Showing structure for (1s,13s,21r)-16,17-dimethoxy-12-oxo-2,7,20-trioxapentacyclo[11.8.0.0³,¹¹.0⁴,⁸.0¹⁴,¹⁹]henicosa-3,5,8,10,14(19),15,17-heptaen-21-yl acetate