Twelve 13-benzyl-15,16-bisnorlabdanes in which the C-13 and C-14 substituents are varied have been prepared from the naturally occurring labdane diterpene (+)-manool. These synthesised compounds were evaluated for antimalarial activity, in vitro as hemozoin formation inhibitors and in vivo against Plasmodium berghei. These derivatives were also assayed for antileishmanial activity against Leishmania mexicana.