2-(2,4-Di­bromo­phenyl­amino)-7-nitro­benzisoselenazol-3-one

The crystal structure determination of the title compound, C₁₃H₇Br₂N₃O₃Se, was undertaken in the course of a study on 1,2-benzoselenazin-4-one heterocycle homologues of ebselen, a well known anti-oxidizing agent. It allowed unambiguous identification of the molecular formula of the compound. The Br atom in the 4 position is split into two sites with occupation factors of 55 and 45%. The dihedral angle between the phenyl and benzisoselenazole mean planes is 85.0 (5)°. Analysis of the crystal packing shows infinite chains of mol­ecules along the b axis, linked together by an N—H⋯O intermolecular hydrogen bond.