Two succinic acid derivatives of 2-ethyl-6-methyl­pyridin-3-ol

Crystals of bis(2-ethyl-3-hy­droxy-6-methyl­pyridinium) succin­ate-succin­ic acid (1/1), C₈H₁₂NO⁺·0.5C₄H₄O₄^2-·0.5C₄H₆O₄, (I), and 2-ethyl-3-hy­droxy-6-methyl­pyridinium hydrogen suc­cinate, C₈H₁₂NO⁺·C₄H₅O₄^-, (II), were obtained by reaction of 2-ethyl-6-methyl­pyridin-3-ol with succinic acid. The succinate anion and succinic acid mol­ecule in (I) are located about centres of inversion. Inter­molecular O-H...O, N-H...O and C-H...O hydrogen bonds are responsible for the formation of a three-dimensional network in the crystal structure of (I) and a two-dimensional network in the crystal structure of (II). Both structures are additionally stabilized by [pi]-[pi] inter­actions between symmetry-related pyridine rings, forming a rod-like cationic arrangement for (I) and cationic dimers for (II).