Structures of Four Organic Acid-base Adducts From 4-aminoantipyrine, 3,5-dinitrobenzoic Acid, Anthranilic Acid, 5-nitrosalicylic Acid, and 1, 5-naphthalenedisulfonic Acid

Abstract Cocrystallization of 4-aminoantipyrine which is widely used in the field of pharmacological applications with four organic acids yielded acid-base adducts: (4-aminoantipyrine): (3,5-dinitrobenzoic acid) [(HL+) • (dna−), dna− = 3,5-dinitrobenzoate] (1), (4-aminoantipyrine): (anthranilic acid) [(L) • (Hata), Hata = anthranilic acid] (2), (4-aminoantipyrine)2: (5-nitrosalicylic acid)3: H2O [(HL+)2 • (nsa−)2 • (Hnsa) • H2O, nsa− = 5-nitrosalicylate] (3) and (4-aminoantipyrine)2: (1,5-naphthalenedisulfonic acid) [(HL+)2 • (nds2−), nds2− = 1, 5-naphthalenedisulfonate] (4). The four adducts have been characterised by elemental analysis, infrared spectroscopy and X-ray single crystal diffraction, their melting points were also gauged. Their structural and supramolecular aspects are fully analyzed. XRD analysis indicated that 1, 3 and 4 are organic salts, 2 is a cocrystal. The crystal packing is mediated by the strong charge-assisted or neutral N-H⋯O hydrogen bond. Apart from the N-H⋯O hydrogen bonds, the O-H•••O hydrogen bonds are also present at 2-3. Further inspection into the crystal packing indicate that a different family of additional CH⋯O/CH3⋯O, CH⋯π/CH3⋯π and OH⋯π/O•••π contacts contributes to the stabilization and expansion of the final 2D/3D structures.