Abstract The dichloromethane extract of the tuberous roots of Viguiera aspillioides was tested in vitro against T. cruzi and then investigated in order to identify its active compounds, which were the known diterpenes (-)-ent-kaur-16-en-19-oic acid,(-)-trachyloban-19-oic acid, and (-)-kauran-16α-ol. Synthetic derivatives of the acidic compounds were obtained and tested; one of them,(-)-kaur-16-en-19-ol, was also active. Their IC 50 are given.
