(1S*,4′S*,5R*)-1-Isopropyl-5-meth­oxy-2′,3-dimethyl-4,6-dioxa-2-aza­spiro­[bicyclo­[3.2.0]hept-2-ene-7,4′-isoquinoline]-1′,3′(2′H,4′H)-dione

In the isoquinoline ring system of the title mol­ecule, C(18)H(20)N(2)O(5), the N-heterocyclic ring is in a half-boat conformation. The dioxa-2-aza­spiro ring is essentially planar, with a maximum deviation of 0.029 (1) Å, and makes a dihedral angle of 30.63 (5)° with the benzene ring. The mol­ecular structure is stabilized by a weak intra­molecular C—H⋯O hydrogen bond, which generates a S(6) ring motif. In the crystal, mol­ecules are linked via weak inter­molecular C—H⋯O hydrogen bonds into a three-dimensional supra­molecular network. Additional stabilization is provided by π–π stacking inter­actions between symmetry-related benzene rings with a centroid–centroid distance of 3.6507 (5) Å.