Flavonoids and aromatic compounds from the rhizomes of Zingiber zerumbet

Repeated column chromatography of the CHCl3-soluble fraction of Zingiber zerumbet led to the isolation and identification of two aromatic compounds, p-hydroxybenzaldehyde (1) and vanillin (2), and six kaempferol derivatives, kaempferol-3,4',7-O-trimethylether (3), kaempferol-3-O-methylether (4), kaempferol-3,4'-O-dimethylether (5), 4"-O-acetylafzelin (6), kaempferol-3-O-(4-O-acetyl-alpha-L-rhamnopyranoside)], 2",4"-O-diacetylafzelin (7), kaempferol-3-O-(2,4-O-diacetyl-alpha-L-rhamnopyranoside)], and 3",4"-O-diacetylafzelin (8), kaempferol-3-O-(3,4-O-diacetyl-alpha-L-rhamnopyranoside)]. The structures of 1-8 were identified by analysis of spectroscopic data as well as by comparison with published values. This is the first report on the isolation of compounds 1-3 from this plant.