New Bioactive Semisynthetic Derivatives of 31-Norlanostenol and Obtusifoliol from Euphorbia officinarum.

Fifteen semisynthetic terpenoid derivatives from the major latex components of Euphorbia officinarum have been evaluated against the insect pest Spodoptera littoralis, two species of protozoan parasites, Trypanosoma cruzi and Leishmania infantum, and also against insect Sf9 and mammalian CHO cells to test their selective cytotoxicity. Our results showed that 40% of the test substances were postingestive toxicants to S. littoralis. All the tested derivatives had cytotoxic effects on insect-derived Sf9 cells, whereas mammalian CHO cells were affected by a lower number of compounds (47%). Furthermore, 87% of the test compounds had antiparasitic effects on both L. infantum and T. cruzi, with some of them being selective parasite toxicants.