Crystal structures of ethyl (2S*,2′R*)-1′-methyl-2′′,3-dioxo-2,3-di­hydro­dispiro­[1-benzo­thio­phene-2,3′-pyrrolidine-2′,3′′-indoline]-4′-carboxyl­ate and ethyl (2S*,2′R*)-5′′-chloro-1′-methyl-2′′,3-dioxo-2,3-di­hydro­dispiro­[1-benzo­thio­phene-2,3′-pyrrolidine-2′,3′′-indoline]-4′-carboxyl­ate

The title compounds, (I) and (II), are di­spiro-indole-pyrrolidine-benzo­thio­phene derivatives, with (II) having a chlorine substituent on the oxo­indole unit. As a result, the conformation of the two mol­ecules differs in the angle of inclination of the indole moiety with respect to the benzo­thio­phene ring system, with a dihedral angle of 71.59 (5) in (I) and 82.27 (7)° in (II).

Crystal structures of methyl 3-phenyl-4,5-di­hydro-1H,3H-benzo[4,5]imidazo[2,1-c][1,4]oxazepine-4-carboxyl­ate and methyl 1-methyl-3-phenyl-4,5-di­hydro-1H,3H-benzo[4,5]imidazo[2,1-c][1,4]oxazepine-4-carboxyl­ate

In two benzo[4,5]imidazo[2,1-c][1,4]oxazepine-4-carboxyl­ates, the seven-membered oxazepane rings both have a twist-chair conformation. The dihedral angle between the phenyl ring and the benzimidazole ring system is significantly smaller in one of the compounds, viz. 73.42 (10) compared to 83.07 (17)°.

Methyl 1-ethyl-3′-[hy­droxy(naphthalen-1-yl)meth­yl]-1′-methyl-2-oxo­spiro­[indo­line-3,2′-pyrrolidine]-3′-carboxyl­ate

In the title compound, C₂₇H₂₈N₂O₄, the pyrrolidine ring adopts a twist conformation. The plane of the indole ring is almost perpendicular to that of the pyrrolidine ring, making a dihedral angle of 88.50 (6)°. The planes of the naphthyl ring system and the pyrrolidine ring are tilted by an angle of 55.86 (5)°. The mol­ecular conformation is stabilized by intra­molecular O—H...O and O—H...N hydrogen bonds.

(E)-N′-(3,4-Di­meth­oxy­benzyl­idene)nicotinohydrazide monohydrate

In the title hydrated compound, C₁₅H₁₅N₃O₃·H₂O, the nicotinohydrazide mol­ecule adopts a trans conformation with respect to the C=N double bond. The dihedral angle between the benzene and pyridine rings is 5.10 (14)°. In the crystal, the solvent water mol­ecule acts as an acceptor, forming an N—H...O hydrogen bond supported by two C—H...O contacts. It also acts as a donor, forming bifurcated O—H...(O,O) and O—H...N hydrogen bonds that combine with the former contacts to form zigzag chains of mol­ecules along the c-axis direction. An additional O—H...O donor contact completes a set of six hydrogen bonds to and from the water mol­ecule and connects it to a third nicotinohydrazide mol­ecule. This latter contact combines with weaker C—H...O hydrogen bonds supported by a C—H...π contact to stack mol­ecules along b in a three-dimensional network.

Crystal structure of 3-({[(thio­phen-2-yl)methyl­idene]hydrazin­yl}carbon­yl)pyridinium chloride dihydrate

In the title compound, C₁₁H₁₀N₃OS⁺·Cl⁻·2H₂O, the organic cation exhibits a dihedral angle of 21.26 (8)° between the mean planes of the pyridine and thio­phene rings, and dihedral angles of 15.11 (9) and 6.49 (9)° between the mean planes of the hydrazide moiety and the pyridine and thio­phene rings, respectively. In the crystal, the organic cation, the chloride counter-anion and the two water mol­ecules of crystallization are linked through an intricate hydrogen-bonding network consisting of O—H...O, O—H...N, N—H...Cl, C—H...Cl, C—H...O, N—H...O, O—H...Cl and C—H...S inter­actions that consolidate a three-dimensional network.

Crystal structure of ethyl 6-(chloro­meth­yl)-4-(4-chloro­phen­yl)-2-oxo-1,2,3,4-tetra­hydro­pyrimidine-5-carboxyl­ate

In the title compound, C₁₄H₁₄Cl₂N₂O₃, the chloro­phenyl ring makes a dihedral angle of 87.08 (9)° with the tetra­hydro­pyrimidine ring. There is a short intra­molecular C—H...O contact present. In the crystal, mol­ecules are linked via pairs of N—H...O hydrogen bonds, forming inversion dimers with an R²₂(8) ring motif. The dimers are linked via a second pair of N—H...O hydrogen bonds, this time enclosing an R⁴₄(20) ring motif, forming ribbons along [100]. The ribbons are linked via C—H...O hydrogen bonds, forming sheets lying parallel to (001). The terminal ethyl group is disordered over two positions with an occupancy ratio of 0.654 (17):0.346 (17).