RESUMO
Three coordination compounds of quinazolin-4(3H)-one (quinoz; C8H6N2O) with divalent group 12 halides are reported. In all complexes, coordination occurs via the nitro-gen atom ortho to the quinazolinone carbonyl group. In the two chain polymers with composition [MX 2(quinoz)], viz. (M = Cd, X = Br), catena-poly[[[quinazolin-4(3H)-one-κN 3]cadmium(II)]-di-µ-bromido], [CdBr2(C8H6N2O)]n (I), and M = Hg, X = Cl, catena-poly[[[quinazolin-4(3H)-one-κN 3]mercury(II)]-di-µ-chlorido], [HgCl2(C8H6N2O)]n (II), the divalent cations are five-coordinate, with four bridging halide and one terminal quinoz ligand. The CdII atom in (I) has an almost trigonal-bipyramidal coordination environment, whereas the HgII atom in (II) has a more distorted coordination environment. Likewise, the halide bridges in (II) are significantly more asymmetric than in (I). In both (I) and (II), quinoz ligands at adjacent cations along each strand are oriented in opposite directions, and the organic ligands of neighboring strands inter-digitate with resulting π-π inter-actions. In contrast to the halide-bridged chain polymers (I) and (II), the adduct of quinoz with CdI2 is the tetra-hedral complex [CdI2(quinoz)2], di-iodido-bis-[quinazolin-4(3H)-one-κN 3]cadmium(II), [CdI2(C16H12N4O2)], (III). The CdII atom in this discrete complex is located on a twofold rotation axis. Disorder in (III) is reflected in an alternative minority orientation of the mol-ecules for which the iodine sites closely match the position of the majority orientation. In view of the low site occupancy of only 0.0318â (8)â Å, only the CdII position for this alternative orientation was taken into account during refinement. In all three compounds, classical N-Hâ¯O hydrogen bonds with donor-acceptor distances of ca 2.9â Å occur; they link the polymer chains in (I) and (II) into di-periodic networks and connect adjacent discrete complexes in (III) to mono-periodic strands.
RESUMO
The title compound, C12H13N3OS, was synthesized via the Willgerodt-Kindler method. The benzimidozole moiety is essentially planar (r.m.s. deviation = 0.0084â Å). The thio-amide group is inclined by 54.80â (14)° to the benzimidazole ring system. The morpholine ring is disordered over two sets of sites [ratio 0.841â (11):0.159â (11)], with chair conformations for both components. In the crystal, mol-ecules are linked into N-Hâ¯N hydrogen-bonded chains running parallel to the c axis. Hirshfeld surface analysis was used to qu-antify the inter-molecular inter-actions.
RESUMO
The asymmetric unit of the title compound, C16H13N3OS, comprises two mol-ecules (A and B) with similar conformations that differ mainly in the orientation of the phenyl group relative to the rest of the mol-ecule, as expressed by the Cthio-amide-Nthio-amide-Cphen-yl-Cphen-yl torsion angle of 49.3â (3)° for mol-ecule A and of 5.4â (3)° for mol-ecule B. In the crystal, two inter-molecular N-Hâ¯N hydrogen bonds lead to the formation of a dimer with R 2 2(10) graph-set notation. A Hirshfeld surface analysis revealed that Hâ¯H inter-actions are the most important inter-molecular inter-actions, contributing 40.9% to the Hirshfeld surface.
RESUMO
The title compounds, 6-nitro-quinazolin-4(3H)-one (C8H5N3O3; I), 6-amino-quinazolin-4(3H)-one (C8H7N3O; II) and 4-amino-quinazolin-1-ium chloride-4-amino-quinazoline-water (1/1/2), (C8H8N3 +·Cl-·C8H7N3·2H2O; III) were synthesized and their structures were determined by single-crystal X-ray analysis. In the crystals of I and II, the quinazoline mol-ecules form hydrogen-bonded dimers via N-Hâ¯O inter-actions. The dimers are connected by weak inter-molecular C-Hâ¯N and C-Hâ¯O hydrogen bonds, forming a layered structure in the case of I. In the crystal of II, N-Hâ¯N and C-Hâ¯O inter-actions link the dimers into a three-dimensional network structure. The asymmetric unit of III consists of two quinazoline mol-ecules, one of which is protonated, a chloride ion, and two water mol-ecules. The chloride anion and the water mol-ecules form hydrogen-bonded chains consisting of fused five-membered rings. The protonated and unprotonated quinazolin mol-ecules are linked to the chloride ions and water mol-ecules of the chain by their amino groups.
RESUMO
The title compound, (C12H15N2)2[ZnCl4], is a salt with two symmetrically independent, essentially planar heterocyclic cations and a slightly distorted tetra-hedral chloro-zincate dianion. N-Hâ¯Cl hydrogen bonds link these ionic constituents into a discrete aggregate, which comprises one formula unit. The effect of hydrogen bonding is reflected in the minor distortions of the [ZnCl4]2- moiety: distances between the cation and chlorido ligands engaged in classical hydrogen bonds are significantly longer than the others. Secondary inter-actions comprise C-Hâ¯π hydrogen bonding and weak π-π stacking. A Hirshfeld surface analysis indicates that the most abundant contacts in packing stem from Hâ¯H (47.8%) and Clâ¯H/Hâ¯Cl (29.3%) inter-actions.
RESUMO
The crystal structures of three mackinazolinone derivatives (2-amino-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-one at room temperature, and 2-nitro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-one and N-(11-oxo-6,8,9,11-tetrahydro-7H-pyrido[2,1-b]quinazolin-2-yl)benzamide at 100â K) are explored using X-ray crystallography. To delineate the different intermolecular interactions and the respective interaction energies in the crystal architectures, energy framework analyses were carried out using the CE-B3LYP/6-31G(d,p) method implemented in the CrystalExplorer software. In the structures the different molecules are linked by C-H...O, C-H...N and N-H...O hydrogen bonds. Together with these hydrogen bonds, C-H...π and C-O...π interactions are involved in the formation of a three-dimensional crystal network. A Hirshfeld surface analysis allows the visualization of the two-dimensional fingerprint plots and the quantification of the contributions of H...H, H...C/C...H and H...O/O...H contacts throughout the different crystal structures. To obtain additional information on the intrinsic properties of our targets and to compare the experimental crystal structures with their respective conformations in the gas phase, quantum chemical calculations at the B3LYP-D3BJ/6-311++G(d,p) level of theory, including Grimme's D3 correction term and BJ damping functions, were carried out to account for intramolecular dispersion interactions. The identified energy gaps between the highest occupied and the lowest unoccupied molecular orbitals (HOMO-LUMO gap) of our targets in the gas phase and in two implicit solvents (methanol and dimethyl sulfoxide) allow us to quantify the impact of different substituents on the reactivity of mackinazolinone derivatives.
RESUMO
The structures and anticancer effects of two sesquiterpene lactones, 1 R,10S,3S,4R-diepoxyguai-5S,6S,7S-11(13)-en-6,12-olide (1) and hanphyllin (2) isolated from the aerial part of Tanacetopsis karataviensis (Kovalevsk.) Kovalevsk were investigated. The compound 1 was isolated for the first time as a natural compound and its structure was investigated by HR-ESI-MS, IR and NMR techniques. The X-ray diffraction analysis was performed to accurately determine the spatial structures of 1 and 2. Furthermore, we evaluated the cytotoxic activity of 1 and 2, and the chloroform fraction which contains both of them. Cytotoxic activity revealed that the effect of the chloroform fraction is stronger in growth inhibition of HeLa (89.7%) and HEp-2 (63.0%) cancer cells than the effect of individual compounds 1 (55.9 and 36.3%), 2 (78.6 and 50.3%) and the reference cisplatin (58.0 and 46.8%) respectively. Moreover, the chloroform fraction is less toxic to the hepatocytes.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Asteraceae/química , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Antineoplásicos Fitogênicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Lactonas/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Componentes Aéreos da Planta/química , Extratos Vegetais/química , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
A quinazolinthione, C17H14N2OS, was synthesized by the condensation reaction of 6,7,8,9-tetra-hydro-11H-pyrido[2,1-b]quinazolin-11-thione with furfural. The mol-ecule crystallizes in the monoclinic system (Cc space group) and has an E configuration with respect to the exocyclic C=C bond. In the crystal, mol-ecules are linked through C-Hâ¯π(furan) inter-actions, forming zigzag chains propagating along the [001] direction.
RESUMO
Selective C-formyl-ation of 8,9,10,11-tetra-hydro-pyrido[2',3':4,5]pyrimido[1,2-a]-azepin-5(7H)-one has been studied for the first time. It was revealed that formyl-ation proceeds by the formation of an inter-mediate salt, which due to the re-amination process on treatment with aqueous ammonia transformed into the corresponding (E)-11-(amino-methyl-ene)-8,9,10,11-tetra-hydro-pyrido[2',3':4,5]-pyrimido[1,2-a]azepin-5(7H)-one, C13H14N4O, as an E-isomer. Formyl-ation was carried out by Vilsmeier-Haack reagent and the structure of the synthesized compound was confirmed by X-ray structural analysis, spectroscopic and LC-MS methods. In the mol-ecule, the seven-membered penta-methyl-ene ring adopts a twist-boat conformation.
RESUMO
Natural and synthetic isoquinoline alkaloids display a wide variety of potent biological activities. The title 1-aryl-2-hydroxyethyl-1,2,3,4-tetrahydroisoquinoline, C19H23NO4, crystallizes with two molecules in the asymmetric unit related by pseudo-translation but differing only slightly in conformation. The pseudosymmetry is also reflected in the diffraction pattern. The subset of reflections corresponding to the smaller cell and average structure are on average twice as intense as those subtending the larger cell. Tentative refinement in the subcell leads to a disordered structural model with satisfactory agreement factors and, after appropriate use of restraints, acceptable molecular geometry but significantly larger and more anisotropic displacement parameters. In the correct unit cell, the independent molecules differ with respect to the orientation of the hydroxyethyl group. Intramolecular hydrogen bonding occurs between the hydroxyphenyl group and the N atom.
Assuntos
Alcaloides/química , Tetra-Hidroisoquinolinas/química , Alcaloides/síntese química , Cristalização , Cristalografia por Raios X , Ligação de Hidrogênio , Modelos Moleculares , Conformação Molecular , Tetra-Hidroisoquinolinas/síntese químicaRESUMO
The asymmetric unit of the title solvate, C21H22N2O2·CH3OH, contains one methanol solvent mol-ecule and one mol-ecule of the heterocycle that is built up by the fusion of four six-membered rings A, C, D, E and one five-membered ring B. The indole moiety (rings A and B) is essentially planar, with an r.m.s. deviation of 0.013â Å, whereas rings C and D adopt a twisted conformation with a trans-ring junction. In the crystal, two heterocyclic mol-ecules are associated with two methanol mol-ecules through mutual N-Hâ¯O and O-Hâ¯N hydrogen bonds, forming a centrosymmetric dimer.
RESUMO
The title mol-ecular salt, C15H21N2O(+)·ClO4 (-), crystallizes with four cations (A, B, C and D) and four anions in the chiral unit cell (space group P21). The alkaloid was isolated from the aerial parts of Genista Hispanica collected in the Samarkand region of Uzbekistan. Each cation is protonated at the N atom that bridges the alkaloid rings C and D. In each cation, ring A is almost planar and ring B adops a sofa conformation with the methyl-ene group bridging to the C ring as the flap. Rings C and D adopt chair conformations with a cis ring junction in all four cations. In the crystal, A+B and C+D dimeric pairs linked by pairs of N-Hâ¯O hydrogen bonds are observed, which generate R 2 (2)(16) loops in each case. The dimers are consolidated by weak aromatic π-π stacking inter-actions between the A rings [centroid-centroid distances = 3.913â (3) and 3.915â (3)â Å].
RESUMO
The asymmetric unit of the title hydrated salt, C24H35N2O5 (+)·Cl(-)·2H2O, contains one organic cation that has its protonation site at the amine function, one chloride anion and two lattice water mol-ecules. In the crystal, one pair of lattice water mol-ecules and two chloride anions form a four-membered centrosymmetric hydrogen-bond cycle. In addition, O-Hâ¯O, N-Hâ¯O and N-Hâ¯Cl hydrogen bonds involving the N-H groups, the water mol-ecules and the C=O group are observed. As a result, a hydrogen-bonded layer parallel to (100) is formed. The thickness of such a layer corresponds to the length of the a axis [21.977â (3)â Å].
RESUMO
The title compound, C18H16O8, was isolated from the plant Artemisia baldshuanica Krasch et Zarp. The mol-ecule is approximately planar, with the exception of the terminal methyl groups, the C atoms of which devitate from their attached ring planes by 1.243â (5) and 1.168â (5)â Å. The dihedral angle between the substituted benzopyran and benzene rings is 5.8â (1)°; this near planarity could be due to conjugation or a packing effect. Intra-molecular O-Hâ¯O and C-Hâ¯O hydrogen bonds occur. In the crystal, mol-ecules are connected by O-Hâ¯O hydrogen bonds involving the hy-droxy and carbonyl groups, forming hydrogen-bonded chains along [001] and [1-10]. The chains are linked by C-Hâ¯O inter-actions.
RESUMO
In the title complex, [NiCl(2)(C(8)H(6)N(2)O)(2)(H(2)O)(2)], the Ni(II) ion is located on an inversion center and is six-coordinated by two N atoms of 1H-quinazolin-4-one ligands, two chloride ions and two water mol-ecules. The water mol-ecules are involved in intra- and inter-molecular O-Hâ¯O and O-Hâ¯Cl hydrogen bonding. Inter-molecular N-Hâ¯O and N-Hâ¯Cl hydrogen bonds are formed between ligands. In addition, weak π-π inter-actions are observed between the benzene rings of the ligands [centroid-centroid distance = 3.580â (3)â Å]. The inter-molecular hydrogen bonds and π-π inter-actions lead to the formation of a three-dimensional supra-molecular network.
RESUMO
In the crystal, mol-ecules of the title compound, C(11)H(10)N(2)S, are connected by C-Hâ¯N inter-actions around threefold axes. Furthermore, they form stacks along the c axis showing π-π inter-actions between pyrimidine rings [centroid-centroid distance = 3.721â (1)â Å]. The central ring is essentially planar with an r.m.s. deviation of 0.007â Å. The five-membered ring adopts an envelope conformation with the flap atom deviating by 0.241â (4)â Å from the mean plane (r.m.s. deviation = 0.002â Å) through the other four ring atoms.
RESUMO
In the crystal structure of the title two-dimensional network, [HgCl(2)(C(11)H(10)N(2)O)](n), the asymmetric unit consists of HgCl(2) dumbbells and one mol-ecule of the quinazoline unit. Pseudo-octa-hedrally coordinated Hg(II) cations are chloride-bridged via a crystallographic inversion centre leading to different Hg-Cl bonds (short and long) and linked by other Cl atoms via translation along the a axis. The quinazoline ligands connect the Hg-Cl-Hg-Cl chains by N and O atoms along the b axis, forming the two-dimensional network structure. The crystal structure is stabilized by weak non-classical C-Hâ¯Cl hydrogen bonds and aromatic π-π stacking inter-actions [centroid-centroid distances = 3.942â (4) and 3.621â (4)â Å].
RESUMO
In the crystal structure of the title compound, C(18)H(17)N(3)O(3)·H(2)O, the mol-ecules are linked by O-Hâ¯O and O-Hâ¯N hydrogen bonds, resulting in a chain along the a axis. The crystal structure is stabilized by weak inter-molecular C-Hâ¯π (ring) hydrogen bonds and aromatic πâ¯π stacking inter-actions [centroid-centroid distance = 3.902â (1)â Å] between the pyrimidino rings of the quinazoline system. The tricyclic quinazoline fragment is almost planar (rms deviation = 0.0139â Å) with the two methylene C atoms of the pyrrolo ring deviating by 0.148â (2) and -0.081â (3)â Å from the plane through the other atoms. The 4-nitrophenyl ring makes a dihedral angle of 12.55â (7)° with the tricyclic ring system.
RESUMO
In the mol-ecule of the title compound, C(20)H(16)N(2)O(5), the phthalimide fragments are almost planar, with r.m.s. deviations of 0.018 and 0.020â Å, and make a dihedral angle of 53.64â (3)°. The mol-ecular and crystal structures are stabilized by a weak inter-molecular C-Hâ¯O, C-Hâ¯π and C=Oâ¯π [2.883â (1)â Å] inter-actions and aromatic π-π stacking inter-actions with a centroid-centroid distance of 3.6189â (7)â Å.
RESUMO
The title compound, C(15)H(16)N(2)O(2)·H(2)O, was synthesized via the alkyl-ation of 3-hydroxy-methyl-idene-2,3-dihydro-1H-pyrrolo[2,1-b]quinazolin-9-one with n-propyl iodide in the presence of sodium hydroxide. The organic mol-ecule and the water mol-ecule both lie on a crystallographic mirror plane. In the crystal structure, inter-molecular O-Hâ¯O and O-Hâ¯N hydrogen bonds link the components into extended chains along [100].