Nematicidal alkylene resorcinols from Lithraea molleoides.

Four new alkylene resorcinols, (Z,Z)-5-(trideca-4,7-dienyl)resorcinol (1), (Z,Z,Z)-5-(trideca-4,7,10-trienyl)resorcinol (2), (Z,Z,E)-5-(trideca-4,7,10-trienyl)resorcinol (3), and (Z)-5-(trideca-4-enyl)resorcinol (4), were isolated from the MeOH-CH(2)Cl(2) extract of Lithraea molleoides. The structures of these compounds were determined by one- and two-dimensional NMR including selective decoupling experiments. In vitro all four compounds showed strong paralyzing effects on the nematode Caenorhabditis elegans at concentrations between 6 and 50 microg/mL, whereas the activity of compounds 1 and 2 against the nematode Trichostrongylus colubriformis was less pronounced and no activity against this nematode was observed for compounds 1-4 in a rodent model.