Molluscicidal activity of 2-hydroxy-3-alkyl-1,4-naphthoquinones and derivatives

Abstract

In the search for new molluscicidal agents we tested the activity of lapachol and other 2-hydroxy-3-alkylnaphthoquinones possessing nitrogenated alkyl chains, against the snail Biomphalaria glabrata. Lapachol, isolapachol and nor-lapachol showed strong molluscicidal activity against the adult snail (LD90<10 ppm) and significant toxicity against snail egg masses (LD90<0.2 ppm). As lapachol is easily extracted, and the derivatives can be synthesised without any difficulty, large-scale synthesis and field tests can be conducted, with a view to large-scale molluscicidal programs.