New jacaranone glucoside from <i>Jacaranda oxyphylla</i> leaves

<p><i>Jacaranda oxyphylla</i> Cham. is popularly known as ‘caroba-de-São-Paulo’ and it is used in traditional medicine for microbial infections. A new phytoquinoid (<i>α</i>/<i>β</i>-glucoside-4-phenylacetate-6-(1-hydroxy-4-oxo-2,5-cyclohexadiene-1-acetate) (<b>1</b>) was isolated from <i>J. oxyphylla</i> leaves, together with three known compounds: quercetin-3-<i>O</i>-<i>β</i>-d-galactoside (<b>2</b>), verbascoside (<b>3</b>) and polystyrene (<b>4</b>). Their chemical structures were elucidated using spectroscopic techniques and by comparison with the related known compounds. In addition, it was found a pronounced acetylcholinesterase inhibitory activity for the quinoid <b>1</b> (100.0 ± 0.8%) and phenolic compounds <b>2</b> and <b>3</b> (99.9 ± 0.7 and 99.3 ± 0.5%, respectively), if compared to the standard eserine (92.7 ± 0.4%), that was analysed by a microplate spectrophotometer.</p>