Estructura y actividad leishmanicida de larnaxolida Ay B, nuevos withanolidos de Larnax glabra (Standl.) Sawyer

Two new withanolides, Larnaxolide A (1) and Larnaxolide B (2), were isolated from ethanolic extract of Larnax glabra (Standl.) Sawyer’s leaves. The structures of these compounds were established according to NMR experiments (HMQC, HMBC, and COSY) and biogenetic aspects. These compounds shown a promising leishmanicidal activity and reduced toxicity compared to another withanolides.