Antileishmanial and cytotoxic activities of a new limonoid and a new phenyl alkene from the stem bark of <i>Trichilia gilgiana</i> (Meliaceae)

Abstract

One new limonoid, trigilgianin (<b>1</b>), one new phenyl alkene, epoxy gilgialkene (<b>2</b>), together with five known compounds: scopoletin (<b>3</b>), sitosteryl-6'-<i>O</i>-undecanoate-<i>β</i>-D-glucoside (<b>4</b>), sitosteryl-<i>O</i>-<i>β</i>-D-glucopyranoside (<b>5</b>), cinchonain A (<b>6</b>) and cinchonain B (<b>7</b>) were isolated from the stem bark of <i>Trichilia gilgiana</i> Harms. (Meliaceae). All compounds were isolated for the first time from this species. The structures were elucidated on the basis of spectral studies and by comparison of these data with those from the literature. Compounds <b>1</b>, <b>2</b>, <b>3</b>, <b>6</b> and <b>7</b> were tested for <i>in vitro</i> antileishmanial activity against visceral leishmaniasis parasite <i>Leishmania donovani</i> and cytotoxicity against macrophage RAW 264.7 cell line. Compounds <b>1</b> and <b>3</b> showed the highest antileishmanial activity (IC₅₀ values of 6.044 and 6.804 µg/mL, respectively) with low cytotoxicity (CC₅₀ values of >200 and 47.47 µg/mL, respectively), while compound <b>2</b> was moderately active on <i>L. donovani</i> promastigotes (IC₅₀ 56.81 µg/mL).