Crystal structure, Hirshfeld surface analysis and DFT calculations of (E)-3-[1-(2-hy-droxy-phenyl-anilino)ethyl-idene]-6-methyl-pyran-2,4-dione.

The asymmetric unit of the title compound, C14H13NO4, contains three independent mol-ecules, which differ slightly in conformation. Each contains an intra-molecular N-H⋯O hydrogen bond. In the crystal, O-H⋯O hydrogen bonds form chains of mol-ecules, which are linked into corrugated sheets parallel to (03) plane by C-H⋯O hydrogen bonds together with π inter-actions between the carbonyl groups and the 2-hy-droxy-phenyl rings. The layers are linked by further C-H⋯O hydrogen bonds. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H (49.0%), H⋯O/O⋯H (28.3%) and H⋯C/C⋯H (10.9%) inter-actions. van der Waals inter-actions are the dominant inter-actions in the crystal packing. Moreover, density functional theory (DFT) optimized structures at the B3LYP/ 6-311 G(d,p) level are compared with the experimentally determined mol-ecular structure in the solid state. The HOMO-LUMO behavior was elucidated to determine the energy gap of 4.53 eV.

1,1''-Bis(prop-2-en-1-yl)-1,1'',2,2''-tetra-hydro-dispiro-[indole-3,7'-[6,9]diaza-tricyclo-[7.3.0.0(2,6)]dodecane-8',3''-indole]-2,2''-dione.

The mol-ecule of the title compound, C(30)H(32)N(4)O(2), lies on a twofold rotation axis that passes through the mid-points of the C-C bonds of the piperazine ring, which adopts a chair conformation. The pyrrolidine ring that is fused to the piperazine ring adopts an envelope conformation (in which the N atom represents the flap). The indoline fused-ring system is nearly planar (r.m.s. deviation = 0.044 Å); the two symmetry-related indoline fused-rings systems are aligned at 71.44 (3)°.

5,5''-Dibromo-1,1''-bis-(prop-2-en-1-yl)-1,1'',2,2''-tetra-hydro-dispiro-[indole-3,7'-[6,9]diaza-tricyclo-[7.3.0.0(2,6)]dodecane-8',3''-indole]-2,2''-dione.

In the mol-ecule of the title compound, C(30)H(30)Br(2)N(4)O(2), the piperazine ring adopts a chair conformation. The pyrrolidine rings that are fused to the piperazine ring adopt envelope conformations (in which the N atom represents the flap). The indoline fused-ring systems are nearly planar (r.m.s. deviations = 0.009 and 0.019 Å); the two fused rings are aligned at 60.63 (6)°.

1,1'-Dibenzyl-5,5''-dichloro-1,1'',2,2''-tetra-hydro-dispiro-[indole-3,7'-[6,9]diaza-tricyclo-[7.3.0.0(2,6)]dodecane-8',3''-indole]-2,2''-dione.

In the title compound, C(38)H(34)Cl(2)N(4)O(2), the piperazine ring adopts a chair conformation. The pyrrolidine rings that are fused to the piperazine ring adopt envelope conformations (in which the C atoms connecting the two rings represent the flap). The indoline ring systems are approximately planar (r.m.s. deviations = 0.026 and 0.034 Å) and are aligned at a dihedral angle of 54.98 (3)°.