Sesquiterpene Lactones from Anthemis melanolepis

From the aerial parts of A. melanolepis , two new sesquiterpene lactones, melanolepin B ( = 1 α ,4 β ,8 α ‐trihydroxyeudesm‐11(13)‐en‐12,6 α ‐olide; 1 ) and melanolepin C (= 1 α ,10 β ‐epoxy‐8 β ‐hydroxygermacra‐4(15),11(13)‐dien‐12,6 α ‐olide; 2 ), were isolated, together with four known compounds, desacetyllaurenobiolide, dentatin A, taraxasterol, and (3 S ,5 R )‐loliolide. Compound 1 was found to have the rare cis ‐fused eudesmane skeleton. The structures of the isolated compounds were established by means of NMR ( 1 H, 1 H‐COSY, 1 H, 13 C‐HSQC, HMBC, NOESY) and MS analyses.