A New Eremophilanolide Sesquiterpene From Ligularia macrophylla and Diversity of the Species

A new eremophilanolide sesquiterpene, 1 alpha,6 beta,10 beta-trihydroxyeremophila-7(11),8-dien-12,8-olide (macrophyllalarin A, 1), and along with 5 known eremophilanolide sesquiterpenes, 6 alpha,10 beta-dihydroxyeremophila-7(11)-en-12,8-olide (2), 8 beta-hydroxyeremophila-7(11)-en-12,8 alpha(15,6 alpha)-diolide (3), 6 alpha,15 beta-epoxy-8 beta-hydroxyeremophila-7(11)-en-8 alpha,12-olide (4), 6 beta,10 alpha-dihydroxy-1-oxo-eremophila-7(11),8-dien-8,12-olide (5), and 1 beta,10-epoxy-6 beta,8 beta-dihydroxyeremophila-7(11)-en-8 alpha,12-olide (6), were isolated from the roots and rhizomes of Ligularia macrophylla. The structure of the new compound was identified by comprehensive spectral analysis.