organic compounds
Open access
In the title adduct, C7H5NO4·0.5C6H6N4, the complete biimidazole molecule is generated by a crystallographic inversion centre. In the crystal, N—HO and O—HN hydrogen bonds connects the 4-nitrobenzoic acid and 2,2′-biimidazole units, affording multi-dimensional frameworks with graph-set descriptor R22(9).
organic compounds
Open access
In the title compound, C20H22N2O4, the dihedral angle between the roughly planar dihydropyridine ring (r.m.s. deviation = 0.092 Å) and the benzene ring is 87.09 (6)°. One of the ethoxy side chains is disordered over two orientations in a 0.669 (14):0.331 (14) ratio. In the crystal, molecules are linked by N—HN hydrogen bonds, generating chains.