Experimental Crystal data

R factor = 0.047; wR factor = 0.131; data-to-parameter ratio = 17.3. The molecule of the title hydrazine derivative, C15H14N4O6, is essentially planar, the dihedral angle between the substituted benzene rings being 2.25 (9). The ethoxy and hydroxy groups are almost coplanar with their bound benzene ring [r.m.s. deviation = 0.0153 (2) A ̊ for the ten non-H atoms]. Intra-molecular N—H O and O—H Oethoxy hydrogen bonds generate S(6) and S(5) ring motifs, respectively. In the crystal, molecules are linked by O—H Onitro hydrogen bonds into chains propagating in [010]. Weak aromatic – interactions, with centroid–centroid distances of 3.8192 (19) and 4.0491 (19) Å, are also observed. Related literature For a related structure and background to hydrazones, see: Fun et al. (2013). For other related structures, see: Fun et al. (2011, 2012). For the measurement of anti-oxidant activity, see: Molyneux (2004)