Cytotoxicities and anti-herpes simplex virus activities of diterpenes isolated from Euphorbia species

The cytotoxicities of nine diterpene polyesters obtained from Euphorbia species were assayed by measuring their effects on the growth of Vero cells. Their antiviral effects on the multiplication of Herpes simplex virus type 2 (HSV-2) were studied by using the virus yield reduction method in cell cultures. With the exception of the strongly cytotoxic 2 alpha ,5 alpha ,14 beta -triacetoxy-3 beta -benzoyloxy-8 alpha ,15 beta -dihydroxy-7 beta -isobutanoyloxy-9 alpha -nicotinoyloxyjatropha-6(17),11E-diene (CC50 3.5 mug/ml), all the tested diterpenes exhibited a pronounced or moderate anti-herpes virus effect (IC50 values between 2.5 and 8.3 mug/ml). The observed HSV-2 inhibitory activities were not associated with virucidal effects.