Anti-inflammatory Diterpenoids from <i>Croton tonkinensis</i>

Phytochemical investigation of the methanolic extract of <i>Croton tonkinensis</i> afforded two known kauranes (<b>1</b>, <b>2</b>), eight new <i>ent</i>-kauranes (<b>3</b>–<b>10</b>), and 16 known <i>ent</i>-kaurane-type diterpenoids (<b>12</b>–<b>27</b>). In addition, 30 known compounds were identified by comparison of their physical and spectroscopic data with reported data. Among the isolated compounds, <i>ent</i>-18-acetoxykaur-16-en-15-one (<b>20</b>) displayed the most significant inhibition of superoxide anion generation and elastase release