Some South American Discarias (Rhamnaceae) were investigated for their secondary metabolites, and the presence of alkaloids, triterpenes, flavonoids, fatty alcohols and organic acids was established (1-5). In the course of our research on Chilean plants, we examined the aerial parts of Discaria serratijfolia, a shrub growing in the surroundings of Catillo (provincia de Concepción, VII Región, Chile). In this communication, we report the isolation and structure determination of four benzylisoquinoline bases. Two of these alkaloids are rather unusual as natural products, and this is the first time their isolation from this family has been reported. The first, R(-)-O-methylarmepavine (1), had previously been obtained by synthesis (6) and as one of the components of bisbenzylisoquinoline alkaloids cleavage products (7). Moreover, only recently, it has been isolated as a secondary metabolite from Xylopia pancheri (Annonaceae) (8). The dextrotoratory isomer has been isolated from Magnolia acuminata (Magnoliaceae) (9). The second, R(-)-demethylcollettine (2), was also isolated from Xylopia pancheri, although its quaternary derivative, colletine, was reported in 1967 from an Argentine Rhamnaceae, Colletia spinossissima (10). The other two alkaloids, R(-)-armepavine (3) and R(-)-N-methylcoclaurine (4) are common bases described in many species, including Chilean Discarias (3).