Brasiliensic and isobrasiliensic acids: isolation from <i>Calophyllum brasiliense</i> Cambess. and anti-<i>Helicobacter pylori</i> activity

<p>The occurrence of chromanone derivatives has been noticed as a distinctive feature of the genus <i>Calophyllum</i> (Calophyllaceae). Previous studies have demonstrated that the extract of the stem bark of <i>Calophyllum brasiliense</i> and its chromanone-rich fractions show anti-ulcer activity in murine gastric ulcer models. In this work, brasiliensic and isobrasiliensic acids, the two main compounds of the <i>n</i>-hexane extract of the stem bark extract of <i>C. brasiliense</i>, were isolated by flash chromatography using silica gel impregnated with silver nitrate and their structures were elucidated by NMR techniques and mass spectrometry. <sup>13</sup>C NMR data is available for the first time for both compounds. Brasiliensic and isobrasiliensic acids showed good <i>in vitro</i> bacteriostatic activity against <i>Helicobacter pylori</i>, and are responsible, at least in part, for the bacteriostatic anti-<i>H. pylori</i> activity of the <i>n</i>-hexane extract of the stem bark of <i>C. brasiliense</i>.</p>