3-[Hy­droxy(3-meth­oxy­phen­yl)methyl­idene]-2-(2-oxo-2-phenyl­eth­yl)-3,4-dihydro-2H-1λ6,2-benzothia­zine-1,1,4-trione

In the title mol­ecule, C24H19NO6S, the heterocyclic thia­zine ring adopts a half-chair conformation with the S and N atoms displaced by 0.180 (5) and 0.497 (5) Å, respectively, on opposite sides of the mean plane formed by the remaining ring atoms. The benzene rings of the benzothia­zine unit and the meth­oxy­phenyl group are almost coplanar, with the dihedral angle between the mean planes of these rings being 5.9 (2)°, while the benzene ring of the 2-oxo-2-phenyl­ethyl group is inclined at 79.68 (11) and 81.01 (10)°, respectively, to these rings. The mol­ecular structure is consolidated by intra­molecular O—H⋯O and C—H⋯N inter­actions, and the crystal packing is stabilized by weak C—H⋯O hydrogen bonds

N-Acetonylsaccharin

In the title compound [systematic name: 2-(2-oxoprop­yl)-1,2-benzothia­zol-3(2H)-one 1,1-dioxide], C10H9NO4S, the benzo­thia­zole unit is essentially planar [maximum deviation = 0.0490 (9) Å for the S atom] and the oxopropyl group is inclined at an angle 75.61 (8)° with respect to its mean plane. In the crystal, mol­ecules are held together by weak inter­molecular C—H⋯O non-classical hydrogen bonds, resulting in centrosymmetric dimeric units, forming 14-membered ring systems which may be described as R 2 2(14) ring motifs. Moreover, mol­ecules lying about inversion centers show π–π inter­actions, with centroid–centroid separations between the benzene rings of 3.676 (2) Å

2-[(Methyl­sulfan­yl)meth­yl]-1,2-benz­isothia­zol-3(2H)-one 1,1-dioxide

In the title mol­ecule, C9H9NO3S2, the essentially planar benzisothia­zole ring system and the C—S—C atoms of the methyl­sulfanyl side chain form an angle of 64.45 (7)°. The structure is devoid of any classical hydrogen bonding. However, weak non-classical inter- and intra­molecular hydrogen bonds of the type C—H⋯O are present

N-Benzyl-4-hy­droxy-2-methyl-1,1-dioxo-2H-1λ6,2-benzothia­zine-3-carboxamide

In the title mol­ecule, C17H16N2O4S, the heterocyclic thia­zine ring adopts a half-chair conformation, with the S and N atoms displaced by 0.546 (4) and 0.281 (4) Å, respectively, on opposite sides of the mean plane formed by the remaining ring atoms. The mol­ecular structure is stabilized by an intra­molecular O—H⋯O hydrogen bond. The two aromatic rings are inclined to one another by 42.32 (11)°. In the crystal, mol­ecules are linked by pairs of N—H⋯O hydrogen bonds, forming inversion dimers. The dimers are linked via a series of C—H⋯O inter­actions, leading to the formation of a three-dimensional network

4-Hy­droxy-2-methyl-1,1-dioxo-N-phenyl-2H-1λ6,2-benzothia­zine-3-carboxamide

In the title mol­ecule, C16H14N2O4S, the thia­zine ring adopts a twist chair conformation with the N and adjacent C atom displaced by 0.966 (3) and 0.386 (4) Å, respectively, on the same side of the mean plane formed by the remaining ring atoms. The dihedral angle between the mean planes of the benzene rings is 37.65 (10)°. The mol­ecular structure features an intra­molecular O—H⋯O hydrogen bond, which generates an S(6) ring. In the crystal, mol­ecules are linked by N—H⋯O and C—H⋯O hydrogen bonds

N-Saccharinylmethyl ether

In the title mol­ecule [systematic name: 1,1,1′,1′-tetra­oxo-2,2′-(oxydimethyl­ene)bi(1,2-benzothia­zol-3-one)], C16H12N2O7S2, the benzisothia­zole ring systems are individually planar [maximum deviations of 0.0497 (13) and 0.0195 (19) Å] and their mean planes are inclined at a dihedral angle of 62.76 (4)°. The crystal structure is stabilized by weak inter­molecular C—H⋯O inter­actions. Two O atoms bonded to two S atoms and four aryl H atoms belonging to two symmetry-related mol­ecules lying about an inversion center form a hydrogen-bonded 10-membered ring with graph-set notation R 4 2(10)

2-Methyl-1,2-benzisothia­zol-3(2H)-one 1,1-dioxide

All atoms of the title mol­ecule, C8H7NO3S, except the two oxide O atoms and two H atoms of the methyl group, lie on a crystallographic mirror plane. The crystal structure is stabilized by weak inter- and intra­molecular C—H⋯O hydrogen bonds

N-(2-Chloro­phen­yl)-4-hydr­oxy-2H-1,2-benzothia­zine-3-carboxamide 1,1-dioxide

In the title compound, C15H11ClN2O4S, there are two independent mol­ecules in the asymmetric unit, in which the heterocyclic thia­zine rings in both mol­ecules adopt half-chair conformations. The conformations about the C—C and C—N bonds in the central C—C—N—C chain in both mol­ecules are all EZ. There are strong intra­molecular O—H⋯O and N—H⋯N hydrogen bonds resulting in graph-set patterns S(6) and S(5) for the oxo and amino rings, in addition to intra­molecular N—H⋯Cl inter­actions. In the crystal structure, mol­ecules are linked by inter­molecular O—H⋯O and N—H⋯O hydrogen bonds into chains along [100]

4-Hy­droxy-2-methyl-1,1-dioxo-2H-1λ6,2- benzothia­zine-3-carb­oxy­lic acid hemihydrate

In the title compound, C10H9NO5S·0.5H2O, two geometrically different organic mol­ecules are present. The benzene rings and the carboxyl­ate groups are oriented at dihedral angles of 13.44 (4) and 21.15 (18)°. In both mol­ecules, an intra­molecular O—H⋯O hydrogen bond generates an S(6) ring. In the crystal, both moleucles form inversion dimers linked by pairs of O—H⋯O hydrogen bonds to generate R 2 2(8) loops. The dimers are consolidated into chains extending along [100] by bridging O—H⋯O hydrogen bonds from the water mol­ecule. A weak C—H⋯O hydrogen bond also occurs

2,2′-(4-Methyl-4H-1,2,4-triazole-3,5-di­yl)dibenzene­sulfonamide

In the title compound, C15H15N5O4S2, the dihedral angles between the central 1,2,4-triazole ring and the pendant benzene rings are 55.61 (10) and 68.59 (10)°; the dihedral angle between the benzene rings is 63.66 (9)°. Intra­molecular N—H⋯N and N—H⋯O hydrogen bonds generate S(7) and S(12) rings, respectively. In the crystal, sheets extending in the (101) plane arise, with the mol­ecules linked by C—H⋯O, N—H⋯N and N—H⋯O inter­actions. A C—H⋯π inter­action further consolidates the structure