Antileishmanial diterpenoid alkaloids from <i>Aconitum spicatum</i> (Bruhl) Stapf

<p>The crude extracts of tubers of <i>Aconitum spicatum</i> (Bruhl) Stapf were investigated for <i>in vitro</i> antileishmanial activity against <i>Leishmania major</i>. The dichloromethane extract at pH 2.5 showed antileishmanial activity with IC₅₀ value of 27.10 ± 0.0 μg/mL. Chromatographic purification of the dichloromethane extract led to isolation of three C-19 norditerpenoid alkaloids indaconitine (<b>1</b>), chasmaconitine (<b>2</b>) and ludaconitine (<b>3</b>). Compounds <b>3</b> and <b>2</b> showed antileishmanial activity with IC₅₀ = 36.10 ± 3.4 and 56.30 ± 2.1 μg/mL, respectively. Compound <b>1</b> was less effective (IC₅₀ > 100 μg/mL). The cytotoxicity of compounds <b>1</b>, <b>2</b> and <b>3</b> studied against MCF7, HeLa and PC3 cancer cell lines and 3T3 normal fibroblast cell line did not show cytotoxicity at 30 μM.</p