Crystal structure of 11-(2,3-di-meth-oxy-phen-yl)-14-methyl-12-oxa-8,14-di-aza-tetra-cyclo-[8.3.3.0(1,10).0(2,7)]hexa-deca-2(7),3,5-triene-9,13-dione.

The title compound, C22H22N2O5, contains two conformationally similar mol­ecules (A and B) in its the asymmetric unit (r.m.s. overlay fit for the 29 non-H atoms = 0.194 A). In each mol­ecule, the lactone ring has an envelope conformation with the spiro C atom as the flap. In the crystal, A+A and B+B inversion dimers linked by pairs of N—H⋯O hydrgen bonds occur; in both cases, R 2 2(8) loops are generated. A weak C—H⋯O inter­action is also observed, which links the dimers into [010] chains.