Eudesmane and aromadendrane sesquiterpenoids from the Vietnamese soft coral <i>Sinularia erecta</i>

<p>Using various chromatographic separations, eight sesquiterpenoids (<b>1</b>–<b>8</b>), including one new compound 3<i>β</i>,5<i>α</i>-dihydroxyeudesma-4(15),11-diene (<b>1</b>), were isolated from the MeOH extract of the Vietnamese soft coral <i>Sinularia erecta</i>. The structure elucidation was confirmed by spectroscopic experiments including 1D and 2D NMR and HR-ESI-MS. The cytotoxic activities against three human cancer cell lines (A-549, HeLa and PANC-1) of all isolated compounds were evaluated by MTT-based colorimetric assays. Compound <b>1</b> exhibited selective cytotoxicity against the A549 cell line with IC₅₀ of 14.79 ± 0.91 μM.