The title molecule, C13H8N4, is is essentially planar [r.m.s. deviation for all non-H atoms = 0.025 (3) Å]. In the crystal, molecules are connected through one weak bifurcated N—H⋯(N,N) hydrogen bond and three π–π stacking interactions between pyridine and imidazole rings [centroid–centroid distance = 3.631 (8) Å] and between pyridine and benzene rings [centroid–centroid distances = 3.675 (5) and 3.666 (2) Å].
The organic cation of the title salt, C17H12N4O2+·2Cl−·H2O, is nearly planar, the dihedral angle between two pyridine rings being 2.53 (16)° and that between the pyridinum and furan rings being 4.17 (19)°. Molecules are linked via N—H⋯O, N—H⋯Cl and O—H⋯Cl hydrogen bonds, forming a three-dimensional framework and π–π stacking interactions help to stabilize the crystal structure [the imidazole–pyridine and imidazole–benzene centroid–centroid distances are 3.501 (3) and 3.674 (3) Å; respectively].
In the title compound, C20H18N4O2, the imidazopyridine fused ring system is almost perpendicular to the benzene ring [dihedral angle = 87.6 (5)°]. The pyridine ring makes a dihedral angle of 35.5 (5)° with the mean plane of the imidazopyridine fragment. The crystal structure is stabilized by an aromatic π–π stacking interaction between the phenyl rings of neighbouring molecules [centroid–centroid distance = 3.772 (2) Å, interplanar distance = 3.546 (2) Å and slippage = 1.286 (2) Å].
In the title compound, C15H17N3O, the 1H-imidazo[4,5-c]quinoline ring system is approximately planar, with a maximum deviation of 0.036 (1) Å. The C—N—C—C torsion angles formed between this ring system and the isobutyl unit are −99.77 (16) and 79.71 (17)°. In the crystal, intermolecular C—H⋯O hydrogen bonds link the molecules into chains along the c axis.
The two fused five- and six-membered rings building the molecule of the title compound, C13H10BrN3, are approximately planar, the largest deviation from the mean plane being 0.004 (2) Å. The dihedral angle between the imidazo[4,5-b]pyridine mean plane and that of the phenyl ring is 41.84 (11)°. The structure is held together by slipped π–π stacking between symmetry-related molecules, with an interplanar distance of 3.583 (1) Å and a centroid–centroid vector of 3.670 (2) Å.
In the title compound, C21H20N4O2, the statistically planar 1H-limidazole ring [maximum deviation = 0.003 (1) Å] makes dihedral angles of 1.33 (9) and 8.23 (7)°, respectively, with the essentially planar fused pyridine ring [maximum devation = 0.018 (1) Å] and the pendant benzene ring, which is attached to the pyridine ring by an —NH— group. An intramolecular C—H⋯N interaction, which generates an S(6) ring, helps to estalish the molecular conformation. In the crystal, the molecules are linked by N—H⋯O, C—H⋯O and O—H—N hydrogen bonds, which generate bifurcated R
2(6) and R
2(9) ring motifs, resulting in supramolecular  chains. The crystal structure also features weak π–π stacking [centroid–centroid distance = 3.5943 (9) Å] and C—H⋯π interactions.
The structure of the title trifluoroacetic acid adduct, C17H12N2O3·C2HF3O2, contains a trifluoroacetic acid molecule hydrogen bonded to the imine N atom of the imidazole ring of a nearly planar four-fused-ring system (r.m.s. deviatiation = 0.013 Å). The carboxylic acid group of the triflouroacetic acid molecule is twisted with respect to the mean plane of the four-fused-ring sytem by 75.9 (2)°. A short intramolecular C—H⋯O hydrogen bond occurs. In the crystal, the adduct molecules are arranged into stacks along the b axis via π–π interactions between imidazole rings and between imidazole and one of the benzene rings [centroid–centroid distances 3.352 (2) and 3.485 (2) Å, respectively]. Molecules are linked via C—H⋯O hydrogen bonds, forming an alternating polymeric head-to-head/tail-to-tail stepped chain approximately along the a-axis direction and tilted on an axis bisecting the b and c axes.
The title compound, C18H12N2O, comprises two aromatic fragments, viz., imidazo[2,1-a]isoquinoline and benzene, linked by oxygen and methylene bridges. Despite the absence of a common conjugative system within the molecule, it adopts an essentially planar conformation with an r.m.s. deviation of 0. 036 Å. In the crystal, due to this structure, molecules form stacks along the b axis by π⋯π stacking interactions, with shortest C⋯C distances in the range 3.340 (4)–3.510 (4) Å. The molecules are bound by intermolecular C—H⋯O interactions within the stacks and C—H⋯π interactions between the stacks.
In the title compound, C15H17N3OS, the dihedral angle between the statistically planar imidazo[2,1-b][1,3,4]thiadiazole fused-ring system (r.m.s. deviation = 0.002 Å) and the methyoxbenzene ring is 4.52 (6)°. In the crystal, molecules are arranged into columns and stacked down the a axis. The crystal structure is stabilized by weak C—H⋯π and π–π interactions [centroid–centroid separations = 3.6053 (8) and 3.7088 (7) Å].
In the title compound, C14H15N3S, the imidazo[2,1-b][1,3,4]thiadiazole fused-ring system is close to planar, with a maximum deviation of 0.042 (1) Å, and the dihedral angle between it and the phenyl ring is 24.21 (6)°. The isobutyl group is disordered over two sets of sites in a 0.899 (9):0.101 (9) ratio. In the crystal, weak aromatic π–π stacking interactions involving the imidazole and thiadiazole rings with a centroid–centroid distance of 3.8067 (7) Å occur.
The reaction of propargyl bromide and 6-bromo-1,3-dihydroimidazo[4,5-b]pyridin-2-one in refluxing dimethylformamide yields the title compound, C12H8BrN3O, which features nitrogen-bound propadienyl and propynyl substituents. The imidazolopyridine fused ring is planar (r.m.s. deviation = 0.012 Å); the propadienyl chain is coplanar with the fused ring as it is conjugated with it, whereas the propynyl chain is not as the nitrogen-bound C atom is a methylene linkage. The acetylenic H atom is hydrogen bonded to the carbonyl O atom of an adjacent molecule, forming a helical chain runnning along the b axis.
In the title compound, C20H22BrN5O2·2H2O, the Schiff base molecule exists in an E conformation with respect to the acyclic C=N bond. An S(6) ring motif is formed via an intramolecular O—H⋯N hydrogen bond. The dihedral angle between the imidazo[1,2-a]pyridine system and the benzene ring is 84.62 (5)°. In the crystal, N—H⋯O, O—H⋯O, O—H⋯N, C—H⋯O and C—H⋯Br hydrogen bonds link the molecules into a three-dimensional network. The crystal packing is further stabilized by C—H⋯π and π–π interactions [centroid–centroid distance = 3.5365 (7) Å].
In the title compound, C10H6F3N3, the imidazo[1,2-a]pyridine group is essentially planar with a maximum deviation of 0.021 (1) Å. The F atoms in the trifluoromethyl group and the methyl H atoms are each disordered over two sets of sites with refined site occupancies of 0.68 (1):0.32 (1). In the crystal, molecules are linked into infinite chains through two C—H⋯N interactions forming R
2(12) and R
2(8) hydrogen-bond ring motifs. These chains are stacked along the a axis.
In the title molecule, C17H15BrN4O2, the fused-ring system is essentially planar, the largest deviation from the mean plane being 0.015 (2) Å, and forms dihedral angles of 37.8 (2) and 35.5 (2)° with the phenyl and oxazolidine rings, respectively. The conformation adopted by the molecule is stabilized by an intramolecular π⋯π interaction [centroid–centroid distance = 3.855(2) Å] between oxazolidine and phenyl rings. The crystal packing features intermolecular C—H⋯N and C—H⋯O interactions.
In the title compound, C14H10N2O, the dihedral angle between the imidazo[1,2-a]pyridine and phenyl rings is 28.61 (4)° The molecules are connected into broad chains parallel to the a axis by weak C—H⋯O and C—H⋯N hydrogen bonds. The linking of the ribbons is provided by π–π stacking interactions between neighbouring pyridine rings, with a centroid–centroid distance of 3.7187 (7) Å.
The title compound, C27H18N4O·2CH4O, is a unsymmetrically substituted quinoxaline. An intramolecular O—H⋯N hydrogen bond involving the hydroxy and imino groups generates an S(6) ring motif. Intermolecular C—H⋯O and N—H⋯O hydrogen bonds form an R
1(7) ring motif involving a methanol O atom and two H atoms of the imidazole and benzene rings, respectively. The latter links neighbouring molecules into one-dimensional extended chains along the a axis. The two benzene rings are inclined towards each other, as indicated by the dihedral angle of 52.13 (10)°. The phenol ring is almost coplanar with the basic quinoxaline unit, making a dihedral angle of 2.43 (6)°. The short distances between the centroids of the five- and six-membered rings prove the existence of π–π interactions [centroid–centroid distances = 3.5234 (9)–3.7885 (10) Å]. The crystal structure is stabilized by intramolecular O—H⋯N, intermolecular O—H⋯O, N—H⋯O and C—H⋯O (× 2) hydrogen bonds and weak intermolecular C—H⋯π and π–π interactions.
In the title compound, C14H17N5, the 1H-imidazo[4,5-c]quinoline ring system is essentially planar, with a maximum deviation of 0.0325 (7) Å. In the crystal, a pair of intermolecular N—H⋯N hydrogen bonds link neighbouring molecules, forming an inversion dimer and generate an R
2(10) ring motif. These dimers are further connected into a chain along the b axis via intermolecular C—H⋯N hydrogen bonds, resulting in an R
2(14) ring motif.
In the title compound, C20H14N4, all the non-H atoms are roughly coplanar with an r.m.s. deviation of 0.0776 Å. In the crystal, molecules are linked by N—H⋯N hydrogen bonds, forming chains along the (). The chains are connected by intermolecular C—H⋯N hydrogen bonds and π–π stacking interactions between inversion-related phenanthroline, imidazole and phenyl rings with centroid–centroid distances in the range 3.777 (1)–3.905 (1) Å.
In the title compound, C21H20ClN5·H2O, the 1H-imidazo[4,5-c]quinoline ring is approximately planar, with a maximum deviation of 0.0795 (7) Å, and it forms a dihedral angle of 7.65 (3)° with the chlorophenyl ring. In the crystal, the components are linked into chains along the a axis via intermolecular N—H⋯O, O—H⋯N and C—H⋯O hydrogen bonds. One of the H atoms of the water molecule is disordered over two positions with a site-occupancy ratio of 0.80 (4):0.20 (4).
The fused imidazole and pyridine rings in the title compound, C13H10BrN3O, are linked to a benzyl group. The fused ring system is essentially planar, the largest deviation from the mean plane being 0.006 (2) Å. The phenyl ring is not coplanar with the fused ring system, as indicated by the dihedral angle of 67.04 (12)°. In the crystal, molecules are linked by pairs of N—H⋯O hydrogen bonds, forming inversion dimers.
In the title compound, C14H16BrN3O5, the N atoms adjacent to the carbonyl group in the five-membered ring are substituted by (1,3-dioxolan-2-yl)methyl groups. The fused ring system is essentially planar, with the largest deviation from the mean plane being 0.014 (2) Å for the C atom bearing the Br atom. The first oxolane ring, attached on the side of the N atom belonging to the pyridine ring, has an envelope conformation with one of the O atoms as the flap, whereas the second oxolane ring displays a twisted boat conformation. The two oxolane rings display envelope and twisted boat conformations. In the crystal, molecules are linked by C—H⋯O hydrogen bonds, building chains parallel to the a-axis direction.
In the molecule of the title compound, C12H15BrN4O2, the imidazole and pyridine rings are strictly coplanar [maximum deviation 0.006 (3) Å]. In the crystal structure, molecules are linked into chains running parallel to the a axis by intermolecular N—H⋯O hydrogen bonds. Centrosymmetrically related chains are further connected by N—H⋯N hydrogen-bonding interactions to form a two-dimensional layer structure parallel to the ab plane.
The title compound, C19H15Cl2N3O2, was obtained by a one-step cyclocondensation of 2-amino-1-(4-chlorophenyl)imidazoline with diethyl (2-chlorobenzyl)malonate under basic conditions. In the crystalline state, the molecule exists as the 7-hydroxy-5-oxo tautomer. The dihedral angles between the fused imidazopyrimidine and aromatic chlorophenyl and chlorobenzyl rings are 14.2 (1) and 70.7 (1)°, respectively. The conformation of the molecule is influenced by the intramolecular C—H⋯O and C—H⋯N hydrogen bonds, giving a nearly planar five-ring fused system [maximum deviation from the mean plane = 0.296 (2) Å]. In the crystal structure, strong intermolecular O—H⋯O hydrogen bonds link the molecules into chains along the c axis. These chains are further stabilized by weak C—H⋯Cl and π–π interactions [centroid–centroid distance = 3.6707 (12) Å].
The room-temperature reaction of propargyl bromide and 6-bromo-1,3-dihydroimidazo[4,5-b]pyridin-2-one in dimethylformamide yields the title compound, C12H8BrN3O, which features nitrogen-bound propynyl substituents. The imidazopyridine fused ring is almost planar (r.m.s. deviation = 0.011 Å); the propynyl chains point in opposite directions relative to the fused ring. One acetylenic H atom is hydrogen bonded to the carbonyl O atom of an inversion-related molecule, forming a dimer; adjacent dimers are linked by a second acetylene–pyridine C—H⋯N interaction, forming a layer motif.
In the title molecule, C16H11BrN2OS, the central imidazo[2,1-b][1,3]benzothiazole tricycle is essentially planar (r.m.s. deviation = 0.021 Å). The terminal phenyl ring is twisted at 36.18 (5)° from the mean plane of the tricycle. In the crystal, pairs of eak C—H⋯O hydrogen bonds link molecules into centrosymmetric dimers, which are further packed into stacks along the a axis.