Affiliations 

  • 1 School of Chemical Sciences, Universiti Sains Malaysia, USM, Penang, 11800, Malaysia
PMID: 21583090 DOI: 10.1107/S1600536809016225

Abstract

The title compound, C(14)H(11)BrN(4)O(4), comprises two crystallographically independent mol-ecules (A and B) in the asymmetric unit. In mol-ecule B, intra-molecular bifurcated N-H⋯O and N-H⋯Br hydrogen bonds and in mol-ecule A, an intra-molecular N-H⋯O hydrogen bond generate S(6) ring motifs. The dihedral angle between the phenyl and benzene rings is 5.44 (6) in mol-ecule A and 7.63 (6)° in mol-ecule B. The ortho- and meta-nitro substituents make dihedral angles of 6.67 (15) and 2.26 (15)° to the attached benzene ring in mol-ecule A and 6.37 (17) and 5.81 (16)° in mol-ecule B. The Br atom in mol-ecule B is disordered over two positions with a refined site-occupancy ratio of 0.61 (3):0.39 (3). Inter-esting features of the crystal structure are the short Br⋯N [3.257 (3)-3.294 (4) Å], Br⋯O [3.279 (3)-3.307 (4) Å] and O⋯O [2.9319 (16)-2.9995 (16) Å] contacts, which are shorter than the sum of the van der Waals radii of these atoms. The crystal structure is further stabilized by inter-molecular C-H⋯O and π-π inter-actions [centroid-centroid distances = 3.6643 (8)-3.8514 (8) Å].

* Title and MeSH Headings from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.