Withanolides from <i>Withania adpressa</i>

Abstract

Abstract From the leaves of Withania adpressa , a plant endemic to Sahara of Morocco and Algeria, the novel steroidal lactone (22 R )‐14 α ,15 α ,17 β ,20 β ‐tetrahydroxy‐1‐oxowitha‐2,5,24‐trien‐26,22‐olide (= (15 S ,17 S )‐14,15,17,20‐tetrahydroxy‐22,26‐epoxyergosta‐2,5,24‐triene‐1,26‐dione; 1 ), was isolated, along with three known compounds, withanolides F ( 2 ), J ( 3 ), and oleanolic acid. Their structures were mainly solved by in‐depth 1D‐ and 2D‐NMR (including ADEQUATE) experiments, as well as by HR‐MS analyses and chemical evidence.