N-[(E)-(2,4-Dinitro­phen­yl)methyl­ene]aniline

The title compound, C₁₃H₉N₃O₄, was obtained from the condensation reaction of 2,4-dinitro­benzaldehyde and aniline. It crystallizes with two independent mol­ecules in the asymmetric unit. In the aniline moiety, the C=N and C—N bond lengths are normal. The crystal packing reveals short contacts [3.374 (2)–3.632 (3) Å] between the benzene rings of neighbouring mol­ecules, suggesting the existence of π–π stacking effects.

Dibrucinium sulfate hepta­hydrate

The crystal structure of dibrucinium sulfate­(VI) hepta­hydrate, 2C₂₃H₂₇N₂O₄⁺·SO₄²⁻·7H₂O, has been determined. The components are packed in layers. Puckered brucinium sheets are separated by layers consisting of hydrogen-bonded disordered sulfate(VI) anions and water mol­ecules. Both layers, the cationic together with the anionic/water, are linked by N—H⁺...O⁻ and O—H...O hydrogen bonds.