Cytotoxicity and Structure Activity Relationship of Dammarane-Type Triterpenoids from the Bark of Aglaia elliptica against P-388 Murine Leukemia Cells

Six dammarane-type triterpenoids, dammar-24-en-$3{\beta}$-ol (1), $3{\beta}$-epicabraleahydroxy lactone (2), (E)-25-hydroperoxydammar-23-en-$3{\beta}$,20-diol (3), dammar-24-en-$3{\beta}$,20-diol (4), $3{\beta}$-acetyl-20S,24S-epoxy-25-hydroxydammarane (5), and $3{\beta}$-epiocotillol (6) were isolated from the methanolic extract of the bark of Aglaia elliptica. The chemical structure were identified on the basis of spectroscopic evidence and by comparison with those spectra previously reported. Compounds 1 - 6 were isolated first time from this plant. Compounds 1 - 6, along with a known synthetic analog, cabraleone (7) were evaluated their cytotoxic activity against P-388 murine leukimia cells in vitro. Among those compounds $3{\beta}$-acetyl-20S,24S-epoxy-25-hydroxydammarane (5) showed strongest cytotoxic activity with $IC_{50}$ value of $8.02{\pm}0.06{\mu}M$.