6-Bromo-1-methyl-4-[2-(1-phenyl­ethyl­idene)hydrazinyl­idene]-3,4-dihydro-1H-2λ⁶,1-benzothia­zine-2,2-dione

In the title compound, C₁₇H₁₆BrN₃O₂S, the dihedral angle between the aromatic rings is 1.24 (15)° and the C=N—N=C torsion angle is 167.7 (3)°. The conformation of the thia­zine ring is an envelope, with the S atom displaced by 0.805 (3) Å from the mean plane of the other five atoms (r.m.s. deviation = 0.027 Å). In the crystal, C—H...O inter­actions link the mol­ecules into C(10) [010] chains. A weak C—H...π inter­action is also observed.

3-Chloro-1-methyl-4-[2-(3-phenyl­allyl­idene)hydrazinyl­idene]-3,4-dihydro-1H-2λ⁶,1-benzothia­zine-2,2-dione

In the title compound, C₁₈H₁₆ClN₃O₂S, the dihedral angle between the aromatic rings is 4.81 (2)° and the alkyl chain takes on an extended conformation [N—C—C—C = 179.2 (4)°]. The conformation of the thia­zine ring is an envelope, with the S atom displaced by −0.805 (3) Å from the mean plane of the other five atoms (r.m.s. deviation = 0.046 Å). The Cl atom is an axial conformation and is displaced by 1.761 (4) Å from the thia­zine ring plane. In the crystal, inversion dimers linked by pairs of C—H...O inter­actions generate R₂²(20) loops and further C—H...O hydrogen bonds link the dimers into (001) sheets. Weak aromatic π–π stacking inter­actions [centroid–centroid separations = 3.870 (3) and 3.883 (3) Å] are also observed.

1-Ethyl-4-{2-[1-(4-methyl­phen­yl)ethyl­idene]hydrazinyl­idene}-3,4-dihydro-1H-2λ⁶,1-benzothia­zine-2,2-dione

In the title compound, C₁₉H₂₁N₃O₂S, the dihedral angle between the aromatic rings is 6.7 (2)° and the C=N—N=C torsion angle is 178.0 (2)°. The conformation of the thia­zine ring is an envelope, with the S atom displaced by 0.802 (2) Å from the mean plane of the other five atoms (r.m.s. deviation = 0.022 Å). In the crystal, mol­ecules are linked by C—H...O inter­actions, generating C(5) chains propagating in [010]. A weak C—H...π inter­action is also observed.

3-Chloro-4-[2-(4-chloro­benzyl­idene)hydrazinyl­idene]-1-methyl-3,4-dihydro-1H-2λ⁶,1-benzothia­zine-2,2-dione

In the title compound, C₁₆H₁₃Cl₂N₃O₂S, the dihedral angle between the aromatic rings is 6.62 (2)° and the C=N—N=C torsion angle is 176.2 (4)°. The thia­zine ring shows an envelope conformation, with the S atom displaced by 0.633 (6) Å from the mean plane of the other five atoms (r.m.s. deviation = 0.037 Å). The Cl atom is an an axial conformation and is displaced by 2.015 (6) Å from the thia­zine ring plane. In the crystal, mol­ecules are linked by C—H...O inter­actions, generating a three-dimensional network. Very weak aromatic π–π stacking inter­actions [centroid–centroid separations = 3.928 (2) Å] are also observed.