Euphane and\nTirucallane Triterpenes with Trypanocidal\nActivity from <i>Euphorbia desmondii</i>

The phytochemical investigation of <i>Euphorbia\ndesmondii</i> resulted in the isolation of 15 previously undescribed\ntriterpenoids\n(desmondiins A, C-P) and 8 already described compounds. The structures\nof the isolated compounds were determined by extensive spectroscopic\nanalyses. The compounds were identified as tirucallane and euphane\ntriterpenes based on 7-keto-8-ene, 11-keto-8-ene, or 7,11-diketo-8-ene\nskeletons. Additionally, the selective trypanocidal activities of\nthese compounds against <i>Trypanosoma cruzi</i> were evaluated.\nDesmondiins A, C, D, F, H, and M exhibited IC<sub>50</sub> values\nin the range of 3–5 μM, and selectivity indices between\n5–9, against <i>T. cruzi</i> epimastigotes over the\nhost cell (RAW264.7 macrophages). Furthermore, desmondiin A efficiently\ninhibited amastigote replication in host cells (IC<sub>50</sub> =\n2.5 ± 0.3 μM), which was comparable to that of the positive\ncontrol, benznidazole (3.6 ± 0.4 μM). Overall, the isolated\neuphane and tirucallane triterpenoids could act as antichagasic lead\nscaffolds.