New naphthoquinones and an alkaloid with in vitro activity against Toxoplasma gondii RH and EGS strains

► Amino-terpenyl naphthoquinones inhibited replication of Toxoplasma gondii tachyzoites. ► Alkaloid liriodenine also showed activity against T. gondii tachyzoites. ► All compounds demonstrated lower toxicity for fibroblasts. ► They inhibit the infectivity of bradyzoites after in vitro incubation.