Antiemetic principles of Alpinia officinarum.

Bioasay-guided fractionation of the antiemetic constituents of Alpinia officinarum was performed, and eight compounds (1-8) including a new compound were isolated. Among the seven known compounds, two flavonoids (1, 2), four diarylheptanoids (3, 5, 6, 8), and one sterol (4) were obtained, with five (2-6) of those compounds showing antiemetic activity in a copper sulfate induced emesis assay in young chicks. The structure of the new compound 7, which also showed antiemetic activity, was determined as 5-hydroxy-7-(4-hydroxy-3-methoxyphenyl)-1-(4-hydroxyphenyl)-3-heptanone. The structure of 7 was established on the basis of spectroscopic data interpretation.