Psiguadiols A-J, Rearranged Meroterpenoids as Potent PTP1B Inhibitors from .

Psiguadiols A-J (-), new meroterpenoids with rearranged skeletons, were isolated from the leaves of . Compounds - represent the first examples of 6,8-diformyl-5,7-dihydroxy-4-phenylchromane-coupled sesquiterpenoids with an unprecedented C-8-spiro-fused 6/6/9/4 tetracyclic ring system. Compounds and represent two unusual scaffolds featuring 1β,6β- and 3α,5α-epoxy rings, respectively.