6,9-Dimeth­oxy-3,4-dihydro-1H-1,4-oxazino[4,3-a]indol-1-one

The title compound, C(13)H(13)NO(4), is one cyclization product of the reaction of ethyl 1-(2-bromo­eth­yl)-4,7-dimeth­oxy-1H-indole-2-carboxyl­ate with sodium azide in refluxing dioxane and was synthesized with the aim of finding new compounds with biological properties. Bond lengths and angles are within the expected values and confirm the bond orders giving in the scheme. The shortest contacts between mol­ecules are set along the a axis, where stacked mol­ecules related by an inversion center form an ABAB array through π–π stacking inter­actions with centroid–centroid distances ranging from 3.922 (2) to 4.396 (2) Å. Weak C—H⋯O hydrogen bonds further stabilize the structure.