A bioactive cycloartane triterpene from <i>Garcinia hombroniana</i>

<p>The dichloromethane bark extract of <i>Garcinia hombroniana</i> yielded one new cycloartane triterpene; (22<i>Z</i>,24<i>E</i>)-3<i>β</i>-hydroxycycloart-14,22,24-trien-26-oic acid (<b>1</b>) together with five known compounds: garcihombronane G (<b>2</b>), garcihombronane J (<b>3</b>), 3<i>β</i> acetoxy-9<i>α</i>-hydroxy-17,14-friedolanostan-14,24-dien-26-oic acid (<b>4</b>), (22<i>Z</i>, 24<i>E</i>)-3<i>β</i>, 9<i>α</i>-dihydroxy-17,14-friedolanostan-14,22,24-trien-26-oic acid (<b>5</b>) and 3<i>β</i>, 23<i>α</i>-dihydroxy-17,14-friedolanostan-8,14,24-trien-26-oic acid (<b>6</b>). Their structures were established by the spectral techniques of NMR and ESI-MS. These compounds together with some previously isolated compounds; garcihombronane B (<b>7</b>), garcihombronane D (<b>8</b>) 2,3’,4,5’-tetrahydroxy-6-methoxybenzophenone (<b>9</b>), volkensiflavone (<b>10</b>), 4’’-<i>O</i>-methyll-volkensiflavone (<b>11</b>), volkensiflavone-7-<i>O</i>-glucopyranoside (<b>12</b>), volkensiflavone-7-<i>O</i>-rhamnopyranoside (<b>13</b>), Morelloflavone (<b>14</b>), 3’’-<i>O</i>-methyl-morelloflavone (<b>15</b>) and morelloflavone-7-<i>O</i>-glucopyranoside (<b>16</b>) were evaluated for cholinesterase enzymes inhibitory activities using acetylcholinesterase and butyrylcholinesterase. In these activities, compounds <b>1–9</b> showed good dual inhibition on both the enzymes while compounds <b>10–16</b> did not reasonably contribute to both the cholinesterases inhibitory effects.</p