One-pot synthesis of (1RS,21SR)-diethyl 2-[23-amino-22-eth­oxy­carbonyl-8,11,14-trioxa-25-aza­tetra­cyclo­[19.3.1.0(2,7).0(15,20)]penta­cosa-2,4,6,15(20),16,18,22-heptaen-25-yl]but-2-endioate

The title compound, C(30)H(34)N(2)O(9) (4), is a product of the Michael reaction of aza­crown ether with dimethyl acetyl­enedi­carboxyl­ate modified by an addition of NH(3) (aq.) at 298 K. The aza-14-crown-4-ether ring adopts a bowl conformation. The dihedral angle between the planes of the benzene rings fused to the aza-14-crown-4-ether moiety is 8.65 (5)°. The tetra­hydro­pyridine ring has a boat conformation. The mol­ecular conformation is supported by one N—H⋯O and two C—H⋯O intra­molecular hydrogen bonds. Both heterocyclic and amino N atoms have essentially planar configurations (sums of the bond angles are 359.35 and 358.00°). Compound 4 crystallizes as a racemate consisting of enanti­omeric pairs of the 1R,21S diastereomer. In the crystal, mol­ecules of 4 are connected by N—H⋯O hydrogen bonds, forming chains along [100]. According to the PASS program (computer prediction of biological activities), compound 4 may exhibit anti­allergic (72% probability) and anti­asthmatic (67%) activity, as well as be a membrane permeability inhibitor (65%).