Cytotoxic and Antioxidant Compoundsfrom the Stem Bark of Goniothalamus tapisoides Mat Salleh

Eleven compounds:goniomicin A ( 1), goniomicin B ( 2), goniomicin C ( 3), goniomicin D ( 4), tapisoidin ( 5), goniothalamin ( 6), 9-deoxygoniopypyrone ( 7), pterodondiol ( 8), liriodenine ( 9), benzamide ( 10) and cinnamic acid ( 11), were isolated from the stem bark of Goniothalamus tapisoides. All compounds were identified by spectroscopic analysis and, for known compounds, by comparison with published data. Goniothalamin ( 6) exhibited mild cytotoxic activity towards a colon cancer cell line (HT-29), with an IC 50value of 64.17 ± 5.60 μM. Goniomicin B ( 2) give the highest antioxidant activity in the DPPH assay among all compounds tested, with an IC 50 of 0.207 μM.