Hispidin derivatives from the mushroom Inonotus xeranticus and their antioxidant activity.

In an effort to identify antioxidants from edible and medicinal mushrooms, three new hispidin derivatives, methylinoscavin A (2), inoscavin B (4), and methylinoscavin B (5), together with the known compounds inoscavin A and phelligridin F, were isolated from the methanolic extract of the fruiting bodies of Inonotus xeranticus. Their structures were determined on the basis of spectroscopic analyses.