Coumarin-pi, a new antioxidant coumarin derivative from Paxillus involutus

Chemical investigation of Paxillus involutus lead to the isolation of a new coumarin derivative coumarin-pi (1), and three known compounds (2-4). The structure of the new compound was elucidated by interpretation of 1D and 2D NMR data. Compound 1 possesses a rare benzofuranylcoumarin skeleton. The isolated compounds were evaluated for antioxidant activities and coumarin-pi (1) exhibited significant activity with IC₅₀ value of 16.3 μg/mL.