Showing structure for (14r,17s,19s)-8,13,13,17-tetramethyl-21-oxa-12-azahexacyclo[10.7.1.1²,¹⁷.0⁵,²⁰.0⁶,¹¹.0¹⁴,¹⁹]henicosa-1,3,5(20),6(11),7,9-hexaene