Vibrational spectra, HOMO, LUMO, NBO, MEP analysis and molecular docking study of 2,2-diphenyl-4-(piperidin-1-yl)butanamide.

The Fourier-Transform Infrared and Fourier-Transform Raman spectra of 2,2-diphenyl-4-(piperidin-1-yl)butanamide were recorded in the region 4000-400 cm(-1) and 4000-0 cm(-1). The vibrational wavenumbers are computed using HF and DFT methods. The complete vibrational assignments were performed on the basis of potential energy distribution using GAR2PED program. The geometrical parameters of the title compound are in agreement with the XRD data. From the MEP study, the negative electrostatic potential regions are mainly localized of carbonyl group and are possible sites for electrophilic attack and the positive regions are localized all the rings, indicating possible sites for nucleophilic attack. Stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using natural bond orbital analysis. The calculated HOMO and LUMO energies also confirm that charge transfer occurs within the molecule. PASS analysis of the title compound predicts among other activities, antidyskinetic activity. Molecular docking results draw us to the conclusion that the compound might exhibit inhibitory activity against adenosine A2A and may act as antidyskinetic agent.

Crystal structure of 3-benzoyl-2-[(5-bromo-2-hydroxy-3-meth-oxy-benzyl-idene)amino]-4,5,6,7-tetra-hydro-benzo[b]thio-phene.

In the cyclo-hexene ring of the title compound, C23H20BrNO3S, the -(CH2)4- atoms are positionally disordered [occupancy ratio = 0.753 (6):0.247 (6)]. The ring has a half-chair conformation for both the major and minor components. The dihedral angles between the mean plane of the thio-phene ring and those of the benzene and phenyl rings are 35.2 (4) and 57.7 (3)°, respectively. The planes of the two aryl rings are twisted with respect to each other by 86.4 (6)°. In the mol-ecule, there is an O-H⋯N hydrogen bond forming an S(6) ring motif. In the crystal, mol-ecules are linked via C-H⋯O hydrogen bonds, forming chains parallel to [100].

Vibrational spectroscopic studies and molecular docking of 10,10-Dimethylanthrone.

FT-IR and FT-Raman spectra of 10,10-Dimethylanthrone were recorded and analyzed. The vibrational wavenumbers were computed using DFT quantum chemical calculations. The data obtained from wavenumber calculations are used to assign vibrational bands obtained experimentally. In its most stable form, the title compound maintains C2v symmetry as determined by XRD results, where both methyl groups are staggered with respect to the corresponding C23-C24 and C23-C28 bonds. The geometrical parameters (B3LYP/6-311++G(d,p)(5D,7F)) of the title compound are in agreement with the XRD results. The calculated HOMO and LUMO energies allow the calculations of atomic and molecular properties and they also showed that charge transfer occurs in the molecule. A detailed molecular picture of the title compound and its interactions were obtained from NBO analysis. As seen from the MEP map, negative potential regions are localized over the carbonyl group and are possible sites for electrophilic attack. The title compound, 10,10-Dimethylanthrone forms a stable complex with human topoisomerase-II as is evident from the ligand-receptor interactions and show appreciable antineoplastic activity.

Spectroscopic investigation (FT-IR, FT-Raman and SERS), vibrational assignments, HOMO-LUMO analysis and molecular docking study of Opipramol.

FT-IR and FT-Raman spectra of Opipramol were recorded and analyzed. SERS spectrum was recorded in silver colloid. The vibrational wave numbers were computed using DFT quantum chemical calculations. The data obtained from wave number calculations are used to assign vibrational bands obtained in infrared and Raman spectra as well as in SERS of the studied molecule. Potential energy distribution was done using GAR2PED program. The geometrical parameters (DFT) of the title compound are in agreement with the XRD results. The presence of CH2 stretching modes in the SERS spectrum indicates the close of piperazine ring with the metal surface and the interaction of the silver surface with this moiety. NBO analysis, HOMO-LUMO, first hyperpolarizability and molecular electrostatic potential results are also reported. The inhibitor Opipramol forms a stable complex with P4502C9 as is evident from the ligand-receptor interactions and a -9.0 kcal/mol docking score and may be an effective P4502C9 inhibitor if further biological explorations are carried out.

Crystal structures of 4-(pyrimidin-2-yl)piperazin-1-ium chloride and 4-(pyrimidin-2-yl)piperazin-1-ium nitrate.

The title salts, C8H13N4 (+)·Cl(-), (I), and C8H13N4 (+)·NO3 (-), (II), contain linked pyridinium-piperazine heterocycles. In both salts, the piperazine ring adopts a chair conformation with protonation at the N atom not linked to the other ring. In the crystal of (I), weak N-H⋯Cl inter-actions are observed, leading to zigzag chains along [100]. In the crystal of (II), both H atoms on the NH2 (+) group form bifurcated N-H⋯(O,O) hydrogen bonds. Weak C-H⋯O inter-actions are also observed. These bonds collectively link the components into infinite chains along [100].

Crystal structure of 1-(3-chloro-phen-yl)piperazin-1-ium picrate-picric acid (2/1).

The title salt {systematic name: bis-[1-(3-chloro-phen-yl)piperazinium 2,4,6-tri-nitro-phenolate]-picric acid (2/1)}, 2C10H14ClN2 (+)·2C6H5N3O7 (-)·C6H6N3O7, crystallized with two independent 1-(3-chloro-phen-yl)piperazinium cations, two picrate anions and a picric acid mol-ecule in the asymmetric unit. The six-membered piperazine ring in each cation adopts a slightly distorted chair conformation and contains a protonated N atom. In the picric acid mol-ecule, the mean planes of the nitro groups in the ortho-, meta-, and para-positions are twisted from the benzene ring by 31.5 (3), 7.7 (1), and 3.8 (2)°, respectively. In the anions, the dihedral angles between the benzene ring and the ortho-, meta-, and para-nitro groups are 36.7 (1), 5.0 (6), 4.8 (2)°, and 34.4 (9), 15.3 (8), 4.5 (1)°, respectively. The nitro group in one anion is disordered and was modeled with two sites for one O atom with an occupancy ratio of 0.627 (7):0.373 (7). In the crystal, the picric acid mol-ecule inter-acts with the picrate anion through a trifurcated O-H⋯O four-centre hydrogen bond involving an intra-molecular O-H⋯O hydrogen bond and a weak C-H⋯O inter-action. Weak inter-molecular C-H⋯O inter-actions are responsible for the formation of cation-anion-cation trimers resulting in a chain along [010]. In addition, weak C-H⋯Cl and weak π-π inter-actions [centroid-centroid distances of 3.532 (3), 3.756 (4) and 3.705 (3) Å] are observed and contribute to the stability of the crystal packing.

Crystal structure of 3-[4-(pyrimidin-2-yl)piperazin-1-ium-1-yl]butano-ate.

The title compound, C12H18N4O2, crystallizes in the zwitterionic form with protonation at the N atom of the piperazine ring bearing the carboxylate group. The piperazine ring adopts a slightly distorted chair conformation. In the crystal, N-H⋯O hydrogen bonds are observed, forming chains along [010]. The packing is consolidated by C-H⋯O inter-actions, which generate a three-dimensional network.

Two tautomers in the same crystal: 3-(4-fluoro-phen-yl)-1H-pyrazole and 5-(4-fluoro-phen-yl)-1H-pyrazole.

The title co-crystal, 3-(4-fluoro-phen-yl)-1H-pyrazole-5-(4-fluoro-phen-yl)-1H-pyrazole (1/1), C9H7FN2, crystallizes with four independent mol-ecules (A, B, C and D) in the asymmetric unit exhibiting two tautomeric forms (A and D; B and C) due to N-H proton exchange between the two N atoms of the pyrazole ring. The dihedral angles between the mean planes of the pyrazole and benzene rings are 15.6 (1), 19.8 (9), 14.0 (1) and 10.7 (7)° in mol-ecules A, B, C and D, respectively. In the crystal, N-H⋯N hydrogen bonds link the four mol-ecules in the asymmetric unit into a ring with an R 4 (4)(12) motif. Furthermore, weak C-H⋯F inter-actions link the mol-ecules into a three-dimensional network.

Crystal structure of N-(3-benzoyl-4,5,6,7-tetra-hydro-1-benzo-thio-phen-2-yl)benzamide.

In the title compound, C22H19NO2S, the cyclo-hexene ring adopts a half-chair conformation. The dihedral angles between the plane of the thio-phene ring and those of its amide- and carbonyl-bonded benzene rings are 7.1 (1) and 59.0 (2)°, respectively. An intra-molecular N-H⋯O hydrogen bond generates an S(6) ring. In the crystal, very weak aromatic π-π stacking inter-actions [centroid-centroid separation = 3.9009 (10) Å] are observed.

N-(1,5-Dimethyl-3-oxo-2-phenyl-2,3-di-hydro-1H-pyrazol-4-yl)-2-(4-nitro-phen-yl)acetamide.

In the title compound, C19H18N4O4, the nitro-phenyl and phenyl rings are twisted by 67.0 (6) and 37.4 (4)°, respectively, with respect to the pyrazole ring plane [maximum deviation = 0.0042 (16) Å]. The dihedral angle between the mean planes of the phenyl rings is 59.3 (3)°. The amide group, with a C-N-C-C torsion angle of 177.54 (13)°, is twisted away from the plane of the pyrazole ring in an anti-periplanar conformation. In the crystal, N-H⋯O hydrogen bonds involving the carbonyl group on the pyrazole ring and the amide group, together with weak C-H⋯O inter-actions forming R 2 (2)(10) graph-set motifs, link the mol-ecules into chains along [100]. Additional weak C-H⋯O inter-actions involving the nitro-phenyl rings further link the mol-ecules along [001], also forming R 2 (2)(10) graph-set motifs, thereby generating (010) layers.

Flunarizinium isonicotinate.

In the cation of the title salt {systematic name: 4-[bis-(4-fluoro-phen-yl)meth-yl]-1-[(2E)-3-phenyl-prop-2-en-1-yl]piperazin-1-ium pyridine-4-carboxyl-ate}, C26H27F2N2 (+)·C6H4NO2 (-), the piperazine ring is in a slightly distorted chair conformation. The dihedral angle between the mean planes of the fluoro-substituted benzene rings is 81.9 (1)° and these benzene rings form dihedral angles of 6.5 (1) and 87.8 (1)° with the phenyl ring. In the crystal, a single N-H⋯O hydrogen bond links the cation and the anion. In addition, weak C-H⋯O hydrogen bonds and π-π stacking inter-actions involving one of the fluoro-substituted benzene rings and the phenyl ring, with a centroid-centroid distance of 3.700 (7) Å, link mol-ecules along [100].

Pyrimethaminium 2-{[4-(tri-fluoro-meth-yl)phen-yl]sulfan-yl}benzoate dimethyl sulfoxide monosolvate.

In the cation of the title solvated mol-ecular salt, C12H14ClN4 (+)·C14H8F3O2S(-)·C2H6OS [systematic name of the cation: 2,4-di-amino-5-(4-chloro-phen-yl)-6-ethyl-pyrimidin-1-ium], the dihedral angle between the planes of the pyrimidinium and 4-chloro-phenyl rings is 77.2 (5)°. In the anion, the planes of the benzene rings are twisted with respect to each other by 71.5 (5)°. Disorder was modelled for the dimethyl sulfoxide solvent mol-ecule over two set of sites in a 0.7487 (13):0.2513 (13) ratio. In the crystal, the cations are linked by inversion-generated pairs of N-H⋯N hydrogen bonds, with an R 2 (2)(8) graph-set motif. The cation donates two N-H⋯O hydrogen bonds to the anion, also generating an R 2 (2)(8) loop. These inter-actions, along with cation-solvent N-H⋯O hydrogen bonds, and cation-anion C-H⋯F, solvent-anion C-H⋯O and C-H⋯F inter-actions, result in a three-dimensional network.

4-(Furan-2-carbon-yl)piperazin-1-ium 3,5-di-nitro-benzoate.

In the cation of the title salt, C9H13N2O2 (+)·C7H3N2O6 (-), the piperazine ring adopts a slightly distorted chair conformation. Twofold rotational disorder is exhibited by the furan ring in a 0.430 (4):0.570 (4) ratio. In the crystal, N-H⋯O hydrogen bonds link the ions into chains along [010]. Additional weak C-H⋯O inter-actions are observed, leading to a supra-molecular layer parallel to (011).

4-(Pyrimidin-2-yl)piperazin-1-ium (E)-3-carb-oxy-prop-2-enoate.

In the cation of the title salt, C8H13N4 (+)·C4H3O4 (-), the piperazinium ring adopts a slightly distorteded chair conformation. In the crystal, a single strong O-H⋯O inter-molecular hydrogen bond links the anions, forming chains along the c-axis direction. The chains of anions are linked by the cations, via N-H⋯O hydrogen bonds, forming sheets parallel to (100). These layers are linked by weak C-H⋯O hydrogen bonds, forming a three-dimensional structure. In addition, there are weak π-π inter-actions [centroid-centroid distance = 3.820 (9) Å] present involving inversion-related pyrimidine rings.

{2-[(4-Nitro-benzyl-idene)amino]-4,5,6,7-tetrahydro-1-benzo-thio-phen-3-yl}(phen-yl)methanone.

In the title compound, C22H18N2O3S, disorder is found in the benzoyl group (A and B), as well as for four C atoms of the cyclo-hexene ring. Two orientations were modeled in a 0.583 (5):0.417 (5) ratio. The cyclo-hexene ring is in a distorted chair conformation. The dihedral angles between the mean plane of the thio-phene ring and the 4-nitro-benzene and phenyl rings are 30.9 (8) and 64.8 (3) (A) and 62.4 (7)° (B). The mean planes of the 4-nitro-benzene and the phenyl rings are almost perpendicular to each other, with dihedral angles of 85.4 (1) (A) and 83.9 (8)° (B). An extensive array of weak C-H⋯O inter-actions consolidate mol-ecules into a three-dimensional architecture, forming chains along [001] and [010] and layers parallel to (011).

Theoretical investigations on the molecular structure, vibrational spectral, HOMO-LUMO and NBO analysis of 9-[3-(Dimethylamino)propyl]-2-trifluoro-methyl-9H-thioxanthen-9-ol.

The experimental FT-IR and FT-Raman spectra of 9-[3-(Dimethylamino)propyl]-2-trifluoro-methyl-9H-thioxanthen-9-ol have been recorded. Quantum chemical calculations of geometry and vibrational wavenumbers of 9-[3-(Dimethylamino)propyl]-2-trifluoro-methyl-9H-thioxanthen-9-ol are carried out theoretically. Four possible stable conformations of the title compound were determined. In terms of the conformational analysis, one of the most interesting structural features of the title compound is the intra molecular OH⋯N hydrogen bond. The barrier of planarity between the most stable and planar form is also predicted. The optimized geometrical parameters obtained by B3LYP method show a good agreement with XRD data. The difference between the observed and theoretical wavenumbers is very small. The complete assignments were performed on the basis of potential energy distribution of the vibrational modes calculated theoretically. The calculated HOMO and LUMO energies allow the calculation of atomic and molecular properties and they also showed that charge transfer occurs in the molecule. A detailed molecular picture of the title compound and its interactions were obtained from NBO analysis. As seen from the MEP map, negative potential regions are over the hydroxyl group and positive potential regions are over the methyl groups.

{2-[(2-Bromo-5-meth-oxy-benzyl-idene)amino]-4,5,6,7-tetra-hydro-benzo[b]thiophen-3-yl}(phen-yl)methanone.

In the title compound, C23H20BrNO2S, disorder was modeled for the outer two C atoms of the cyclo-hexene ring over two sets of sites with an occupancy ratio of 0.580 (11):0.420 (11). Both rings have a half-chair conformation. The dihedral angles between the mean plane of the thio-phene ring and the benzene and phenyl rings are 9.2 (2) and 66.1 (2)°, respectively. The benzene and phenyl rings are inclined to each other by 74.8 (8)°. In the crystal, mol-ecules are linked by pairs of C-H⋯O hydrogen bonds, forming inversion dimers.

5-(4-Fluoro-phen-yl)-2H-pyrazol-1-ium 2,2,2-tri-fluoro-acetate.

The title salt, C9H8FN2 (+)·C2F3O2 (-), crystallizes with two independent cations (A and B) and two independent anions (C and D) in the asymmetric unit. In the cations, the dihedral angles between the benzene and pyrazolium rings are 23.7 (3)° in cation A and 1.8 (8)° in cation B. In the crystal, each anion links to the two cations via N-H⋯O hydrogen bonds, forming a U-shaped unit with an R 4 (4)(14) ring motif. These U-shaped units stack along the a axis and are linked via C-H⋯O and C-H⋯F hydrogen bonds, forming slabs lying parallel to (100). Within the slabs there are π-π inter-actions between the pyrazolium rings [inter-centroid distance = 3.6326 (15) Å] and between the benzene rings [inter-centroid distance = 3.7244 (16) Å]. In the anions, the F atoms of the tri-fluoro-methyl groups are disordered over two sets of sites, with refined occupancy ratios of 0.58 (3):0.42, 0.540 (14):0.46 (14), and 0.55 (2):0.45 (2) for anion C, and 0.73 (5):0.27 (5), 0.63 (5):0.37 (5), and 0.57 (8):0.43 (8) for anion D.

{2-[(2-Hy-droxy-benzyl-idene)amino]-4,5,6,7-tetra-hydro-1-benzo-thio-phen-3-yl}(phen-yl)methanone.

In the title compound, C22H19NO2S, the cyclo-hexene ring adopts a slightly distorted half-chair conformation. The dihedral angles between the mean planes of the thio-phene ring and the phenyl and 2-hy-droxy-phenyl rings are 70.4 (5) and 12.1 (9)°, respectively. The phenyl and 2-hy-droxy-phenyl rings are twisted with respect to one another by 81.0 (6)°. A short intra-molecular O-H⋯N hydrogen bond is observed. In the crystal, weak C-H⋯O inter-actions link the mol-ecules into zigzag chains diagonally along [100] .

(4-Methyl-piperazin-1-yl)(2,3,4-tri-meth-oxy-benzyl-idene)amine.

In the title compound, C15H23N3O3, the piperazine ring is in a slightly distorted chair conformation and is twisted from the mean plane of the benzene ring making a dihedral angle of 14.94 (6)°. The 4-meth-oxy substituent is almost co-planar with the benzene ring [C-C-O-C torsion angle = 5.4 (1)°], while the meth-oxy groups at positions 2 and 3 [C-C-O-C torsion angles of 122.6 (4) and -66.1 (4)°, respectively] are twisted away from the mean plane of the benzene ring in anti-clinical and synclinical conformations, respectively. No classical hydrogen bonds or any weak inter-molecular inter-actions are observed in the crystal structure.