoxy-guaia-1(10),2-diene-12,6α-olide showed weak activity.