RESUMO
Thirteen compounds were isolated from the leaves of Rhododendron rubiginosum var. rubiginosum by various chromatographic techniques. On the basis of spectroscopic data, their structures were elucidated as 3,9-dihydroxy-megastigma-5-ene (1), 3 beta-hydroxy-5alpha ,6 alpha-epoxy-7-megastigmen-9-one (2), loliolide (3), ursolic acid(4), 2 alpha, 3 beta-dihydroxy-urs-12-en-28-oic acid (5), 2 alpha, 3 beta,23-trihydroxy-urs-12-en-28-oic acid (6), 7,9-dimethoxyrhododendrol (7), 7-methoxyrhododendrol (8), zingerone (9), isofraxidin (10), scopoletin (11), (+)-pinoresinol (12) and 3'-O-demethylepipinorisenol (13). All compounds were isolated from this plant for the first time, and compounds 1-3, 7-9, and 11-13 were isolated from the genus Rhododendron for the first time.