Cytotoxic pyranocoumarins from the aerial parts of Peucedanum japonicum

Abstract Bioactivity-guided fractionation of a chloroform extract of the aerial parts of Peucedanum japonicum has afforded two new cytotoxic pyranocoumarins, (+)- trans -khellactone and (+)- trans -4′-acetyl-3′-tigloylkhellactone, as well as a known cytotoxic pyranocoumarin, (+)- cis -4′-acetyl-3′-angeloylkhellactone.