From whole plants of Coelogyne ochracea, a new pyrene, ochrolone, was
isolated. Its structure was elucidated as ydroxy-4,7-dimethoxy-9,10,10
a-trihydropyrene-3-one on the basis of spectroscopic data. This is the
first report of the occurrence of ochrolone from nature and a pyrene
from the Orchidaceae.