In the title compound, C8H8Br2O2, all non-H atoms lie essentially in a common plane (r.m.s deviation of all fitted non-H atoms = 0.0330 Å). In the crystal, weak C—H⋯O hydrogen bonds connect the molecules, forming chains which extend along the b-axis direction.
In the title compound, C19H16F3NO6, a quinoline derivative featuring an annealated furan substituent, the mean planes of the carboxy substituents are at an angle of 74.3 (2)°. In the crystal, C—H⋯O contacts result in undulating chains along . C—H⋯F contacts also occur. The shortest centroid–centroid distance between rings is 3.3376 (7) Å, involving two furan rings of neighbouring molecules.
In the title compound, C21H23N3O4S·H2O, the methylsulfanyl group is disordered over two sets of sites with site-occupancy factors of 0.631 (11) and 0.369 (11). The dihydropyridine ring adopts an E
4 conformation. In the crystal, classical O—H⋯N, O—H⋯O and N—H⋯O hydrogen bonds, as well as C—H⋯O and C—H⋯S contacts, connect the molecules into a three-dimensional network.
In the title compound, C22H24ClN3O4, intramolecular C—H⋯O and C—H⋯N hydrogen bonds form S(9) and S(7) ring motifs, respectively. The 1,4-dihydropyridine ring adopts a flattened boat conformation. The benzene ring makes a dihedral angle of 33.36 (6)° with the pyrazole ring. In the crystal, pairs of N—H⋯N hydrogen bonds link the molecules into inversion dimers. The dimers are stacked in column along the a axis through N—H⋯O and C—H⋯N hydrogen bonds. The crystal packing also features C—H⋯π interactions involving the pyrazole ring.
In the title compound, C17H15ClO5, the benzene rings forms a dihedral angle of 74.45 (10)°. In the crystal, molecules are linked into C(13) chains along  via C—H⋯O hydrogen bonds. The crystal packing also features short Cl⋯Cl contacts of 3.1253 (10) Å.
In the title compound, C14H11Cl2NO, the benzene rings form a dihedral angle of 3.14 (6)°. Overall, the molecule is close to being planar (r.m.s. deviation for all the non-H atoms = 0.054 Å). No significant directional intermolecular interactions are observed in the crystal structure.
In the title compound, C28H29N3O4·C2H6O, the benzene ring makes dihedral angles of 33.72 (13) and 32.86 (13)°, respectively, with the adjacent pyrazole and phenyl rings. In the crystal, the components are connected via intermolecular N—H⋯O, N—H⋯N, O—H⋯O and C—H⋯O hydrogen bonds, forming a layer parallel to the bc plane.
In the title compound, C23H27N3O5, the pyrazole ring is inclined at dihedral angles of 38.16 (6) and 80.80 (6)°, respectively, to the least-squares planes of the benzene and dihydropyridine rings. In the crystal, adjacent molecules are linked via a pair of N—H⋯N hydrogen bonds, forming an inversion dimer. The dimers are stacked in a column along the a axis through N—H⋯O hydrogen bonds. Intra- and intermolecular C—H⋯N and C—H⋯O hydrogen bonds are also observed.
In the title compound, C23H29Cl2NO, the fluorene ring is essentially planar, with a maximum deviation from the mean plane of 0.041 (1) Å. The amine group adopts a pyramidal configuration, the sum of the bond angles being 336.2 (3)°. In the crystal, the molecules are linked into dimers by intermolecular O—H⋯N and C—H⋯O hydrogen bonds. Weak C—H⋯π and π–π [centroid–centroid distance = 3.7544 (7) Å] interactions are also observed.
In the title compound, C13H12N4OS, the dihedral angle between the triazole and naphthalene ring systems is 67.42 (5)°. In the crystal, adjacent molecules are linked via two pairs of intermolecular N—H⋯S interactions, forming R
2(8) and R
2(10) ring motifs. Weak C—H⋯S interactions generate infinite chains along  and the structure is further consolidated by C–H⋯π bonds and aromatic π⋯π stacking interactions [distance between the centroids of the triazole rings = 3.2479 (7) Å].
In the title compound, C9H9Cl2N3O, the semicarbazone group is approximately planar, with an r.m.s deviation from the mean plane of 0.011 (2) Å. The dihedral angle between the least-squares planes through the semicarbazone group and the benzene ring is 38.76 (9)°. The crystal structure is further stabilized by N—H⋯O and C—H⋯O hydrogen bonding.
In the title triazole compound, C10H12N4OS, the triazole ring is essentially planar [maximum deviation = 0.009 (1) Å] and forms a dihedral angle of 5.78 (4)° with the benzene ring. In the crystal structure, molecules are linked into dimers by centrosymmetric N—H⋯S interactions. These dimers are linked into two-molecule-wide tapes by N—H⋯N and S⋯S [3.2634 (3) Å] interactions. In addition, they are further interconnected by weak N—H⋯S interactions into sheets parallel to the ab plane. The crystal structure is further stabilized by weak intermolecular C—H⋯π interactions.
The asymmetric unit of the title compound, C10H12N4OS, contains two independent molecules, A and B, which differ significantly in the relative orientations of the benzene and triazole rings. The dihedral angle between the above two rings is 6.94 (5)° in molecule A and 77.60 (5)° in molecule B. In the crystal, molecules are linked into a three-dimensional network by N—H⋯S, N—H⋯O, N—H⋯N and C—H⋯S hydrogen bonds and π–π interactions between the benzene and triazole rings [centroid–centroid distance = 3.5311 (6) Å] are also present.
The title molecule, C7H7Cl2N3OS, is approximately planar [maximum deviation = 0.062 (1) Å]. Short intermolecular distances between the centroids of the five-membered rings [3.5340 (8) Å] indicate the existence of π–π interactions. An interesting feature of the crystal structure is the presence of short intramolecular Cl⋯N interactions [3.0015 (11) Å]. Molecules are linked via pairs of intermolecular N—H⋯O hydrogen bonds, generating R
2(8) ring motifs. Furthermore, N—H⋯O hydrogen bonds form R
1(7) ring motifs with C—H⋯O contacts, further consolidating the crystal structure. In the crystal, molecules are linked by these intermolecular interactions, forming chains along .
The title compound, C18H21N3O3, is a potential bidentate Schiff base ligand. The whole molecule is disordered with a refined site-occupancy ratio of 0.567 (4):0.433 (4) and not just one ethyl group as reported previously [Sarojini et al. (2007 ▶). Acta Cryst. E63, o4782–o4782]. Using the whole molecule disorder, R values are much smaller than those published. An intramolecular O—H⋯N hydrogen bond generates a six-membered ring, producing an S(6) ring motif. The dihedral angle between the mean plane of the two benzene rings (major component) is 9.0 (5)°. The crystal structure shows short C⋯C [3.189 (15)–3.298 (12) Å] and C⋯O [2.983 (5)–3.149 (13) Å] contacts. Intermolecular C—H⋯O interactions link neighbouring molecules into dimers with R
2(18) motifs. In the crystal structure, these dimers are linked together by intermolecular C—H⋯O interactions into one-dimensional extended chains along the b axis. The crystal structure is further stabilized by intermolecular π–π stacking interactions [centroid–centroid distances = 3.458 (8)–3.691 (6) Å].