The influence of the substituents in the crystals of the title compounds has not made any significant effect on the crystal packing and inter­molecular hydrogen bonds. The validity of chlorine–methyl exchange rule is confirmed.

In the title compound, diethyl 2,2-dioxo-4-(thiophen-2-yl)-1-[(thiophen-2-yl)methyl]-3,4,6,7,8,8a-hexahydro-1H-pyrrolo[2,1-c][1,4]thiazine-1,3-dicarboxylate, C22H28NO6S3, the pyrrolo ring is in an envelope conformation while the thiazine ring adopts a near chair conformation. The dihedral angles between the thiazine ring and the methylthienyl, thienyl and pyrrolo rings are 64.0 (2), 87.92 (7) and 5.6 (2)°, respectively. In the crystal, the molecules are linked by weak C—H...O hydrogen bonds. A Hirshfeld surface analysis was performed to investigate the intermolecular interactions. Disorder of the methylthienyl group with site occupancies of 0. 792 (3) and 0.208 (3) is observed

In the title compound, C23H23Cl2N3O2, the pyrroline ring adopts an envelope conformation and the piperidinone ring assumes a slightly twisted chair form. In the crystal, inversion dimers linked by pairs of N—H⋯O hydrogen bonds generate an R 2 8 graph-set motif and a short Cl⋯Cl contact of 3.478 (1) Å occurs.

The title compound, C26H29N3O2, crystallizes with two mol­ecules in the asymmetric unit, having C—H⋯O inter­actions between them and resulting in a dimer characterized by an R 2 2(11) motif. These dimers are linked into an ABABAB chain via N—H⋯O, N—H⋯N and C—H⋯O built edge-fused R 1 2(5) and R 2 2(7) motifs. This chain is linked to its inversion-related partner via N—H⋯O bonds with an R 2 2(8) motif and leads to a double chain extending along the b axis characterized by an R 6 6(36) motif across the inversion centres. The methyl group of the phenyl ring and the oxindole of mol­ecule A and B are involved in C—H⋯π inter­actions. One C atom of the pyrrolizine ring of mol­ecule A and its attached H atoms show positional disorder, the major and minor components being in the ratio 0.706 (7):0.294 (7).

No abstract