3-(4-Methoxybenzyl)-1,5-benzo­thiazepin-4(5H)-one

In the title compound, C₁₇H₁₅NO₂S, the thia­zepine ring adopts a slightly distorted twist-boat conformation. The dihedral angle between the mean plane of the benzo­thia­zepin ring system and the benzene ring is 65.7 (1)°. In the crystal, pairs of N—H...O hydrogen bonds link inversion-related mol­ecules into dimers, generating R₂²(8) ring motifs. These dimers are further linked by C—H...π and π–π inter­actions [inter-centroid distance between the benzene rings of the benzo­thia­zepine unit = 3.656 (3) Å] into a three-dimensional supra­molecular network.

(Z)-3-(3,4-Di­meth­oxy­benz­yl)-1,5-benzo­thia­zepin-4(5H)-one

In the title compound, C₁₈H₁₇NO₃S, the thia­zepine ring adopts a slightly distorted twist-boat conformation. The dihedral angle between the mean plane of the benzo­thia­zepin ring system and the benzene ring is 60.3 (1)°. In the crystal, mol­ecules are linked by two pairs of inversion-related N—H...O and C—H...O hydrogen bonds, generating alternating R₂²(8) and R₂²(6) ring motifs, respectively, in a zigzag supra­molecular chain that runs along the c axis. These chains stack along the a axis via S...C [3.424 (2) Å] contacts. A three-dimensional supra­molecular network is consolidated by C—H...π and π–π inter­actions [inter-centroid distance between di­meth­oxy­benzene rings = 3.815 (1) Å]. The crystal studied was a non-merohedral twin, with a refined value of the minor twin fraction of 0.2477 (6) .