Rajeswari Gangadharan

Crystal structures of two hydrazinecarbo­thio­amide derivatives: (E)-N-ethyl-2-[(4-oxo-4H-chromen-3-yl)methyl­idene]hydrazinecarbo­thio­amide hemi­hydrate and (E)-2-[(4-chloro-2H-chromen-3-yl)methyl­idene]-N-phenyl­hydrazinecarbo­thio­amide

The title compounds, (I) and (II), are hydrazinecarbothioamide derivatives. In the crystal of (I), two independent molecules are linked by bifurcated N—H⋯O and C—H⋯O hydrogen bonds, forming two (6) ring motifs, and (10) and (14) ring motifs. In the crystal of (II), molecules are linked by pairs of N—H⋯S hydrogen bonds, forming inversion dimers with an (8) ring motif.

Methyl 4-(4-bromo­anilino)-2′,5-dioxo-5H-spiro­[furan-2,3′-indoline]-3-carboxyl­ate

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 molecular structure is stabilized by an intramolecular N—H⋯O hydrogen bond, which generates an S(6) ring motif. In the crystal, molecules are linked via pairs of N—H⋯O hydrogen bonds, forming inversion dimers enclosing R 2 2(8) ring motifs.

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 thiourea core makes dihedral angles of 26.56 (9) and 47.62 (12)° with the mean planes of the chromene moiety and the cyclohexyl ring, respectively. The cyclohexyl ring adopts a chair conformation. The N–H atoms of the thiourea unit adopt an anti conformation. The chromene group is positioned trans, whereas the cyclohexyl ring lies in the cis position to the thione S atom, with respect to the thiourea C—N bond. In the crystal, molecules 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).

Methyl 4-anilino-2',5-dioxo-1',2'-di-hydro-5H-spiro-[furan-2,3'-indole]-3-carboxyl-ate.

In the title compound, C19H14N2O5, the spiro junction links an oxindole moeity and a furan ring, which subtend a dihedral angle of 83.49 (6)°. The molecular structure features an N—H⋯O hydrogen bond, which generates an S(6) ring motif. The crystal packing is governed by two N—H⋯O interactions, one of which generates a centrosymmetric R 2 2(14) dimer. The other N—H⋯O interaction along with a C—H⋯O hydrogen bond contributes to the formation of a C 2 2[R 2 2(9)] dimeric chain running along the b-axis direction.

1-Methyl-3-(naphthalen-1-yl)-3,3a,4,9b-tetra-hydro-1H-chromeno[4,3-c]isoxazole-3a-carbonitrile.

In the title compound, C22H18N2O2, the pyran ring of the chromene unit is fused with an isoxazole ring, which adopts an N-envelope conformation with the N atom lying 1.3291 (14) Å from the mean plane of the remaining ring atoms [maximum deviation = 0.341 (2) Å]. The dihedral angle between the isoxazole and chromene units is 43.74 (8)° and that between the iosxazole ring and the naphthalene ring system is 58.82 (8)°. In the crystal, the molecules are linked by weak C—H⋯π interactions.

(Z)-Methyl 3-(2,4-dichloro-phen-yl)-2-[(2-formyl-phen-oxy)meth-yl]acrylate.

In the title compound, C18H14Cl2O4, the mean planes of the methyl acrylate unit and the phenyl ring of the benzaldehyde are approximately orthogonal to each other, making a dihedral angle of 83.31 (6)°. The O atom of the aldehyde group is displaced significantly from the phenyl ring plane by 0.226 (2) Å. The methyl acrylate group adopts an E conformation. In the crystal, inversion dimers linked by pairs of C—H⋯O hydrogen bonds generate R 2 2(24) loops.

Crystal structures of three carbazole derivatives: 12-ethyl-7-phenyl­sulfonyl-7H-benzofuro[2,3-b]carbazole, (1), 2-(4,5-dimeth­oxy-2-nitro­phen­yl)-4-hy­droxy-9-phenyl­sulfonyl-9H-carbazole-3-carbaldehyde, (2), and 12-phenyl-7-phenyl­sulfonyl-7H-benzofuro[2,3-b]carbazole, (3)

The title compounds are carbazole derivatives. In all three compounds, the carbazole skeleton is essentially planar. In two of the compounds, a benzofuran moiety is fused with a carbazole unit. Intermolecular C—H⋯O hydrogen bonds give rise to (12) inversion dimers in one compound, and to (40) ring motifs and (24) inversion dimers in a second compound. In the crystal of the third compound, C—H⋯O hydrogen bonds link the molecules to form chains running parallel to the a axis.

Crystal structure of 3-[(E)-(2-hy­droxy-3-meth­oxy­benzyl­idene)amino]-1-methyl-1-phenyl­thio­urea

The asymmetric unit comprises two independent molecules. In the crystal, the two independent molecules are linked by bifurcated N—H⋯O hydrogen bonds, forming a supramolecular chain with a (14)[(5)] motif.

(Z)-Methyl 2-[(2-eth­oxy-6-formyl­phen­oxy)meth­yl]-3-(4-ethyl­phen­yl)acrylate

The title compound, C22H24O5, consists of two substituted benzene rings linked by an ethyl acrylate group. The dihedral angle between the two benzene rings is 58.39 (7)°. The crystal packing is governed by two C—H⋯O interactions, one of which forms centrosymmetric dimers with a graph-set descriptor of R 2 2(18).

3'-Hy-droxy-methyl-1'-methyl-3'-nitro-4'-(o-tol-yl)spiro-[indoline-3,2'-pyrrolidin]-2-one.

The title compound, C20H21N3O4, crystallizes with two molecules in the asymmetric unit. In both molecules, the pyrrolidine ring adopts an envelope conformation. The crystal structure is stabilized by intermolecular C—H⋯O, N—H⋯O and O—H⋯O hydrogen bonds.