Chemical constituents from the leaves of <i>Pinus dalatensis</i> Ferré

<p>A phytochemical study of <i>n</i>-hexane and ethyl acetate extracts of <i>Pinus dalatensis</i> Ferré leaves led to the isolation of 11 compounds, including one caryolane sesquiterpenoid (<b>1</b>), five labdane diterpenoids (<b>2</b>, <b>3</b>, <b>4</b>, <b>5, 6</b>), one serratane triterpenoid (<b>7</b>), one diacylated flavonoid glucoside (<b>8</b>), one stilbenoid (<b>9</b>) and two sterols (<b>10</b>, <b>11</b>). The structural characterisation of the isolated compounds was elucidated by spectroscopic data and comparison with the literature report on the chemical constituents from <i>Pinus dalatensis</i> Ferré. Futhermore, three compounds <b>1</b>, <b>4</b> and <b>6</b> were obtained for the first time from the genus <i>Pinus</i>. Besides, compounds (<b>2</b>, <b>3</b>, <b>5</b>, <b>8</b>, <b>9</b>) were also subjected to cytotoxicity effect on SK-LU-1, MCF-7 and Hep-G2 cell lines, but only compound <b>9</b> expressed activities with IC<sub>50</sub> values of 141.22, 127.81 and 166.84 μM, respectively.</p>