The asymmetric unit of the title compound, C6H11N3O, consists of two independent mol­ecules in which the cyclo­pentane rings adopt envelope conformations with CH2 grouping as the flap and the semicarbazone groups are essentially planar, with maximums deviation of 0.0311 (12) and 0.0285 (12) Å. In the crystal, N—H⋯O, N—H⋯N and C—H⋯O hydrogen bonds link the mol­ecules to form sheets lying parallel to the ab plane.

The asymmetric unit of the title compound, C21H18O2S, consists of two crystallographically independent mol­ecules (A and B). The mol­ecules exist in a trans conformation with respect to the central C=C bond. The naphthalene ring system makes dihedral angles of 51.62 (12) (mol­ecule A) and 52.69 (12)° (mol­ecule B) with the benzene ring. In mol­ecule A, the prop-2-en-1-one group forms dihedral angles of 22.84 (15) and 29.02 (12)° with the adjacent naphthalene ring system and benzene ring, respectively, whereas the corresponding angles are 30.04 (12) and 23.33 (12)° in mol­ecule B. In the crystal, mol­ecules are linked by inter­molecular C—H⋯O hydrogen bonds into head-to-tail chains along the a axis. The crystal packing also features C—H⋯π inter­actions. The crystal studied was a pseudo-merohedral twin with twin law (100 0-10 00-1) and a refined component ratio of 0.6103 (16):0.3897 (16).

In the title mol­ecule, C19H24O6, the cyclo­hexa­none ring adopts a chair conformation. The dihedral angle between the phenyl ring and the best plane through the six atoms of the cyclo­hexa­none ring is 89.68 (7)°. In the crystal structure, mol­ecules are linked via pairs of inter­molecular O—H⋯O hydrogen bonds into centrosymmetric dimers and these dimers are connected by C—H⋯O inter­actions into columns down the a axis.

In the title nicotinonitrile derivative, C18H15N3OS, the central pyridyl ring makes dihedral angles of 25.22 (10) and 24.80 (16)° with the 4-amino­phenyl and thio­phene rings, respectively. The thio­phene ring is disordered over two orientations by rotation around the C(thio­phene)—C(pyridine) bond; the occupancies are 0.858 (2) and 0.142 (2). The eth­oxy group is slightly twisted from the attached pyridyl ring [C—O—C—C torsion angle = 171.13 (16)°]. In the crystal structure, mol­ecules are linked by N—H⋯N hydrogen bonds into chains along [010]. These chains are stacked along the a axis. C—H⋯π weak inter­actions involving the thio­phene ring are observed.

There are two mol­ecules in the asymmetric unit of the title compound, C23H21BrN2O4, which differ in the conformation of their ethoxy residues, i.e. almost co-planar with the pyridine ring in one mol­ecule [C—O—C—C = −174.0 (2)°] but almost perpendicular in the other [C—O—C—C = 92.8 (3)°]. The dihedral angles between the central pyridine ring and the 4-bromo­phenyl and 2,4,5-trimethoxy­phenyl rings are 11.05 (12) and 63.78 (12)°, respectively, in one mol­ecule; the corres­ponding angles in the other mol­ecule are 30.38 (13) and 65.38 (13)°, respectively. In the crystal structure, pairs of mol­ecules are arranged in a face-to-face sandwich structure which further stacks along the b axis. The crystal packing features C—H⋯π inter­actions and Br⋯O [3.5417 (17) Å], Br⋯C [3.748 (3) Å], C⋯N [3.376 (4) Å] and C⋯O [3.351 (3)–3.409 (3) Å] contacts. Finally, π⋯π inter­actions [centroid⋯centroid distances = 3.6346 (19) and 3.6882 (19) Å] are observed.

The mol­ecule of the title nicotinonitrile derivative, C22H19BrN2O2, is non-planar, the central pyridine ring making dihedral angles of 7.34 (14) and 43.56 (15)° with the 4-bromo­phenyl and 4-ethoxy­phenyl rings, respectively. The eth­oxy group of the 4-ethoxy­phenyl is slightly twisted from the attached benzene ring [C—O—C—C = 174.2 (3)°], whereas the eth­oxy group attached to the pyridine ring is in a (+)syn-clinal conformation [C—O—C—C = 83.0 (3)°]. A weak intra­molecular C—H⋯N inter­action generates an S(5) ring motif. In the crystal structure, the mol­ecules are linked by weak inter­molecular C—H⋯N inter­actions into screw chains along the b axis. These chains stacked along the a axis. π–π inter­actions with centroid–centroid distances of 3.8724 (16) and 3.8727 (16) Å are also observed.

In the asymmetric unit of the title nicotinonitrile derivative, C23H21BrN2O4, there are two non-planar independent mol­ecules. The central pyridine ring makes dihedral angles of 9.05 (7) and 77.06 (7)°, respectively, with the 4-bromo­phenyl and 2,4,6-trimethoxy­phenyl rings in one mol­ecule, whereas the corresponding values are 5.96 (7) and 82.37 (7)° in the other. All the three meth­oxy groups are essentially in the plane of the attached benzene ring [C—O—C—C angles = 2.99 (19), 4.8 (2) and −6.2 (2)° in one mol­ecule, and 2.69 (18), 176.73 (15) and 1.3 (2)° in the other]. The eth­oxy group is slightly twisted in one mol­ecule [C—C—O—C = 173.84 (12)°], whereas it is coplanar with the pyridine ring in the other [C—C—O—C = −177.23 (13)°]. Weak intra­molecular C—H⋯N inter­actions generate S(5) ring motifs. In the crystal structure, the mol­ecules are linked by weak inter­molecular C—H⋯N and C—H⋯O inter­actions into a supra­molecular three-dimensional network in such a way that the nicotinonitrile units of neighboring mol­ecules are stacked in an anti­parallel manner along the c axis. The crystal is further stabilized by C—H⋯π inter­actions.

In the title mol­ecule, C9H13N3O, the non-hydrogen atoms of the hydrazide group are essentially planar [maximum deviation = 0.028 (1) Å for one of the N atoms]. The mean plane of this group forms a dihedral angle of 83.34 (5)° with the plane of the benzene ring. In the crystal structure, mol­ecules are linked by inter­molecular N—H⋯O, N—H⋯N and weak C—H⋯N hydrogen bonds into a two-dimensional network parallel to the ab plane. Additional stabilization is provided by a weak C—H⋯π inter­action.

The mol­ecule of the title compound, C10H13N5OS, is approximately planar, the dihedral angle between the triazole and benzene rings being 4.53 (10)°. The amino group adopts a pyramidal configuration. In the crystal structure, mol­ecules are linked into two-dimensional networks parallel to (001) by inter­molecular N—H⋯S and N—H⋯N hydrogen bonds. In addition, an S⋯S short contact of 3.3435 (7) Å is observed.

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.

In the title compound, C9H11N3O, the benzene ring is disordered over two positions with refined occupancies of 0.922 (5) and 0.078 (5). The program PLATON [Spek (2009 ▶). Acta Cryst. D65, 148–155] recommends the solution in the space group C2/m with a = 7.3050 (3), b = 6.6745 (2), c = 18.3853 (6) Å and β = 96.986 (2)°. However, the large number of non-extinct reflections needed to be ignored if C2/m is chosen suggested that the space group is incorrect, even though the R values are lower than that for P21/c. The semicarbazone group is essentially planar, with a maximum deviation of 0.046 (1) Å for one of the N atoms. The mean plane of the semicarbazone group forms dihedral angles of 33.61 (8) and 39.1 (9)° with the benzene ring of the major and minor components, respectively. In the crystal structure, mol­ecules are linked by inter­molecular N—H⋯O hydrogen bonds into extended chains along the c axis. The crystal structure is further stabilized by weak inter­molucular C—H⋯π inter­actions.

In the title compound, C9H10FN3O, the semicarbazone group is nearly planar, with the maximum deviation of 0.044 (1) Å for one of the N atoms. The mean plane of semicarbazone group forms a dihedral angle of 30.94 (4)° with the benzene ring. The mol­ecules are linked into a supra­molecular chain by N—H⋯O hydrogen bonds formed along the c axis. The crystal structure is further stabilized by weak inter­molucular C—H⋯π inter­actions; the closest C⋯Cg contact is 3.6505 (11) Å.

In the title compound, C9H10ClN3O, the semicarbazone group is approximately planar, with an r.m.s. deviation from the mean plane of 0.054 (1) Å. The dihedral angle between the least-squares planes through the semicarbazone group and the benzene ring is 30.46 (5)°. In the solid state, mol­ecules are linked via inter­molecular N—H⋯O and N—H⋯N hydrogen bonds, generating R 2 2(9) ring motifs which, together with R 2 2(8) ring motifs formed by pairs of inter­molecular N—H⋯O hydrogen bonds, lead to the formation of a seldom-observed mol­ecular trimer. Furthermore, N—H⋯O hydrogen bonds form R 2 1(7) ring motifs with C—H⋯O hydrogen bonds, further consolidating the crystal structure. Mol­ecules are linked by these inter­molecular inter­actions, forming two-dimensional networks parallel to (100).

In the title compound, C9H10BrN3O, the hydrazone portion and aliphatic chain are essentially coplanar [maximum deviation 0.057 (15) Å] and the mean plane makes a dihedral angle of 70.9 (6)° with the benzene ring. The main feature of the crystal structure is the inter­molecular N—H⋯O hydrogen bond, which links mol­ecules into zigzag chains along the a axis. These chains are further stacked along the b axis. The crystal structure features non-classical inter­molecular C—H⋯O inter­actions. The crystal studied was a nonmerohedral twin, with a twin ratio of 0.505 (1):0.495 (1).

The title compound, C14H18N2O3, crystallizes with two independent mol­ecules in the asymmetric unit, having closely comparable geometries. Both mol­ecules are essentially planar [maximum deviations from the mean plane of 0.069 (1) and 0.068 (1) Å for the two mol­ecules] and contain an intra­molecular N—H⋯O hydrogen bond which generates a ring with graph-set motif S(6). In the crystal, the mol­ecules are linked into chains along the c axis by inter­molecular C—H⋯O hydrogen bonds, and inter­molecular C—H⋯π inter­actions are also present.

The mol­ecule of the title oxobutanoate derivative, C12H13ClN2O3, adopts a keto–hydrazo tautomeric form and is roughly planar, the angle between the benzene ring and the mean plane through the hydrazone and aliphatic chain being 1.49 (6)°. This planarity is further aided by the formation of an intra­molecular N—H⋯O hydrogen bond which generates an S(6) ring motif. The aromatic ring and aliphatic chain have a trans configuration with respect to the N—N bond. In the crystal packing, centrosymmetric R 2 2(16) dimers are formed through pairs of weak C—H⋯O(3-oxo) inter­actions. These dimers are linked together through weak C—H⋯O(carboxyl­ate C=O) inter­actions into ribbons along the b-axis direction. These ribbons are stacked along the a-axis direction. The crystal also exhibits Cl⋯Cl [3.4988 (6) Å] and C⋯O [3.167 (2)–3.335 (2) Å] short contacts.

The mol­ecule of the title oxobutanoate derivative, C12H13ClN2O3, is nearly planar; the inter­planar angle between the benzene ring and the mean plane through the hydrazono-3-oxobutanoate unit is 2.69 (3)°. An intra­molecular N—H⋯O hydrogen bond generates an S(6) ring motif. In the crystal packing, C—H⋯O(3-oxo) inter­actions link mol­ecules into dimers. The dimers thus formed are linked through C—H⋯O(carboxyl­ate C=O) inter­actions, leading to the formation of ribbons along the [01] direction, which are stabilized via Cl⋯Cl [3.2916 (3) Å] contacts. The ribbons are stacked via C⋯O contacts [3.2367 (12)–3.3948 (12) Å].