Three-dimensional hydrogen-bonded assembly in 2,2′-disulfanylidene-5,5′-biimidazolidinylidene-4,4′-dione–dimethylformamide–water (3/2/4)

Abstract

The title compound, 3C6H4N4O2S2·2C3H7NO·4H2O, comprises three 2,2′-disulfanylidene-5,5′-biimidazolidinylidene-4,4′-dione molecules, two dimethylformamide molecules and four water molecules arranged around a crystallographic inversion centre. The non-H atoms within the 5,5′-biimidazolidinylidene molecule are coplanar and these molecules aggregate through N—H...S hydrogen-bonding interactions with cyclic motifs [graph setR22(8)], giving two-dimensional ribbon structures which are close to being parallel. The two independent water molecules associate to form centrosymmetric cyclic hydrogen-bonded (H2O)4tetrameric units [graph setR44(8)]. The ribbon structures extend along theaaxis and are linked through the water tetramers and the dimethylformamide molecules by a combination of two- and three-centre hydrogen bonds, giving an overall three-dimensional structure.