Abstract

The asymmetric unit of the title compound, C10H6N4O4S2, contains two independent but similar mol-ecules. The structure is a triclinic polymorph of the monoclinic structure reported previously [Brito, Mundaca, Cárdenas, López-Rodríguez & Vargas (2007). Acta Cryst. E63, o3351-o3352]. The most obvious difference between the two polymorphs is the C - S - S - C torsion angle [-80.13 (16), -79.8 (2) and 0° for the two mol-ecules of the triclinic polymorph and the monoclinic polymorph, respectively]. The crystal structure of the title compound has two intra-molecular C - H⋯S inter-actions with average H⋯S distances of 2.69 Å, whereas this kind of inter-action is not evident in the monoclinic polymorph. © International Union of Crystallography 2008.