Antiproliferative activity and energy calculations of a new triterpene isolated from the palm tree <i>Acrocomia totai</i>

Abstract

<i>Acrocomia totai</i> Mart (<i>Arecaceae</i>) is a palm tree native to South America, widely studied for biodiesel production. The aim of this work was to perform the first phytochemical study of <i>A. totai</i> leaves, as well as to do biological assays against human cancer cell lines. A new triterpene of the hopane class named totaiol <b>(1),</b> three known triterpenes <b>(2-4)</b>, and two phytosteroids <b>(5-6)</b> were identified. The new natural product was characterized using 1 D and 2 D NMR, single crystal X-ray diffraction analises, and high resolution mass spectrometry. The intercontacts in the crystal packing were also analised. Complete stereochemical characterization of compound <b>1</b> revealed an unusual positioning pattern for methyl and isopropenyl groups in the polycyclic skeleton. Compounds <b>1-5</b> were evaluated for the first time in antiproliferative assays against Ca Ski, MCF-7 and MCF-10 cells. The new natural product was active against Ca Ski cells with IC₅₀ ≤ 6.25 µg mL^-1.