Related Articles

In the title compound, C15H13N3O4, the pyridine and benzene rings are nearly perpendicular [dihedral angle = 84.24 (5)°]. In the crystal structure, classical O—H⋯N hydrogen bonding between the OH group of the carboxyl unit and a neighbouring pyridine ring N atom and N—H⋯O hydrogen bonding between the imine NH group and a neighbouring O atom of an acyl unit, together with complementary non-classical C—H⋯O hydrogen bonds between carboxyl O atoms and neighbouring CH groups, link the mol­ecules into a three-dimensional system.

In the title compound, C13H12ClN3·H2O, the organic mol­ecule is almost planar, with a dihedral angle of 3.22 (10)° between the benzene and pyridine rings. The crystal structure is stabilized by O—H⋯N and C—H⋯O hydrogen bonding and π–π stacking inter­actions [centroid–centroid distances = 3.630 (1) and 3.701 (1) Å].

In the title compound, C13H10N4O5·0.5C2H5OH, the two benzene rings form a dihedral angle of 4.29 (9)°. The ethanol solvent mol­ecule was treated as disordered between two orientations related by symmetry (center of inversion), with occupancies fixed at 0.5. The crystal packing, stabilized by inter­molecular O—H⋯O and N—H⋯O hydrogen bonds and π–π inter­actions [indicated by the short distance of 3.7299 (7) Å between the centroids of benzene rings from neighbouring mol­ecules], exhibits short inter­molecular O⋯O contacts of 2.8226 (3) Å.

In the title compound, C16H13ClFN3O2S, the dihedral angle between the benzene rings is 4.47 (3)°. The conformation of the thia­zine ring is a half-chair and the Cl atom is in an axial orientation. In the crystal, mol­ecules are linked by C—H⋯F inter­actions, generating C(12) chains propagating in [011]. Aromatic π–π stacking inter­actions [centroid–centroid separations = 3.753 (2) and 3.758 (2) Å] also occur.

In the title compound, C17H16BrN3O2S, the dihedral angle between the aromatic rings is 1.24 (15)° and the C=N—N=C torsion angle is 167.7 (3)°. The conformation of the thia­zine ring is an envelope, with the S atom displaced by 0.805 (3) Å from the mean plane of the other five atoms (r.m.s. deviation = 0.027 Å). In the crystal, C—H⋯O inter­actions link the mol­ecules into C(10) [010] chains. A weak C—H⋯π inter­action is also observed.

In the title compound, C17H15N3O4, the mol­ecule is in the keto–hydrazone form. Intra­molecular N—H⋯O hydrogen bonds ensure that the mol­ecule is nearly planar (r.m.s. deviation of non-H atoms is 0.098 Å), with the two benzene rings forming a dihedral angle of 10.04 (2)°. In the crystal, inversion dimers are formed via pairs of O—H⋯O hydrogen bonds involving the –CO2H groups.

The complete mol­ecule of the title compound, [Cd(C6H12NOS2)2(C12H10N4)2], is generated by crystallographic inversion symmetry. The distorted octa­hedral trans-N2S4 donor set for the Cd2+ ion is defined by two symmetrically S,S′-chelating dithio­carbamate anions and two pyridine N atoms derived from two monodentate 4-pyridine­aldazine (or 4-{[(pyridin-4-yl­methyl­idene)hydrazinyl­idene}meth­yl]pyridine) mol­ecules [dihedral angle between the aromatic rings = 17.33 (8)°]. In the crystal, mol­ecules are connected into a supra­molecular chain via O—H⋯N hydrogen bonds involving the 4-pyridine­aldazine N atoms not involved in coordination to cadmium. Weak C—H⋯O and C—H⋯N links consolidate the packing.

The 30 non-H atoms in title dihydrazine compound, C20H16N6O4·2H2O, are close to coplanar, the r.m.s. deviation for these atoms being 0.096 Å. The conformation about each of the C=N bonds is E, and the mol­ecule has non-crystallographic 2/m symmetry. The presence of O—H⋯O and N—H⋯O hydrogen bonding leads to a three-dimensional network in the crystal structure. A highly disordered solvent mol­ecule is present within a mol­ecular cavity defined by the organic and water mol­ecules. Its contribution to the electron density was removed from the observed data in the final cycles of refinement and the formula, molecular weight and density are given without taking into account the contribution of the solvent molecule.

In the title compound, C24H18ClN3O2S, the dihedral angle between the benzene ring and the anthracene ring system is 41.10 (8)°. The thia­zine ring has a half-chair conformation and the Cl atom is in an axial orientation. In the crystal, mol­ecules are linked by C—H⋯O inter­actions, generating C(8) chains along [100]. A C—H⋯N short contact occurs in the mol­ecule, generating an S(6) ring.

The asymmetric unit of the title compound, C12H12F2N2O3, contains two mol­ecules, both of which exist in an E conformation with respect to their C=N bonds [1.321 (6) and 1.310 (6) Å]. The mol­ecular conformations are supported by intra­molecular N—H⋯O hydrogen bonds, which generate S(6) rings. In the crystal, mol­ecules are linked by C—H⋯O and C—H⋯F hydrogen bonds into layers lying parallel to (001). The crystal studied was an inversion twin with a 0.58 (1):0.42 (1) domain ratio.

The mol­ecule of the title Schiff base compound, C15H14N2O5, was obtained from a condensation reaction of 4-acet­oxy-3-meth­oxy­benzaldehyde and 2-furyl­carbonyl­hydrazide. In the mol­ecule, the furyl ring makes a dihedral angle of 14.63 (10)° with the benzene ring. In the crystal, inter­molecular N—H⋯O hydrogen bonds link the mol­ecules into chains along the b axis. Futhermore, weak C—H⋯O inter­actions connect the chains, forming corrugated layers parallel to (001). The dihedral angle between the rings is 14.63 (10)°.

The mol­ecule of the title Schiff base compound, C16H15N3O5, obtained from a condensation reaction of 4-acet­oxy-3-meth­oxy­benzaldehyde and 4-nitro­phenyl­hydrazine, adopts an E geometry with respect to the C=N double bond. The mol­ecule is roughly planar, with the two benzene rings twisted slightly with respect to each other by a dihedral angle of 6.90 (9)°. In the crystal, inter­molecular N—H⋯O hydrogen bonds link centrosymmetrically related pairs of mol­ecules, forming dimers of R 2 2(22) graph-set motif. The dimers are further connected through slipped π–π inter­actions between symmetry-related benzene rings [centroid–centroid distance of 3.646 (1) Å, offset angle of 15.4°].

The title compound, C19H15ClN6O3S, exists in trans and cis configurations with respect to the acyclic C=N bonds. The 3,6-dihydro-2H-1,3,4-thia­diazine ring adopts a half-boat conformation. The sydnone ring is approximately planar [maximum deviation = 0.013 (1) Å] and forms dihedral angles of 34.76 (4) and 48.67 (4)° with the benzene rings. An intra­molecular C—H⋯O hydrogen bond stabilizes the mol­ecular structure and forms an S(6) ring motif. In the crystal packing, inter­molecular N—H⋯N hydrogen bonds link centrosymmetrically related mol­ecules into dimers, generating R 2 2(8) ring motifs. The dimers are then linked into a three-dimensional network by inter­molecular C—H⋯O and C—H⋯Cl hydrogen bonds, and by C—H⋯π inter­actions. Further stabilization is provided by π–π inter­actions involving the sydnone rings, with centroid–centroid separations of 3.4198 (5) Å.

The title compound, C18H13ClN6O2S, exists in trans and cis configurations with respect to the acyclic C=N bonds [C=N = 1.2837 (15) and 1.3000 (14) Å, respectively]. The 3,6-dihydro-2H-1,3,4-thia­diazine ring adopts a half-boat conformation. The sydnone ring is approximately planar [maximum deviation = 0.002 (1) Å] and forms dihedral angles of 50.45 (7) and 61.21 (6)° with the aromatic rings. In the crystal, inter­molecular N—H⋯N, C—H⋯Cl and C—H⋯S hydrogen bonds link the mol­ecules into layers parallel to ab plane. The crystal packing is stabilized by C—H⋯π inter­actions and further consolidated by π–π inter­actions involving the phenyl rings [centroid–centroid distance = 3.6306 (7) Å].

In the title compound, C16H13Cl2N3O2S, the dihedral angle between the aromatic rings is 6.62 (2)° and the C=N—N=C torsion angle is 176.2 (4)°. The thia­zine ring shows an envelope conformation, with the S atom displaced by 0.633 (6) Å from the mean plane of the other five atoms (r.m.s. deviation = 0.037 Å). The Cl atom is an an axial conformation and is displaced by 2.015 (6) Å from the thia­zine ring plane. In the crystal, mol­ecules are linked by C—H⋯O inter­actions, generating a three-dimensional network. Very weak aromatic π–π stacking inter­actions [centroid–centroid separations = 3.928 (2) Å] are also observed.

The chiral title compound, C21H20N4O2, crystallizes as a racemic mixture. In the crystal, mol­ecules form centrosymmetric π-overlapping dimers [inter­planar distance = 3.338 (6) Å], which are further connected along the a axis forming centrosymmetric dimers via O—H⋯N hydrogen bonds. C—H⋯O inter­actions are also observed. The indolo[2,1-b]quinazoline group is somewhat bent, with a small dihedral angle of 6.3 (4)° between the plane of the quinazoline system and the plane of the benzene ring of the indole moiety. The C=N—N=C atoms of the azine group is oriented almost perpendicular [84.1 (2)°] to the mean plane of the quinazoline system.

In the title compound, C19H21N3O2S, the dihedral angle between the aromatic rings is 6.7 (2)° and the C=N—N=C torsion angle is 178.0 (2)°. The conformation of the thia­zine ring is an envelope, with the S atom displaced by 0.802 (2) Å from the mean plane of the other five atoms (r.m.s. deviation = 0.022 Å). In the crystal, mol­ecules are linked by C—H⋯O inter­actions, generating C(5) chains propagating in [010]. A weak C—H⋯π inter­action is also observed.

In the title compound, C23H18N2O3, the inter­planar angle between the benzoyl units is 80.51 (6)° while the dihedral angles between the hydrazinyl­idene and benzoyl groups are 43.43 (6) and 54.16 (6)°. In the crystal, a strong resonance-assisted intra­molecular N—H⋯O hydrogen bond is observed. The mol­ecules form an inversion dimer via a pair of weak C—H⋯O hydrogen bonds and a π–π inter­action [centroid–centroid distance of 3.5719 (10) Å]. These dimers are linked via weak C—H⋯O contacts, forming chains along the b axis.

The title compound, C13H16N2O4, is approximately planar (r.m.s. deviation = 0.065 Å for the 19 non-H atoms). An intra­molecular N—H⋯O hydrogen bond generates an S(6) ring motif and the mol­ecule adopts an E conformation with respect to the central C=N double bond. In the crystal, pairs of inter­molecular C—H⋯O hydrogen bonds link adjacent mol­ecules into inversion dimers. The crystal structure also features weak C—H⋯π inter­actions.

In the title compound, C16H14ClN3O3S, the thia­zine ring adopts a sofa (half-chair) conformation, with an r.m.s. deviation from the mean plane of 0.23 Å. The S atom and S-bonded C atom exhibit the maximum deviations from the thia­zine mean plane [−0.3976 (12) and 0.3179 (14) Å, respectively]. The conformations around the double bonds in the R 2C=N—N=CHR unit are Z and E. An intra­molecular O—H⋯N hydrogen bond with the hy­droxy group as donor generates an S(6) ring motif. In the crystal, pairs of weak C—H⋯O inter­actions connect the mol­ecules, forming inversion dimers.

In the title compound, C13H16N2O4, an intra­molecular N—H⋯O hydrogen bond generates an S(6) ring. The mol­ecule adopts an E configuration with respect to the central C=N double bond. In the crystal, symmetry-related mol­ecules are connected into chains along [010] via weak C—H⋯N hydrogen bonds. The crystal structure is further stabilized by weak C—H⋯π inter­actions.

In the title Schiff base mol­ecule, C13H11ClN2O, the non-H atoms are approximately coplanar (r.m.s. deviation = 0.115 Å) and the two benzene rings are twisted by 9.36 (3)° with respect to each other. The hy­droxy group is hydrogen bonded to the azomethine N atom. In the crystal, an N—H⋯π inter­action is observed between the imino group and the hy­droxy­benzene ring of an adjacent mol­ecule.

In the title compound, C11H9F2N5OS, the pyrazole ring forms a dihedral angle of 16.42 (6)° with the benzene ring. Intra­molecular N—H⋯O hydrogen bonds generate two S(6) ring motifs. In the crystal, an R 2 2(8) ring motif is formed by a pair of inter­molecular N—H⋯S hydrogen bonds. Inter­molecular C—H⋯F hydrogen bonds further link the mol­ecules into a three-dimensional network.

In the title compound, C11H10BrN5OS, the approximately planar pyrazole ring [maximum deviation = 0.014 (2) Å] forms a dihedral angle of 5.49 (13)° with the benzene ring. An intra­molecular N—H⋯O hydrogen bond generates an S(6) ring motif. In the crystal, mol­ecules are linked through inter­molecular N—H⋯S and N—H⋯O hydrogen bonds, forming a two-dimensional network parallel to (100). A short Br⋯Br contact of 3.5114 (6) Å is also observed.

In the title mol­ecule, C9H10BrN3O2S, the thia­zine ring has an envelope conformation with the S atom at the flap. The geometry around the S atom is distorted tetra­hedral. In the crystal, inversion dimers linked by pairs of N—H⋯N hydrogen bonds occur, generating R 2 2(6) ring motifs. N—H⋯O hydrogen bonds and C—H⋯O inter­actions connect the dimers, forming a three-dimentional network structure.