Extracts from several species of the Euphorbiaceae family were evaluated as antiviral against influenza A/PR/8/34 and human rhinovirus 14(1059). The methanolic extract fm Codiaeum variegatum latex showed to be highly active and non cytotoxic to the former virus; a cyanogenic glycoside was isolated from this plant. In the other hands f the Euphorbia tirucalli latex, a triterpene was isolated; it displayed biological activity against rhinovirus. Compound structures were established through NMR spectroscopy (HMQC, HMBC y COSY) and biogenetic considerations.