Methyl 3-[(1,1-dioxo-1λ6,2-benzothiazol-3-yl)amino]-5-nitrothiophene-2-carboxylate

• Main Authors: Haridas B. Rode, Jarosław Chojnacki, Hans-Hartwig Otto
• Format: Article
• Language: English
• Published: International Union of Crystallography 2012-10-01
• Series: Acta Crystallographica Section E
• Online Access: http://scripts.iucr.org/cgi-bin/paper?S1600536812038378

The title nitrothiophene compound, C13H9N3O6S2, crystallizes with two independent molecules in the asymmetric unit; the molecular structure of each is stabilized by an intramolecular N—H...O hydrogen bond. The two molecules adopt flattened but slightly different conformations, viz. the dihedral angle between the thiophene ring and the essentailly planar 1,2-benzisothiazole fragment (r.m.s. deviations = 0.0227 and 0.0108 Å, respectively) is 15.62 (11)° in one molecule and 5.46 (11)° in the other. In the crystal, molecules are arranged into layers parallel to (-111) with weak Car—H...O interactions formed within the layer. N—H...O hydrogen bonds also occur. There are π–π stacking interactions between the molecules in neighbouring layers, the distance between the centroids of the 1,2-benzisothiazole benzene rings being 3.8660 (16) Å. Moreover, dipolar S=O...C=O interactions with an O...C distance of 2.893 (3) Å are observed between the symmetry-independent molecules in different layers. The title compound showed weak inhibition of HLE (human leukocyte elastase).