Identification of Secondary Metabolites from the Stems of Viburnum erosum

The stems of Viburnum erosum were extracted with 80% MeOH. The concentrated extract was partitioned with EtOAc, n-BuOH, and . From the EtOAc and n-BuOH fractions, four compounds were isolated through the repeated , octadecyl silica gel, and Sephadex LH-20 column chromatographies. Based on NMR, MS, and IR spectroscopic data, the chemical structures were determined as betulinic aldehyde (1), koaburside (2), (6R,7E,9R)-9-hydroxymegastigma-4,7-dien-3-one-9-O--D-glucopyranoside (3), and byzantionoside B (4). All the compounds were isolated for the first time from the stems of Viburnum erosum.