| Summary: | The dichloromethane extract from leaves of <i>Melicope barbigera</i> (Rutaceae), endemic to the Hawaiian island of Kaua’i, yielded four new and three previously known acetophenones and 2<i>H</i>-chromenes, all found for the first time in <i>M. barbigera</i>. The structures of the new compounds obtained from the dichloromethane extract after purification by chromatographic methods were unambiguously elucidated by spectroscopic analyses including 1D/2D NMR spectroscopy and HRESIMS. The absolute configuration was determined by modified Mosher’s method. Compounds <b>2</b>, <b>4</b> and the mixture of <b>6</b> and <b>7</b> exhibited moderate cytotoxic activities against the human ovarian cancer cell line A2780 with IC<sub>50</sub> values of 30.0 and 75.7 µM for <b>2</b> and <b>4</b>, respectively, in a nuclear shrinkage cytotoxicity assay.
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