A new 5-alkylresorcinol glucoside derivative from <i>Cybianthus magnus</i>

<div><p>One new 5-alkylresorcinol glucoside (<b>1</b>) was isolated from leaves of <i>Cybianthus magnus,</i> along with 12 known compounds, isolated from four plants belonging to Myrsinaceae family (<b>2, 3</b> isolated from <i>C. magnus</i>; <b>4</b>–<b>7</b>, <b>10</b> and <b>11</b> isolated from <i>Myrsine latifolia</i>; <b>4</b>, <b>8</b> and <b>9</b> isolated from <i>Myrsine sessiflora</i>; <b>6</b>, <b>7</b>, <b>10</b>, <b>12</b> and <b>13</b> isolated from <i>Myrsine congesta</i>). Their structures were determined on the basis of spectroscopic analysis and by comparison of their spectral data with those reported in the literature. So far, only nine 5-alkylresorcinol glucosides were isolated from leaves of <i>Grevillea robusta</i>. Since resorcinols are known to exhibit strong cytotoxic activity, compounds <b>1</b> and <b>2</b> were tested against cell lines 3T3, H460, DU145 and MCF-7 for cytotoxicity <i>in vitro</i> and compounds <b>3</b>–<b>13</b> were tested for their antileishmanial activity. Compound <b>2</b> displayed a strong cytotoxic activity with IC₅₀ values ranging between 22 and 100 μM for all tested cell lines. Compounds <b>3</b>–<b>13</b> were not active against <i>Leishmania amazonensis</i> amastigotes.</p></div