4,4-dimethyl-5-[(Z)-4-methyl-4-(2-methyl-[1,3]dioxolan-2-yl)-2-oxo-pentylidene]-pyrrolidin-2-one

3-methyl-3-{5-[2-methyl-2-(2-methyl-[1,3]dioxolan-2-yl)-propyl]-isoxazol-3-yl}-butyric acid methyl ester