Different supramolecular architectures mediated by different weak interactions in the crystals of three N-aryl-2,5-dimethoxybenzenesulfonamides

The synthesis and evaluation of the pharmacological activities of mol­ecules containing the sulfonamide moiety have attracted interest as these compounds are important pharmacophores. The crystal structures of three closely related N-ar­yl-2,5-di­meth­oxy­benzene­sulfonamides, namely N-(2,3-di­chloro­phen­yl)-2,5-di­meth­oxy­benzene­sulfonamide, C14H13Cl2NO4S, (I), N-(2,4-di­chloro­phen­yl)-2,5-di­meth­oxy­benzene­sulfonamide, C14H13Cl2NO4S, (II), and N-(2,4-di­methyl­phen­yl)-2,5-di­meth­oxy­benzene­sulfonamide, C16H19NO4S, (III), are described. The asymmetric unit of (I) consists of two symmetry-independent mol­ecules, while those of (II) and (III) contain one mol­ecule each. The mol­ecular conformations are stabilized by different intra­molecular inter­actions, viz. C—H⋯O inter­actions in (I), N—H⋯Cl and C—H⋯O inter­actions in (II), and C—H⋯O inter­actions in (III). The crystals of the three compounds display different supra­molecular architectures built by various weak inter­molecular inter­actions of the types C—H⋯O, C—H⋯Cl, C—H⋯π(ar­yl), π(ar­yl)–π(ar­yl) and Cl⋯Cl. A detailed Hirshfeld surface analysis of these compounds has also been conducted in order to understand the relationship between the crystal structures. The dnorm and shape-index surfaces of (I)–(III) support the presence of various inter­molecular inter­actions in the three structures. Analysis of the fingerprint plots reveals that the greatest contribution to the Hirshfeld surfaces is from H⋯H contacts, followed by H⋯O/O⋯H contacts. In addition, comparisons are made with the structures of some related compounds. Putative N—H⋯O hydrogen bonds are observed in 29 of the 30 reported structures, wherein the N—H⋯O hydrogen bonds form either C(4) chain motifs or R22(8) rings. Further comparison reveals that the characteristics of the N—H⋯O hydrogen-bond motifs, the presence of other inter­actions and the resultant supra­molecular architecture is largely decided by the position of the substituents on the benzene­sulfonyl ring, with the nature and position of the substituents on the aniline ring exerting little effect. On the other hand, the crystal structures of (I)–(III) display several weak inter­actions other than the common N—H⋯O hydrogen bonds, resulting in supra­molecular architectures varying from one- to three-dimensional depending on the nature and position of the substituents on the aniline ring.