(E)-4-[(2-Carbamoylhydrazinylidene)methyl]-3-hydroxy-5-hydroxymethyl-2- methylpyridin-1-ium nitrate

Abstract

The title compound, C9H13N4O3+·NO3-, is the first structurally characterized Schiff base derived from semicarbazide and pyridoxal. Unusually for an unsubstituted semicarbazone, the compound adopts a syn conformation, in which the carbonyl O atom is in a cis disposition relative to the azomethine N atom. This arrangement is supported by a pair of hydrogen bonds between the organic cation and the nitrate anion. The cation is essentially planar, with only a hydroxymethyl O atom deviating significantly from the mean plane of the remaining atoms (r.m.s. deviation of the remaining non-H atoms = 0.01 Å). The molecules are linked into flat layers by N - H⋯O and C - H⋯O hydrogen bonds. O - H⋯O hydrogen bonds involving the hydroxymethyl group as a donor interconnect the layers into a three-dimensional structure. © 2013 International Union of Crystallography.