From the whole plant of Acampae praemorsa, a new phenanthropyran deriv
ative was isolated. Its structure was elucidated as ,7-dihydroxy-3-met
hoxy-9,10-dihydrophenanthropyran on the basis of spectroscopic data. T
his is the first report of a phenanthropyran with a 1,3,7-substitution
pattern.