AbstractThe antibiotic roridin D (C29H38O9), a companion of roridin A, yields on base catalysed hydrolysis verrucarol (3) and the hitherto unknown 2, 3‐epoxy‐2‐anhydrororidinic acid (4) (C14H18O7). Roridin D is a macrocyclic diester to which structure 1 is assigned. In roridin D an epoxy group replaces the hydroxyl group of roridin A.