Aromatic compounds from the sclerotia of Inonotus obliquus

Three new aromatic compounds (1a/1b, 2) including a pair of enantiomers (1a/1b), were isolated from Inonotus obliquus. The structures of the new compounds were elucidated by extensive spectroscopic analyses, and the absolute configurations of 1a and 1b were determined by electronic circular dichroism (ECD) calculated. All isolates were evaluated for their cytotoxic activities against Hep3B and HepG2 cell lines. Compounds 1b and 2 showed weak cytotoxicity toward the Hep3B cells at 25 μM.