The antiviral activity of extracts obtained from Ageratina havanensis (Kunth) R.M.King & H.Rob., Asteraceae, against rabbit vesivirus (RaV) (Caliciviridae) and human herpes simplex viruses type 1 and 2 (HSV-1, HSV-2) (Herpesviridae) were analyzed, and the main metabolites from the most active extract were isolated and characterized. The antiviral properties were investigated by measuring the inhibition of viral-induced cytopathic effect in Vero cells. The strongest inhibitory effects were found for ethyl acetate extract from leaves (SI=5 for RaV and SI=5.4 for HSV-1). The crude ethyl acetate extract was further fractionated by chromatographic methods and the structures of isolated compounds were established through comprehensive spectroscopic analyses, including IR, 2D NMR and MS. Four flavonoids were identified: 5,4'-dihydroxy-7-methoxyflavanone (sakuranetin), 3,5,4'-trihydroxy-7-methoxyflavanone (7-methoxyaromadendrin), 4'-O-β-D-glucosyl-5,3'-dihydroxy-7-methoxyflavanone (4'-O-β-D-glucosyl-7-methoxy-eriodictyol) and 4'-O-β-D-glucosyl-5-hydroxy-7-methoxyflavanone (4'-O-β-D-glucosylsakuranetin). This is the first report on antiviral activity for Ageratina havanensis.

Interest in natural products as a source for innovation in drug discovery and agrochemicals is still growing worldwide. Natural products, whose immense diversity has been appreciated for many years, may become in a rich source of novel chemical structures. Our country is a rich source of both biological and chemical diversity which may be useful as a source of novel chemical structures. Even when natural products have been used as medicinal agents for many years in Cuba, their use as agrochemicals are still limited. Thus, the present review focuses on recent advances in the studies on natural products performed by the "Centro de Estudios de Productos Naturales, CEPN" during the past ten years, highlighting on those with potential use as biomedical and agrochemicals. 15 plant species were studied; Agave brittoniana Trel. Subsp. brachypus A Álvarez de Zayas (Agavaceae); Juniperus barbadensis L. var. Lucayana (Britt.) RP Adams (Cupressaceae); Melia azedarach Linn. (Meliaceae); Tectona grandis Linn. f. (Lamiaceae); Lantana camara Linn. (Verbenaceae); Lantana trifolia Cham. (Verbenaceae); Citrus sinensis (Linn.) Osbeck cv Valencia (Rutaceae); Maytenus buxifolia (A Rich) Griseb (Celastraceae); Maytenus elaeodendroides Griseb (Celastraceae); Maytenus urquiolae B Mory (Celastraceae); Solanum americanum W. Mill (Solanaceae); Thalassia testudinum Kon. (Hydrocharitaceae); Sesbania rostrata Bremek & Oberm (Fabaceae); Pluchea carolinensis G Don (Asteraceae) and Ageratina havanensis (HB & K) RM King & Robinson (Asteraceae). By means of a bio-guided fractionation, isolated structures as well as semi-purified fractions were assayed as antioxidant, antiparasitic, antibiotic, insecticides, antifungal, and skin regenerating and healing effects. The strategy employed allows us to discover novel secondary metabolites with potential for industrial development as pharmaceuticals and/or agrochemicals. Besides, in addition to the goal of discovering new bioactive agents, the presence of unique bioactive compounds notably contribute to increase the knowledge of plant species in Cuba.