Sterehirsutynes A − C: three new acetylenic aromatic metabolites from Stereum hirsutum

Abstract

Three new acetylenic aromatic compounds, sterehirsutynes A–C (1–3), along with three known congeners, frustulosinol (4), vibrayne (5), and sterehirsutinol (6), were isolated from the culture broth of Stereum hirsutum. Their structures were determined by detailed analyses of NMR and high-resolution mass. Chiral column analysis showed that compounds 2 and 3 were racemic mixtures. These new compounds were evaluated for porcine pancreatic lipase (PPL) inhibitory activities, and compounds 1 and (±) 3 showed moderate inhibitory activity against PPL, with IC50 values of 23.2 ± 1.04 and 21.8 ± 2.15 μM, respectively.