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

The title compound, C13H13NO4, 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