Diethyl 7,8,18,19-tetramethyl-2,13-dioxohexacyclo[10.10.2.0<sup>3,24</sup>.0<sup>5,10</sup>.0<sup>14,23</sup>.0<sup>16,21</sup>]tetracosa-5,7,9,16,18,20-hexaene-23,24-dicarboxylate
Acta crystallographica. Section E