Rearranged Diels-Alder Adducts and Prenylated Flavonoids as Potential PTP1B Inhibitors from .

Two novel rearranged Diels-Alder adducts, morunigrines A () and B (), and four new prenylated flavonoids, morunigrols A-D (-), were isolated from the twigs of , together with four known prenylated phenolic compounds, including two flavonoids ( and ) and two 2-arylbenzofurans ( and ). Morunigrines A () and B () are a novel class of Diels-Alder adducts with unprecedented carbon skeletons featuring a rearranged chalcone-stilbene/2-arylbenzofuran core decorated with a unique methylbiphenyl moiety. The structures of the new compounds were assigned by analysis of spectroscopic data.