Sulfonamide−Pyridine-N-oxide Cocrystals

Hydrogen-bond motifs for the supramolecular synthesis of sulfonamide−pyridine-N-oxide complexes were derived from the analysis of cocrystal structures of aryl sulfonamides and pyridine-N-oxides. The sulfonamide NH donor persistently interacts with the N-oxide acceptor via a N−H···O hydrogen bond, though the exact geometry of the motif, such as discrete (D), infinite chain C(4), cyclic motifs R42(8) or R22(4), varies from structure to structure. Surprisingly, the two-point R22(8) cyclic motif of N−H···O and C−H···O hydrogen bonds, analogous to the heterosynthon in carboxamide−pyridine-N-oxide cocrystals, was not observed in sulfonamide−N-oxide cocrystals. The utility of this model study is demonstrated by making cocrystals of Furosemide with 4,4′-bipyridine-N,N′-dioxide and isonicotinamide-N-oxide.