Three new meroterpenoids from culture broth of Perenniporia medulla-panis and their antioxidant activities

Three new meroterpenoids (1–3) together with one known compound (4) were isolated from the culture broth of Perenniporia medulla-panis, a wood-rotting fungus in the family Polyporaceae. Their structures were elucidated by NMR and HRESIMS analyses. These compounds exhibited antioxidant activity with IC50 values ranging from 12.8 to 190.3？μM in the 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical-scavenging assay