Dimethyl 2-[24-acetyl-28-oxo-8,11,14-trioxa-24,27-diaza-penta-cyclo-[19.5. 1.122,26.02,7.015,20]octa-cosa-2,4,6,15(20),16, 18-hexaen-27-yl]but-2-enedioate

The title compound, C31H34N2O9, is a product of the Michael addition of the cyclic secondary amine subunit of the (bis-pidino)aza-14-crown-4 ether to dimethyl acetyl-ene-dicarboxyl-ate. The mol-ecule comprises a tricyclic system containing the aza-14-crown-3 ether macrocycle and two six-membered piperidinone rings. The aza-14-crown-3-ether ring adopts a bowl conformation with a dihedral angle between the planes of the fused benzene rings of 51.14 (5)°. The central piperidone ring has a boat conformation, whereas the terminal piperidone ring adopts a chair conformation. The dimethyl ethyl-enedicarboxyl-ate fragment has a cis configuration with a dihedral angle of 56.56 (7)°between the two carboxyl-ate groups. The crystal packing is stabilized by weak C-H⋯O hydrogen bonds.