New solid forms of the diuretic compound 4-Chloro Salicylic Acid-5-Sulfonamide

Abstract

Four multi-component solid forms of the diuretic compound 4-Chloro Salicylic Acid-5-Sulfonamide (CSAS), including two hydrates (named as 2-hydrate, 3-hydrate), one cocrystal with benzoic acid (named as 4-cocrystal) and a cocrystal-solvate of 4,4’ bipyridine (BIP) with 1,4 dioxane (denoted as 5-multicomp) were successfully obtained. The crystal structures were determined by X-ray single crystal technique and further, the structural characterization was made by XRPD and FT-IR. The total lattice energy, which can be partitioned in Coulombic, polarization, dispersion and repulsion components has been computed using the atom-atom Coulomb-London-Pauli forcefield approximation (AA-CLP). For the two hydrates, the diuretic molecules and water molecules are connected to each other via N-H…O and O-H…O hydrogen bonds. The cocrystal with benzoic acid has the diuretic molecule linked to benzoic acid in a 1:1 stoechiometric manner via carboxyl-carboxyl O-H…O hydrogen bonds, forming a R22(8) homosynthon. The multicomponent cocrystal-solvate system is stabilized by a combination of C-H…O and N-H…O hydrogen bonds between the solvent, 4,4’ bipyridine and the starting compound.