Stable and reproducible supramolecular motif in the crystal structure of sulfonamides of the benzothiazine series fused to an epoxybornane moiety

Abstract

The crystal structures of four sulfonamides of the benzothiazine series, fused to an epoxidized norbornane moiety and containing various substituents in the para position of the aromatic ring, were determined. Despite the different volume and acceptor/donor properties of substituents (hydrogen, a methyl group, a cyano group, fluorine), these compounds form isostructural crystals. The main supramolecular motif of these crystals consists of heterochiral chains, which run along a glide plane and are formed via hydrogen bonds between the axial oxygen atom of the sulfonyl group and the amino-group nitrogen atom. The chains are cross-linked to form a crystal structure through C—H…O interactions between the hydrogen atom at the epoxide ring and the equatorial sulfonyl oxygen atom.