Crystal structures of three 1-oxo-1,2-di-hydro-naphthalene derivatives: dimethyl 4-(4-meth-oxy-phen-yl)-2-(4-methyl-phen-yl)-1-oxo-1,2-di-hydro-naphthalene-2,3-di-carboxyl-ate, dimethyl 1-oxo-2-(pyren-4-yl)-4-(thio-phen-2-yl)-1,2-di-hydro-naphthalene-2,3-di-carboxyl-ate and ethyl 1-oxo-2-phenyl-2,4-bis-(thio-phen-2-yl)-1,2-di-hydro-naphthalene-3-carboxyl-ate.

In the title 1-oxo-1,2-di-hydro-naphthalene derivatives, C28H24O6, (I), C34H22O5S, (II), and C27H20O3S2, (III), the cyclo-hexa-1,3-diene rings of the 1,2-di-hydro-naphthalene ring systems adopt half-chair, boat and half-chair conformations, respectively. The carbonyl O atoms attached to the di-hydro-naphthalene ring systems are each significantly deviated from the mean plane of the 1,2-di-hydro-naphthalene ring system, by 0.6162 (12) Šin (I), 0.6016 (16) Šin (II) and 0.515 (3) Šin (III). The mean planes of the 1,2-di-hydro-naphthalene ring systems make dihedral angles of 85.83 (3), 88.19 (3) and 81.67 (8)°, respectively, with the methyl-phenyl ring in (I), the pyrene ring in (II) and the phenyl ring in (III). In (I), the mol-ecular structure is stabilized by an intra-molecular C-H⋯O hydrogen bond, generating an S(6) ring motif. In the crystal of (I), mol-ecules are linked by an inter-molecular C-H⋯O hydrogen bond, which generates a C(8) zigzag chain running along [100]. Adjacent chains are further connected by C-H⋯π and offset π-π inter-actions [centroid-centroid distance = 3.6572 (9) Å], forming a double-chain structure. In the crystals of (II) and (III), mol-ecules are linked into chain structures by offset π-π inter-actions with centroid-centroid distances of 3.5349 (12) and 3.8845 (13) Šfor (II) and 3.588 (2) Šfor (III). In (II) and (III), the thio-phene rings are orientationally disordered over two sites, with occupancy ratios of 0.69:0.31 for (II), and 0.528 (4):0.472 (4) and 0.632 (5):0.368 (5) for (III).

Crystal structures of two new carbazole derivatives: 12-(4-nitro-phen-yl)-7-phenyl-sulfonyl-7H-benzofuro[2,3-b]carbazole and 2-methyl-4-(4-nitro-phen-yl)-9-phenyl-sulfonyl-9H-thieno[2,3-b]carbazole.

The title compounds, C30H18N2O5S, (I), and C27H18N2O4S2, (II), are carbazole derivatives with a phenyl-sulfonyl group and a nitro-phenyl group attached to the carbazole moiety in identical positions in both mol-ecules. A benzo-furan ring system in (I) and a methyl-thio-phene ring in (II) are fused with the respective carbazole moieties on the same sides. The mean plane of the carbazole ring system makes a dihedral angle of 3.17 (7)° with the benzo-furan ring system in (I) and a dihedral angle of 3.39 (11)° with the methyl-thio-phene ring in (II), implying that both fused units are essentially planar. The mean planes of the carbazole ring systems in both the compounds are almost orthogonal to the respective nitro-substituted phenyl rings, making dihedral angles of 75.64 (10) and 77.63 (12)° in compounds (I) and (II), respectively. In (I), the phenyl-sulfonyl ring system is positionally disordered with a refined occupancy ratio of 0.63 (2):0.37 (2). In both compounds, the mol-ecular structures are stabilized by intra-molecular C-H⋯O hydrogen bonds, generating S(6) ring motifs with the sulfone group O atoms. In the crystal of compound (I), mol-ecules are linked by pairs of C-H⋯O hydrogen bonds, which generate R22(18) inversion dimers, and inter-connected by C(14) chains running along the c-axis direction, whereas in compound (II), the C-H⋯O hydrogen bonds generate R43(37) ring motifs. In the crystals of both compounds, C-H⋯O hydrogen-bonded sheets are formed lying parallel to (10-1). In addition, C-H⋯π and offset π-π inter-actions [inter-centroid distance = 3.7158 (14) Šin (I) and 3.9040 (15) Šin (II)] are also present in the crystals of both compounds.

Crystal structures of three carbazole derivatives: 12-ethyl-7-phenyl-sulfonyl-7H-benzofuro[2,3-b]carbazole, (1), 2-(4,5-dimeth-oxy-2-nitro-phen-yl)-4-hy-droxy-9-phenyl-sulfonyl-9H-carbazole-3-carbaldehyde, (2), and 12-phenyl-7-phenyl-sulfonyl-7H-benzofuro[2,3-b]carbazole, (3).

The three title compounds, C26H19NO3S, (1), C27H20N2O8S, (2), and C30H19NO3S, (3), are carbazole derivatives, where (1) and (3) are heterocycle-containing carbazoles with a benzo-furan moiety fused to a carbazole unit. In (2), a di-meth-oxy-nitro-phenyl ring is attached to the carbazole moiety. In the three derivatives, a phenyl-sulfonyl group is attached to the N atom of the carbazole unit. Compound (1) crystallizes with two independent mol-ecules in the asymmetric unit (A and B). The carbazole skeleton in the three compounds is essentially planar. In compound (1), the benzene ring of the phenyl-sulfonyl moiety is almost orthogonal to the carbazole moiety, with dihedral angles of 85.42 (9) and 84.52 (9)° in mol-ecules A and B, respectively. The benzene ring of the phenyl-sulfonyl group in compounds (2) and (3) are inclined to the carbazole moiety, making dihedral angles of 70.73 (13) and 81.73 (12)°, respectively. The S atom has a distorted tetra-hedral configuration in all three compounds. In the crystals, C-H⋯O hydrogen bonds give rise to R22(12) inversion dimers for compound (1), and to R22(24) inversion dimers and R44(40) ring motifs for compound (2). The crystal packing in (1) also features C-H⋯π and π-π inter-actions [shortest inter-centroid distance = 3.684 (1) Å], leading to supra-molecular three-dimensional aggregation. In the crystal of compound (2), the combination of the various C-H⋯O hydrogen bonds leads to the formation of a three-dimensional network. In the crystal of compound (3), mol-ecules are linked by C-H⋯O hydrogen bonds, forming chains running parallel to the a axis, and the chains are linked by C-H⋯π inter-actions, forming corrugated sheets parallel to the ab plane.

Crystal structure of 6-(p-tol-yl)benzo[b]naphtho[2,3-d]thio-phene and of an ortho-rhom-bic polymorph of 7-phenyl-anthra[2,3-b]benzo[d]thio-phene.

The title compounds, C23H16S, (I), and C26H16S, (II), are benzo-thio-phene derivatives in which the benzo-thio-phene moiety is fused with a naphthalene ring system in (I), and with an anthracene ring system in (II). In (I), the mean plane of the benzo-thio-phene ring system makes a dihedral angle of 2.28 (6)° with the naphthalene ring system, and a dihedral angle of 1.28 (6)° with the anthracene ring system in (II), showing that the fused units are essentially planar. In (I), the 4-methyl-benzene ring substituent makes a dihedral angle of 71.40 (9)° with the naphthalene ring system, while the phenyl ring substituent in (II) makes a dihedral angle of 67.08 (12)° with the anthracene ring system. In the crystals of both compounds, mol-ecules are linked by C-H⋯π inter-actions, leading to the formation of slabs parallel to (001) in (I) and to zigzag chains along [001] in (II). There are also offset π-π inter-actions present within the slabs in (I). In the crystal of (II), they link the chains, forming sheets parallel to (010). The triclinic polymorph of compound (II) has been reported [Sivasakthikumaran et al., (2012 ▸). J. Org. Chem.77, 9053-9071].

Crystal structure of 3-[(E)-(2-hy-droxy-3-meth-oxy-benzyl-idene)amino]-1-methyl-1-phenyl-thio-urea.

In the asymmetric unit of the title compound, C16H17N3O2S, there are two independent mol-ecules (A and B), which show an E conformation with respect to the C=N bond. An intra-molecular O-H⋯N hydrogen bond with an S(6) motif stabilizes the mol-ecular structure. The terminal phenyl and benzene rings are almost orthogonal to each other, the dihedral angle being 87.47 (13)° for mol-ecule A and 89.86 (17)° for mol-ecule B. In the crystal, weak bifurcated N-H⋯(O,O) hydrogen bonds link the two independent mol-ecules, forming a supra-molecular chain with a C (2) 1(14)[R (2) 1(5)] motif along the b axis. A weak C-H⋯O inter-action is also observed in the chain.

Crystal structures and conformational analyses of three pyranochromene derivatives.

The title compounds, C27H20O6, (I) [systematic name: methyl 7-oxo-14-phenyl-1H,7H,14H-pyrano[3,2-c:5,4-c']dichromene-14a(6bH)-carboxyl-ate], C24H22O5, (II) [systematic name: methyl 1-oxo-6-phenyl-2,3,4,12b-tetra-hydro-1H,6H-chromeno[3,4-c]chromene-6a(7H)-carboxyl-ate], and C25H23N3O4, (III) [systematic name: 6-(4-ethyl-phen-yl)-2,4-dimethyl-1,3-dioxo-2,3,4,12b-tetra-hydro-1H,6H-chromeno[4',3':4,5]pyrano[2,3-d]pyrimidine-6a(7H)-carbo-nitrile], are pyran-ochromene derivatives. The central pyran rings (B) of compounds (I) and (III) adopt half-chair conformations, whereas that of compound (II) adopts a sofa conformation. The pyran rings (A) of the chromene ring systems of compounds (II) and (III) adopt half-chair conformations, while that of compound (I) adopts a sofa conformation. The mean plane of the central pyran rings (B) make dihedral angles of 70.02 (6), 61.52 (6) and 69.12 (7)°, respectively, with the mean planes of the chromene moieties (C+A) of compounds (I), (II) and (III). The bicyclic coumarin ring system (C+A+B+E) in compound (I) is almost planar (r.m.s. deviation = 0.042 Å). The carbo-nitrile side chain in compound (III) is very nearly linear, with the C-C N angle being 176.6 (2)°. The cyclo-hexene ring (E), fused with the central pyran ring (B) in compound (II) adopts a sofa conformation. In the mol-ecular structures of compounds (II) and (III), there are C-H⋯O short contacts, which generate S(7) ring motifs. In the crystal structures of the title compounds, mol-ecules are linked by C-H⋯O hydrogen bonds, which generate mol-ecular sheets parallel to the ab plane, with R 4 (3)(28) loops in (I), inversion dimers with R 2 (2)(10) loops in (II) and chains along [010] with R 2 (2)(12) ring motifs in (III). In the crystal structures of (I) and (III), there are also C-H⋯π inter-actions present, leading to the formation of a three-dimensional framework in (II) and to sheets parallel to (101) in (III).

Crystal structures of three indole derivatives: 3-ethnyl-2-methyl-1-phenyl-sulfonyl-1H-indole, 4-phenyl-sulfonyl-3H,4H-cyclo-penta-[b]indol-1(2H)-one and 1-{2-[(E)-2-(5-chloro-2-nitro-phen-yl)ethen-yl]-1-phenyl-sulfonyl-1H-indol-3-yl}ethan-1-one chloro-form monosolvate.

The title compounds, C17H13NO2S, (I), C17H13NO3S, (II), and C24H17ClN2O5S·CHCl3, (III), are indole derivatives. Compounds (I) and (II) crystalize with two independent mol-ecules in the asymmetric unit. The indole ring systems in all three structures deviate only slightly from planarity, with dihedral angles between the planes of the pyrrole and benzene rings spanning the tight range 0.20 (9)-1.65 (9)°. These indole ring systems, in turn, are almost orthogonal to the phenyl-sulfonyl rings [range of dihedral angles between mean planes = 77.21 (8)-89.26 (8)°]. In the three compounds, the mol-ecular structure is stabilized by intra-molecular C-H⋯O hydrogen bonds, generating S(6) ring motifs with the sulfone O atom. In compounds (I) and (II), the two independent mol-ecules are linked by C-H⋯O hydrogen bonds and C-H⋯π inter-actions, while in compound (III), the mol-ecules are linked by C-H⋯O hydrogen bonds, generating R 2 (2)(22) inversion dimers.

Crystal structures and conformations of two Diels-Alder adduct derivatives: 1,8-bis-(thio-phen-2-yl)-14-oxa-tetra-cyclo-[6.5.1.0(2,7).0(9,13)]tetra-deca-2(7),3,5-trien-10-one and 1,8-diphenyl-14-oxa-tetra-cyclo[6.5.1.0(2,7).0(9,13)] tetra-deca-2,4,6-trien-10-one.

The title compounds, C21H16O2S2 (I) and C25H20O2 (II), are products of a tandem 'pincer' Diels-Alder reaction consisting of [2 + 2] cyclo-additions between benzo[c]furan and cyclo-penta-none. Each comprises a fused tetra-cyclic ring system containing two five-membered rings (in envelope conformations with the O atom as the flap) and six-membered rings (in boat conformations). In addition, two thio-phene rings in (I) and two phenyl rings in (II) are attached to the tetra-cyclic ring system. The cyclo-penta-none ring adopts a twisted conformation in (I) and an envelope conformation in (II). In (I), the thio-phene rings are positionally disordered over two sets of sites, with occupancy ratios of 0.901 (2):0.099 (2) and 0.666 (2):0.334 (2). In (II), the oxygen atom of the cyclo-penta-none ring is rotationally disordered over two sites with an occupancy ratio of 0.579 (4):0.421 (4). The mol-ecular structure of (I) is stabilized by an intra-molecular C-H⋯O hydrogen bond, which generates an S(7) ring motif. In the crystal, the mol-ecules are linked via weak C-H⋯O hydrogen bonds, which generate R (2) 2(16) ring motifs in (I) and C(8) chains in (II). In both structures, the crystal packing also features C-H⋯π inter-actions. The crystal studied of compound (I) was twinned by non-merohedry. The twin component is related by the twin law [-1 0 0 -0.101 1 -0.484 0 0 -1] operated by a twofold rotation axis parallel to the b axis. The structure of (I) was refined with a twin scale factor of 0.275 (2).

Crystal structures of two hydrazinecarbo-thio-amide derivatives: (E)-N-ethyl-2-[(4-oxo-4H-chromen-3-yl)methyl-idene]hydrazinecarbo-thio-amide hemi-hydrate and (E)-2-[(4-chloro-2H-chromen-3-yl)methyl-idene]-N-phenyl-hydrazinecarbo-thio-amide.

The title compounds, C13H13N3O2S·0.5H2O, (I), and C17H14ClN3OS, (II), are hydrazinecarbo-thio-amide derivatives. Compound (I) crystallizes with two independent mol-ecules (A and B) and a water mol-ecule of crystallization in the asymmetric unit. The chromene moiety is essentially planar in mol-ecules A and B, with maximum deviations of 0.028 (3) and 0.016 (3) Å, respectively, for the carbonyl C atoms. In (II), the pyran ring of the chromene moiety adopts a screw-boat conformation and the phenyl ring is inclined by 61.18 (9)° to its mean plane. In the crystal of (I), bifurcated N-H⋯O and C-H⋯O hydrogen bonds link the two independent mol-ecules forming A-B dimers with two R 2 (1)(6) ring motifs, and R 2 (2)(10) and R 2 (2)(14) ring motifs. In addition to these, the water mol-ecule forms tetra-furcated hydrogen bonds which alternately generate R 4 (4)(12) and R 6 (6)(22) graph-set ring motifs. There are also π-π [inter-centroid distances = 3.5648 (14) and 3.6825 (15) Å] inter-actions present, leading to the formation of columns along the c-axis direction. In the crystal of (II), mol-ecules are linked by pairs of N-H⋯S hydrogen bonds, forming inversion dimers with an R 2 (2)(8) ring motif. The dimers are linked by C-H⋯π inter-actions, forming ribbons lying parallel to (210).

Crystal structure of 2,9-diphenyl-17λ(6)-thia-tetra-cyclo-[8.7.0.0(3,8).0(11,16)]hepta-deca-1(10),2,4,6,8,11(16),12,14-octa-ene-17,17-dione.

The title compound, C28H18O2S, is composed of a naphthalene ring system fused with a benzo-thio-phene ring and attached to two phenyl rings. The phenyl rings make dihedral angles of 70.92 (8) and 79.23 (8)° with the essentially planar naphthalene ring system (r.m.s. deviation = 0.031 Å). There is an intra-molecular C-H⋯π inter-action present. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds which generate C(7) zigzag chains running parallel to [10-1]. The chains are linked via further C-H⋯π inter-actions, forming a three-dimensional structure.

Crystal structure of (E)-2-[(4-chloro-2H-chromen-3-yl)methyl-idene]-N-cyclo-hexyl-hydrazinecarbo-thio-amide.

In the title compound, C17H20ClN3OS, the mean plane of the central thio-urea core makes dihedral angles of 26.56 (9) and 47.62 (12)° with the mean planes of the chromene moiety and the cyclo-hexyl ring, respectively. The cyclo-hexyl ring adopts a chair conformation. The N-H atoms of the thio-urea unit adopt an anti conformation. The chromene group is positioned trans, whereas the cyclo-hexyl ring lies in the cis position to the thione S atom, with respect to the thio-urea C-N bond. In the crystal, mol-ecules are linked by N-H⋯S hydrogen bonds, forming inversion dimers enclosing R (2) 2(8) ring motifs. The dimers are linked by C-H⋯Cl hydrogen bonds, enclosing R (6) 6(44) ring motifs, forming sheets lying parallel to (010).

Crystal structure of 3-methyl-2,6-bis-(4-methyl-1,3-thia-zol-5-yl)piperidin-4-one.

In the title compound, C14H17N3OS2, the central piperidinone ring adopts a chair conformation and the thia-zole rings are inclined to its mean plane by 80.16 (12) and 67.15 (12)°. The O atom and methyl group C atom deviate significantly from the mean plane of the central piperidinone ring, by 0.8138 (2) and 0.3175 (2) Å, respectively. The dihedral angle between the thia-zole rings is 51.88 (13)°. In the crystal, mol-ecules are linked via C-H⋯O hydrogen bonds, forming zigzag C(10) chains running parallel to [001].

Crystal structure of 4-(4-meth-oxy-phen-yl)-7,7-dimethyl-2-methyl-amino-3-nitro-7,8-di-hydro-4H-chromen-5(6H)-one.

In the title compound, C19H22N2O5, the six-membered carbocyclic ring of the chromene moiety adopts an envelope conformation with the dimethyl-substituted C atom as the flap. The pyran ring has a flat-boat conformation. The meth-oxy-phenyl ring is orthogonal to the mean plane of the chromene moiety, with a dihedral angle of 89.97 (8)°. The amine N atom deviates from the chromene mean plane by 0.1897 (16) Å. The methyl-amine and the nitro group are involved in an intra-molecular N-H⋯O hydrogen bond which generates an S(6) ring motif. They are slightly twisted out of the plane of the chromene moiety with torsion angles of C-N-C-O(pyran) = 2.2 (3)° and O(nitro)-N-C-C = -5.6 (2)°. In the crystal, there are only C-H⋯π inter-actions present, forming inversion-related dimers.

3,10,14,21-Tetra-kis(4-meth-oxy-phen-yl)penta-cyclo-[11.8.0.0(2,11).0(4,9).0(15,20)]henicosa-1(21),2,4(9),5,7,10,13,15(20),16,18-decaen-12-one chloro-form monosolvate.

The asymmetric unit of the title compound, C49H36O6·CHCl3, contains half an organic mol-ecule, the complete mol-ecule being generated by the operation of a crystallographic twofold rotation axis, and half a highly disordered chloro-form mol-ecule. The contribution to the diffraction pattern of the latter was removed using the program SQUEEZE in PLATON [Spek (2009 ▶). Acta Cryst. D65, 148-155]; the unit-cell characteristics take into account the presence of CHCl3. The dihedral angles between the planes of the naphthalene ring system and the meth-oxy-benzene rings are 71.05 (7) (syn to the central C=O group) and 57.27 (6)° (anti to the central C=O group). In the crystal, mol-ecules are linked by C-H⋯O inter-actions, generating C(12) chains running parallel to the b axis.

3-Bromo-methyl-4-meth-oxy-2-(2-nitro-phen-yl)-9-phenyl-sulfonyl-9H-carbazole.

In the title compound, C26H19BrN2O5S, the carbazole tricycle is essentially planar, with the largest deviation being 0.126 (3) Šfor the C atom connected to the nitro-phenyl group. The carbazole moiety is almost orthogonal to the benzene rings of the adjacent phenyl-sulfonyl and nitro-phenyl groups, making dihedral angles of 85.43 (15) and 88.62 (12)°, respectively. The mol-ecular conformation is stabilized by two C-H⋯O hydrogen bonds involving the sulfone group, which form similar six-membered rings. In the crystal, mol-ecules symmetrically related by a glide plane are linked in C(6) chains parallel to [001] by C-H⋯O hydrogen bonds formed with the participation of the nitro group. The chains are reinforced by additional C-H⋯π inter-actions.

Methyl (E)-3-(2-formyl-phen-oxy)acrylate.

In the title compound, C11H10O4, the methyl acrylate sub-stituent adopts an extended E conformation with all torsion angles close to 180°. The conformation of the keto group with respect to the olefinic double bond is typically S-trans. In the crystal, mol-ecules are linked via pairs of C-H⋯O hydrogen bonds, forming inversion dimers with an R 2 (2)(8) graph-set motif. The dimers are further linked via C-H⋯O hydrogen bonds, forming chains along [001], which enclose R 3 (2)(16) graph-set ring motifs. The keto group O atomaccepts two C-H⋯O interactions.

7,7-Dimethyl-2-methyl-amino-4-(4-methyl-phenyl)-3-nitro-7,8-di-hydro-4H-chromen-5(6H)-one.

In the title compound, C19H22N2O4, the six-membered cyclo-hexenone ring of the chromene unit adopts an envelope conformation, with the dimethyl-substituted C atom as the flap, while the pyran ring has a boat conformation. These two mean planes are inclined to one another by 6.65 (13)°·The benzene ring is normal to the 4H-chromene moiety mean plane, making a dihedral angle of 89.18 (5)°. The methyl-amine and nitro groups are slightly twisted from the chromene moiety mean plane, with torsion angles C-N-C-O = 1.70 (18) and O-N-C-C = 0.15 (18)°. The mol-ecular structure is characterized by an intra-molecular N-H⋯O hydrogen bond, which generates an S(6) ring motif. In the crystal, mol-ecules are linked via pairs of weak C-H⋯O hydrogen bonds, forming inversion dimers. These dimers are connected by further C-H⋯O hydrogen bonds, forming sheets lying parallel to (10-1).

4-(4-Bromo-phen-yl)-7,7-dimethyl-2-methyl-amino-3-nitro-7,8-di-hydro-4H-chromen-5(6H)-one including an unknown solvate.

In the title compound, C18H19BrN2O4, the chromene unit is not quite planar (r.m.s. deviation = 0.199 Å), with the methyl C atoms lying 0.027 (4) and 1.929 (4) Šfrom the mean plane of the chromene unit. The six-membered carbocyclic ring of the chromene moiety adopts an envelope conformation, with the dimethyl-substituted C atom as the flap. The methyl-amine and nitro groups are slightly twisted from the chromene moiety, with C-N-C-O and O-N-C-C torsion angles of 2.7 (4) and -0.4 (4)°, respectively. The dihedral angle between the mean plane of the chromene unit and the benzene ring is 85.61 (13)°. An intra-molecular N-H⋯O hydrogen bond generates an S(6) ring motif, which stabilizes the mol-ecular conformation. In the crystal, mol-ecules are linked via N-H⋯O hydrogen bonds, forming hexa-gonal rings lying parallel to the ab plane. A region of disordered electron density, most probably disordered ethanol solvent mol-ecules, occupying voids of ca 432 Å(3) for an electron count of 158, was treated using the SQUEEZE routine in PLATON [Spek (2009 ▶). Acta Cryst. D65, 148-155]. Their formula mass and unit-cell characteristics were not taken into account during refinement.

2-(4,5-Dimeth-oxy-2-nitro-phen-yl)-4-meth-oxy-9-phenyl-sulfonyl-9H-carbazole-3-carbaldehyde.

In the title compound, C28H22N2O8S, the carbazole ring system is roughly planar, with a maximum deviation of 0.084 (3) Šfor the C atom connected to the 4,5-dimeth-oxy-2-nitro-phenyl ring. The dihedral angle between the carbazole system and the dimeth-oxy-substituted nitro-phenyl ring is 57.05 (10)°. The aldehyde C atom deviates by 0.164 (5) Šfrom its attached carbazole ring system. The mol-ecular structure is stabilized by C-H⋯O inter-actions which generate two S(6) and one S(7) ring motif. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds, forming R 3 (3)(15) ring motifs, which are further crosslinked by R 3 (2)(19) ring motifs, resulting in (002) layers. The crystal packing also features C-H⋯π inter-actions.

Methyl 4-(4-bromo-anilino)-2',5-dioxo-5H-spiro-[furan-2,3'-indoline]-3-carboxyl-ate.

In the title compound, C19H13BrN2O5, the spiro furan ring is almost planar with a maximum deviation of 0.034 (2) Å. The indole unit and the furan ring are normal to each other, making a dihedral angle of 87.82 (8) °. The mol-ecular structure is stabilized by an intra-molecular N-H⋯O hydrogen bond, which generates an S(6) ring motif. In the crystal, mol-ecules are linked via pairs of N-H⋯O hydrogen bonds, forming inversion dimers enclosing R (2) 2(8) ring motifs.