Journal of Antibiotics, vol. 59, no. 2, pp. 110-113
New sesquiterpenes, hirsutenols D∼F, were isolated from the fermentation broth of Stereum hirsutum, and their structures were determined on the basis of various spectroscopic analyses. Hirsutenols E and F showed significant scavenging activity against superoxide anion radicals with EC 50 values of 1.62 and 0.39 mM, respectively.