A new biphenylpropanoid from Alpinia katsumadai

A new biphenylpropanoid, katsumadin (1), together with seven known ones cardamonin (2), (4E,6E)-1,7-diphenyl-4,6-heptadien-3- one (3), pinocembrin (4), (4Z,6E)-5-hydroxy-1,7-diphenyl-4,6-heptadien-3-one (5), 7,4'-dihydroxy-5-methoxyflavanone (6), 3,5-dihydroxystilbene (7), and alpinetin (8) were isolated from the seeds of Alpinia katsumadai Hayata and identified based on detailed spectral analysis including 2D NMR spectrometry and HRMS. Compounds 1-4 and 8 showed antiemetic activity.