Showing structure for 18,20-dioxa-3,13,24-triazahexacyclo[11.11.0.0²,¹⁰.0⁴,⁹.0¹⁵,²³.0¹⁷,²¹]tetracosa-1(24),2(10),4,6,8,15,17(21),22-octaen-14-one