Crystal structures of cocrystals of 2,7-dihydroxy-naphthalene with isoniazid and piracetam

Cocrystals of 2,7-dihydroxynaphthalene (DHN, or naphthalene-2,7-diol) with isoniazid (pyridine-4-carbohydrazide) (INH), denoted DHN-INH [C10H8O2 center dot-C6H7N3O, (I)], and piracetam [2-(2-oxopyrrolidin-1-yl)acetamide] (PIR), denoted DHN-PIR [C10H8O2 center dot C6H10N2O2, (II)], were obtained by the solvent-assisted grinding method and characterized by IR spectroscopy, powder X-ray diffraction and single-crystal X-ray diffraction. Cocrystal (I) crystallized in the triclinic space group P (1) over bar and showed a 2:2 stoichiometry. DHN and INH molecules are connected by O-H center dot center dot center dot N(pyridine) and O-H center dot center dot center dot N(hydrazide) hydrogen bonds. Cocrystal (II) crystallized in the space group Pca2(1) with a 1:1 stoichiometry. DHN and PIR molecules are connected by O-H center dot center dot center dot O=C hydrogen bonds. The supramolecular architecture of cocrystal (I) showed interlinked supramolecular tapes; meanwhile, in cocrystal (II), interlinked supramolecular sheets were observed.

Automated summary

Two cocrystals (DHN-INH and DHN-PIR) crystallized in different space groups and connected molecules through different hydrogen bonding patterns. The supramolecular architecture showed different forms in the two cocrystals, with interlinked supramolecular tapes in one and interlinked supramolecular sheets in the other.