Investigation of a DCM extract of
the bark of Pleiogynium
timoriense from the former Merck collection of natural product
extracts for antiproliferative activity indicated that it was active
with an IC50 value of 1.3 μg/mL against the A2780
ovarian cancer cell line. Bioassay-directed fractionation of this
extract yielded the three new bioactive trihydroxyalkylcyclohexenones 1–3. Their structures were determined
by a combination of spectroscopic and chemical methods. Compounds 1–3 exhibited submicromolar antiproliferative
activity against the A2780 human ovarian cancer cell line, with IC50 values of 0.8, 0.7, and 0.8 μM, respectively.