New eudesmane-type sesquiterpenoids from the root bark of Pseudolarix kaempferi

The phytochemical investigation of the root bark of Pseudolarix kaempferi yielded eight eudesmane-type sesquiterpenoids, including three new ones, 1α-hydroxyl-4(14)-en-β-dihydroagarafuran (1), 1α, 2α-diacetoxy-8β-isobutanoyloxy-9α-benzoyl oxy-15-β-(β-furancarbonyloxy)-4β, 6β-dihydroxy-β-dihydroagarofuran (7), and 1α-acetoxy-2 α-furancarbonyloxy-8β-isobutanoyloxy-9α-benzoyloxy-15β-(β-acetoxy)-4β, 6β-dihydroxy-β-dihydroagarofuran (8). Herein the new compounds 7 and 8 were reported as a mixture. The molecular structures of the isolated compounds were elucidated on the basis of extensive spectroscopic analysis, including UV, IR, NMR, and MS, and comparison with the literature data.