Rubescins I and J, further limonoid derivatives from the stem bark of <i>Trichilia rubescens</i> (Meliaceae)

<p>Two new tetranorterpenoid derivatives named rubescins I (<b>1</b>) and J (<b>2</b>), were isolated along with six known compounds including rubescin D (<b>3</b>), lichexanthone (<b>4</b>), scopoletin (<b>5</b>), scopoletin <i>O</i>-glycoside (<b>6</b>), <i>β</i>-sitosterol (<b>7</b>) and stigmasterol (<b>8</b>) from the stem bark of <i>Trichilia rubescens</i> (Meliaceae). The structures of the compounds were determined by means of MS, different NMR and by comparison with related data reported in the literature.</p