Bioactive neolignans from Endlicheria dysodantha

From bioactivity-directed fractionation of the EtOH extract of Endlicheria dysodantha, dysodanthin A and dysodanthin B, which are new hexahydrobenzofuranoid neolignans, have been isolated. In addition, the known neolignans, compound 4, which is a burchellin analogue, and megaphone acetate [1] were isolated. All four neolignans showed activities in the brine shrimp lethality test; compounds 1-3 also inhibited the growth of crown gall tumors on potato discs and were cytotoxic to human tumor cells in culture. This is the first report of these neolignans isolated from the genus Endlicheria and of their completely assigned 1H-and 13C-nmr data.