Chemical and Genetic Identity of Ligularia tsangchanensis and L. muliensis. Isolation of a Cacalol Precursor from a Hybrid of L. tsangchanensis and L. vellerea

The chemical composition and the DNA sequence of an evolutionarily neutral region were studied for three samples of L. tsangchanensis, three samples of L. muliensis, and one sample of a hybrid between L. tsangchanensis and L. vellerea. L. tsangchanensis and L. muliensis were indistinguishable in the chemical composition and the ITS sequence, supporting a recent taxonomic study that merged the two species into L. tsangchanensis. Cacalol (1) was isolated as the most major component from both L. tsangchanensis and L. muliensis, while 6-acetoxy-9-oxofuranoeremophilane (10), a putative cacalol precursor, was isolated from the hybrid.