In the title compound, C11H10N2O3, which is a potential bioactive compound, the benzene and oxa-diazole rings are approximately coplanar, with an inter-ring dihedral angle of 4.14 (2)°, while the ester plane is rotated out of the benzene plane [dihedral angle = 82.69 (9)°]. In the crystal, the mol-ecules form layers down the a axis with weak π-π inter-actions between the oxa-diazole and benzene...