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Synthesis of lithium borate glass system was carried using the melt quenching technique with varying concentrations of magnesium followed by analysing the different characteristics such as physical, structural, optical and thermoluminescene using various techniques eg. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), UV-Vis spectroscopy, and Thermoluminescence (TL). The obtained XRD pattern confirmed the amorphous nature of the prepared samples. Relevant physical parameters have been evaluated to study the response of these properties with respect to magnesium content. The density and molar volume values showed that the network structure changed with increasing magnesium content. It is evident from the FTIR spectra that the network of the prepared samples predominantly contains BO3 and BO4 units. The UV-vis spectra confirmed a decrease in the direct and indirect band gap values with increase in MgO content. Optical parameters namely refractive index, electronic polarizability, reflection loss and dielectric constant were also calculated and found to be in good correlation with other studies. Following gamma rays irradiation with different doses, TL glow curves of prepared glasses were analysed. Deconvolution of TL glow curves was done using glow curve convolution deconvolution (GCCD) function and trapping parameters of isolated peaks viz. activation energy and frequency factor have been determined. [ABSTRACT FROM AUTHOR]

• New (fac- [ Re (CO) 3 Br(HL)] compounds with bioactive indole and isatin-based thiosemicarbazones were synthesized. • The compounds showed potent antibacterial activity against the gram-positive Methicillin-resistant (MRSA) and Vancomycin-resistant (VRSA) S. aureus bacteria. • The (fac- [ Re (CO) 3 Br(HL)] species convert into dimer [Re 2 (CO) 6 (L) 2 ] in solution. • Re -thiosemicarbazonate complexes are dimers by re -s- re bridges as confirmed by single crystal x-ray diffraction. Antibiotic resistance is becoming a cause of serious concern to human health causing a significant impact on the global economy. The demand for novel antimicrobial agents is pressing since drug resistance is spreading and making antibiotics less and less effective. There is unrealized antibacterial potential in metal complexes. Among other compounds, rhenium complexes are particularly appealing because of their strong antibacterial activity and minimal in vivo toxicity. In this study, three Re carbonyl thiosemicarbazone (TSC) complexes were synthesized and characterized and their antibacterial potential was evaluated against various types of gram-positive and gram-negative bacteria. The structure of the ligands and their corresponding Re complexes were optimized at the DFT/B3LYP level of theory employing 6–311++ G (d,p) and LANL2DZ basis sets for C, H, N, O, S, and Re atoms respectively. The MS studies performed with time show that [ fac- [ Re (CO) 3 Br(HL)] was converted into dimer [Re 2 (CO) 6 (L) 2 ] in solution and the crystal structure of the dimer [Re 2 (CO) 6 (L) 2 ] obtained as the result of dimerization of the complex was solved. Among the three Re TSC complexes, [ fac- [ Re (CO) 3 Br(HL1)] exhibits the greatest antibacterial activity against S.aureus with MIC value 0.5 µg/mL. The data obtained showed that the synthesized complexes were ineffective against gram-negative bacteria but showed excellent antibacterial activity against gram-positive S.aureus. The [ fac- [ Re (CO) 3 Br(HL2)] complex derived from isatin-β-thiosemicarbazone showed lesser activity than the other two rhenium TSC complexes which were obtained by condensation of indole-2-carboxaldehyde and thiosemicarbazide. Furthermore, the in-silico molecular docking studies revealed that the binding energy of the docked compound [ Re (CO) 3 Br(HL)] with E. Coli and MRSA targets were extremely favorable (-7.18 and -5.67 kcal/mol, respectively which further demonstrates the potential of the synthesized complexes in the development of new antibacterial drugs. The molecular docking studies as well as experimental investigations demonstrate the effect of substituents on the ligand backbone on the antimicrobial activity of the synthesized rhenium carbonyl complexes. The enhanced antibacterial properties of rhenium carbonyl complexes with the TSC ligands in comparison to the ligand alone also suggest a possible synergistic effect of the metal center and the organic ligand. [Display omitted] [ABSTRACT FROM AUTHOR]

The title compound, [Eu(C9H10BN6)(C19H15O2)2(C3H7NO)] or [TpEu(Anthracac)2(DMF)], was synthesized by reaction of a tris(pyrazolyl)borate (Tp-) Eu3+ complex with 3-(anthracen-9-yl)pentane-2,4-dione (HAnthracac) in the presence of triethylamine. In the title compound, Eu3+ is located in an octavertex square-pyramidal coordination environment. In the two Anthracac-ligands, the anthracene and nearly planar acetylacetonate fragments are almost orthogonal. Neighboring molecules of TpEu(Anthracac)2(DMF) are connected in the crystal by intermolecular van der Waals interactions, while π-stacking interactions are limited to the edges of two anthracene rings. [ABSTRACT FROM AUTHOR]

In the title compounds C23H21ClN2O3 [I, namely 1-(4-chlorophenyl)-4-(4-methylphenyl)-3,8-dioxo-1,2,5,6,7,8-hexahydroquine-3-carboxylic acid] and C24H22N2O3 [II, namely 4-(4-methoxyphenyl)-1-(4-methylphenyl)-2,5-dioxo-1,2,5,6,7,8-hexahydroquinoline-3-carbonitrile], each of the cyclohexene and dihydropyridine rings of the 1,2,5,6,7,8-hexahydro-quinoline moieties adopts a twisted-boat conformation. The asymmetric units of both compounds I and II consist of two independent molecules (A and B). In IIA, three carbon atoms of the cyclohexene ring are disordered over two sets of sites in a 0.670 (11):0.330 (11) occupancy ratio. In the crystal of I, molecules are linked through classical N--H⋯O hydrogen bonds, forming inversion dimers with an R2²(8) ring motif and with their molecular planes parallel to the crystallographic (020) plane. Non-classical C--H⋯O hydrogen-bonding interactions connect the dimers, resulting in a three-dimensional network. In the crystal of II, molecules are linked by C--H⋯N, C--H⋯O and C--H⋯π interactions, forming a three-dimensional network. [ABSTRACT FROM AUTHOR]

In the title compound, C27H33NO5, a 3,3,6,6-tetramethyltetrahydroacridine-1,8-dione ring system carries an ethyl acetate substituent on the acridine N atom and an o-hydroxyphenyl ring on the central methine C atom of the dihydropyridine ring. The benzene ring is inclined to the acridine ring system at an angle of 80.45 (7)° and this conformation is stabilized by an intramolecular O--H…O hydrogen bond between the hydroxy substituent on the benzene ring and one of the carbonyl groups of the acridinedione unit. The ester C=O oxygen atom is disordered over major and minor orientations in a 0.777 (9):0.223 (9) ratio and the terminal--CH3 unit of the ethyl side chain is disordered over two sets of sites in a 0.725 (5): 0.275 (5) ratio. In the crystal, C--H…O hydrogen bonds combine to link the molecules into a three-dimensional network. van der Waals H…H contacts contribute the most to the Hirshfeld surface (66.9%) followed by O…H/H…O (22.1%) contacts associated with weak hydrogen bonds. [ABSTRACT FROM AUTHOR]

The title compound, C21H23F2NO, consists of two fluorophenyl groups and one butyl group equatorially oriented on a piperidine ring, which adopts a chair conformation. The dihedral angle between the mean planes of the phenyl rings is 72.1 (1)°. In the crystal, N--H…O and weak C--H…F interactions, which form R2 [14] motifs, link the molecules into infinite C(6) chains propagating along [001]. Aweak C--H…τ interaction is also observed. A Hirshfeld surface analysis of the crystal structure indicates that the most significant contributions to the crystal packing are from H…H (53.3%), H…C/C…H (19.1%), H…F/ F…H (15.7%) and H…O/O…H (7.7%) contacts. Density functional theory geometry-optimized calculations were compared to the experimentally determined structure in the solid state and used to determine the HOMO-LUMO energy gap and compare it to the UV-vis experimental spectrum. [ABSTRACT FROM AUTHOR]2 [14] motifs, link the molecules into infinite C(6) chains propagating along [001]. Aweak C--H…τ interaction is also observed. A Hirshfeld surface analysis of the crystal structure indicates that the most significant contributions to the crystal packing are from H…H (53.3%), H…C/C…H (19.1%), H…F/ F…H (15.7%) and H…O/O…H (7.7%) contacts. Density functional theory geometry-optimized calculations were compared to the experimentally determined structure in the solid state and used to determine the HOMO-LUMO energy gap and compare it to the UV-vis experimental spectrum. [ABSTRACT FROM AUTHOR]

The title com­pound, C24H24N2O6, consists of ethyl 2-(1,2,3,4-tetra­hydro-2-oxo­quinolin-1-yl)acetate and 4-[(2-eth­oxy-2-oxoeth­yl)(phen­yl)carbomoyl] units, where the oxo­quinoline unit is almost planar and the acetate substituent is nearly perpendicular to its mean plane. In the crystal, C—HOxqnOEthx and C—HPh­yl∙∙∙OCarbx (Oxqn = oxoquinolin, Ethx = eth­oxy, Phyl = phenyl and Carbx = carboxyl­ate) weak hydrogen bonds link the mol­ecules into a three-dimensional network sturucture. A π–π inter­action between the constituent rings of the oxo­quinoline unit, with a centroid–centroid distance of 3.675 (1) Å may further stabilize the structure. Both terminal ethyl groups are disordered over two sets of sites. The ratios of the refined occupanies are 0.821 (8):0.179 (8) and 0.651 (18):0.349 (18). The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H∙∙∙H (53.9%), H∙∙∙O/O∙∙∙H (28.5%) and H∙∙∙C/C∙∙∙H (11.8%) inter­actions. Weak inter­molecular hydrogen-bond inter­actions and van der Waals inter­actions are the dominant inter­actions in the crystal packing. Density functional theory (DFT) geometric optimized structures at the B3LYP/6-311G(d,p) level are com­pared with the experimentally determined mol­ecular structure in the solid state. The HOMO–LUMO mol­ecular orbital behaviour was elucidated to determine the energy gap. [ABSTRACT FROM AUTHOR]

The asymmetric unit of O,O′‐dimethyl [(2,3,4,5,6‐pentafluorophenyl)hydrazinyl]phosphonate, C8H8F5N2O3P, is composed of two symmetry‐independent molecules with significant differences in the orientations of the C6F5 and OMe groups. In the crystal structure, a one‐dimensional assembly is mediated from classical N—H...O hydrogen bonds, which includes R22(8), D(2) and some higher‐order graph‐set motifs. By also considering weak C—H...O=P and C—H...O—C intermolecular interactions, a two‐dimensional network extends along the ab plane. The strengths of the hydrogen bonds were evaluated using quantum chemical calculations with the GAUSSIAN09 software package at the B3LYP/6‐311G(d,p) level of theory. The LP(O) to σ*(NH) and σ*(CH) charge‐transfer interactions were examined according to second‐order perturbation theory in natural bond orbital (NBO) methodology. The hydrogen‐bonded clusters of molecules, including N—H...O and C—H...O interactions, were constructed as input files for the calculations and the strengths of the hydrogen bonds are as follows: N—H...O [R22(8)] > N—H...O [D(2)] > C—H...O. The decomposed fingerprint plots show that the contribution portions of the F...H/H...F contacts in both molecules are the largest. [ABSTRACT FROM AUTHOR]

Three new Cu(II) Schiff base complexes with bidentate N-donor heterocyclic co-ligands, 2,2'-bipyridine (1), 1,10-phenanthroline (2), and 2,9-dimethyl-1,10-phenanthroline (3), were synthesized and characterized by FT-IR and UV-vis spectroscopy. Molecular structures of [C20H21CuN4O](ClO4) (1) and [C24H25CuN4O](ClO4) (3) were characterized by single-crystal X-ray crystallography. The Schiff base ligand is an N2O-type ligand, which is the mono-condensed form of the reaction between 1,3-propanediamine and salicylaldehyde. The antibacterial activities of these complexes were investigated against one gram positive and four gram negative bacteria. Considerable antibacterial activity was obtained against both gram type bacteria. Complexes 2 and 3 with 1,10-phenanthroline and 2,9-dimethyl-1,10-phenanthroline, respectively, showed better antibacterial activity compared to 1 which has the 2,2'-bipyridine co-ligand. [ABSTRACT FROM AUTHOR]

The title compound, C17H18N2O3, is constructed from a benzodiazepine ring system linked to a pendant dihydropyran ring, where the benzene and pendant dihydropyran rings are oriented at a dihedral angle of 15.14 (4)°. Intramolecular N--HDiazp...ODhydp and C--HDiazp...ODhydp (Diazp = diazepine and Dhydp = dihydropyran) hydrogen bonds link the seven-membered diazepine ring to the pendant dihydropyran ring, enclosing S(6) ring motifs. In the crystal, N--HDiazp...ODhydp hydrogen bonds link the molecules into infinite chains along [101]. These chains are further linked via C--HBnz...ODhydp, C--HDhydp...ODhydp and C--HMth..ODhydp (Bnz = benzene and Mth = methyl) hydrogen bonds, forming a three-dimensional network. The observed weak C--HDiazp... ° interaction may further stabilize the structure. Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H...H (51.1%), H...C/C...H (25.3%) and H...O/O...H (20.3%) interactions. Hydrogen bonding and van der Waals interactions are the dominant interactions in the crystal packing. [ABSTRACT FROM AUTHOR]

Structures are reported for eight Schiff bases derived from various salicylaldehydes: five are newly synthesized and re‐investigations are reported for three previously reported structures, leading, in each case, to some revision of previous conclusions. In (E)‐N‐(3,4‐dimethylisoxazol‐5‐yl)‐4‐[(2‐hydroxybenzylidene)amino]benzenesulfonamide, C18H17N3O4S, (I), and (E)‐4‐[(5‐bromo‐2‐hydroxy‐3‐methoxybenzylidene)amino]‐N‐(3,4‐dimethylisoxazol‐5‐yl)benzenesulfonamide. C19H18BrN3O5S, (II), the isoxazole rings adopt different orientations relative to the rest of the molecules, despite the additional substituents in (II) being in the aryl ring remote from the isoxazole unit. The molecules of both (E)‐4‐bromo‐2‐[(2‐hydroxyphenylimino)methyl]‐6‐methoxyphenol, C14H12BrNO3, (III), and (E)‐4‐bromo‐2‐methoxy‐6‐[(2‐methoxyphenylimino)methyl]phenol, C15H14BrNO3, (IV), are both effectively planar; while (III) adopts the phenol–imine constitution, (IV) adopts the keto–amine constitution. (E)‐2‐Methoxy‐6‐[(2‐methoxyphenylimino)methyl]phenol, C15H15NO3, (V), which was determined previously using powder X‐ray data assuming the phenol–imine constitution, has now been refined from single‐crystal X‐ray data, confirming the phenol–imine constitution. In (E)‐3‐benzoyl‐2‐[(5‐fluoro‐2‐hydroxybenzylidene)amino]‐4,5,6,7‐tetrahydrobenzo[b]thiophene, C22H18FNO2S, (VI), the fused carbocyclic ring exhibits conformational disorder; both disorder components, having populations of 0.705 (4) and 0.295 (4), adopt half‐chair conformations. The isostructural (E)‐3‐benzoyl‐2‐[(2‐hydroxybenzylidene)amino)]‐4,5,6,7‐tetrahydrobenzo[b]thiophene, C22H19NO2S, (VII), which was originally reported as having a fully ordered structure [Kaur et al. (2014). Acta Cryst. E70, o476–o477], has been rerefined using the original data set and found to exhibit the same type of disorder as found in (VI), with disordered populations having occupancies of 0.851 (3) and 0.149 (3). The triclinic polymorph of (E)‐[(2‐hydroxyphenylimino)methyl]phenol, C13H11NO2, (VIII), which crystallizes with Z′ = 2 in the space group P , has been described variously as occurring as the keto–amine tautomer [Maciejewska et al. (1999). J. Phys. Org. Chem.12, 875–880] and as the phenol–imine tautomer [Tunç et al. (2009). J. Chem. Crystallogr.39, 672–676]. Rerefinement of this structure using one of the original data sets shows that both of the independent molecules exist in the keto–amine form. In the structures of compounds (I), (VI), (VII) and (VIII), hydrogen bonds generate simple chains, while a chain of rings is formed in (V). Sheets are formed by hydrogen bonds in both (II) and (III), while in (IV), the sheet structure is built from aromatic π–π stacking interactions. [ABSTRACT FROM AUTHOR]

The doping of metal oxides with rare-earth element is an effective way of enhancing the optical properties of ZnO nanoparticles. The ZnO nanoparticles were prepared using co-precipitation method with different concentrations of Eu, constant N doping and characterized through X-ray diffraction, scanning electron microscopy, Raman spectroscopy and UV-visible spectroscopy. The Rietveld refined XRD of ZnO nanoparticles confirms the hexagonal wurtzite structure. The XRD results indicated that crystallite size increases with doping and found in the range of 37–52 nm. Scanning electron microscopy illustrated that ZnO nanoparticles were less agglomerated and the average size of nanoparticles was found to increase from 62 to 90 nm with doping. Raman spectrum also confirmed hexagonal wurtzite arrangement of all samples. The band gap of pristine ZnO nanoparticles was found 3.18 eV as confirmed by UV-visible spectroscopy. The red shift (3.14 eV & 3.16 eV) in band gap was observed at 2 & 3 mol% of Eu, while blue shift (3.20 eV & 3.23 eV) in band gap was observed at 1 & 4 mol% of Eu respectively. This modification in the band gap makes ZnO nanoparticles an appropriate electrode material for dye-sensitized solar cells and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Structural characterization of the compound [Cu(C2H3N)(C23H23N3O)](ClO4)2] or [Cu(C2H3N)(DQMEA)](ClO4)2] [DQMEA = 2-methoxy-N,N-bis(quinolin-2-ylmethyl)ethylamine] {systematic name: (acetonitrile)[2-methoxy-N,N-bis-(quinolin-2-ylmethyl)ethylamine]copper(II) diperchlorate} by single-crystal X-ray diffraction reveals a complex cation with a tetradentate coordination of the DQMEA ligand along with monodentate coordination of a CH3CN ligand to a single Cun center, with two perchlorate anions providing charge balance. The CuII center has a distorted square-pyramidal geometry in which the nitrogen atoms of the DQMEA and CH3CN ligands occupy the equatorial positions, while the oxygen atom of the DQMEA ligand resides in the axial position with an elongated Cu -- O bond. The quinoline ring systems are nearly co-planar in the structure, while the linear CH3CN ligand is tilted significantly below this plane, and the central nitrogen of DQMEA is above it. Within the complex, weak C--H...N hydrogen bonding takes place between the nitrogen of CH3CN and a neighboring quinolyl group. The perchlorate ions are disordered within the structure, but undergo a number of weak intermolecular C -- H...O hydrogen-bonding interactions. Additional weak εstacking interactions between the quinolyl groups of neighboring complexes further stabilize the crystal packing. [ABSTRACT FROM AUTHOR]

Structural analysis of (acetato-κ2O,O′)(methanol-κO)[tris­(pyridin-2-ylmeth­yl)amine-κ4N,N′,N′′,N′′′]manganese(II) tetraphenyl­borate, [Mn(C2H3O2)(C18H18N4)(CH3OH)](C24H20B) or [Mn(TMPA)(Ac)(CH3OH)]BPh4 [TMPA = tris­(pyridin-2-ylmeth­yl)amine, Ac = acetate, BPh4 = tetra­phenyl­borate] by single-crystal X-ray diffraction reveals a complex cation with tetra­dentate coordination of the tripodal TMPA ligand, bidentate coordination of the Ac ligand and monodentate coordination of the methanol ligand to a single MnII center, balanced in charge by the presence of a tetra­phenyl­borate anion. The MnII complex has a distorted penta­gonal–bipyramidal geometry, in which the central amine nitro­gen and two pyridyl N atoms of the TMPA ligand, and two oxygen atoms of the acetate ligand occupy positions in the penta­gonal plane, while the third pyridyl nitro­gen of TMPA and the oxygen from the methanol ligand occupy the axial positions. Within the complex, the acetate O atoms participate in weak C—HO hydrogen-bonding inter­actions with neighboring pyridyl moieties. In the crystal, complexes form dimers by pairs of O—HO hydrogen bonds between the coordinated methanol of one complex and an acetate oxygen of the other, and weak π-stacking inter­actions between pyridine rings. Separate dimers then undergo additional π-stacking inter­actions between the pyridine rings of one moiety and either the pyridine or phenyl rings of another moiety that further stabilize the crystal. [ABSTRACT FROM AUTHOR]

The syntheses and crystal structures of 3-(2-chloro­eth­yl)-r-2,c-6-di­phenyl­piperidin-4-one, C19H20ClNO, (I), and 3-(2-chloro­eth­yl)-r-2,c-6-bis­(4-fluoro­phenyl)piperidin-4-one, C19H18ClF2NO, (II), are described. The piperidone ring adopts a chair conformation in (I), whereas a slightly distorted chair conformation is formed in (II). The dihedral angle between the mean plane of the phenyl rings is 59.1 (1)° in (I) and 76.1 (1)° in (II). The crystal packing features weak inter­molecular N—H⋯O hydrogen bonds in each structure. [ABSTRACT FROM AUTHOR]

The syntheses and crystal structure of 3-chloro-3-methyl-r-2,c-6-diphenylpiperidin-4-one, C18H18ClNO, (I), 3-chloro-3-methyl-r-2,c-6-di-p-tolylpiperidin-4-one, C20H22ClNO, (II), and 3-chloro-3-methyl-r-2,c-6-bis(4-chlorophenyl)piperidin-4-one, C18H16Cl3NO, (III), are described. In each structure, the piperidine ring adopts a chair conformation and dihedral angles between the mean planes of the phenyl rings are 58.4 (2), 73.5 (5) and 78.6 (2)° in (I), (II) and (III), respectively. In the crystals, molecules are linked into C(6) chains by weak N-H···O hydrogen bonds and C-H···π interactions are also observed. [ABSTRACT FROM AUTHOR]

The lattice of 5,7,12,14-tetrahydro-5,14:7,12-bis([1,2]benzeno)pentacene-6,13-dione, C34H20O2, at 173 K has triclinic (P...) symmetry and crystallizes with four independent half-molecules in the asymmetric unit. Each molecule is generated from a C17H10O substructure through an inversion center at the centroid of the central quinone ring, generating a wide H-shaped molecule, with a dihedral angle between the mean planes of the terminal benzene rings in each of the two symmetry-related pairs over the four molecules of 68.6 (1) (A), 65.5 (4) (B), 62.3 (9) (C), and 65.8 (8)° (D), an average of 65.6 (1)°. This compound has applications in gas-separation membranes constructed from polymers of intrinsic microporosity (PIM). The title compound is a product of a double Diels-Alder reaction between anthracene and p-benzoquinone followed by dehydrogenation. It has also been characterized by cyclic voltammetry and rotating disc electrode polarography, FT-IR, high resolution mass spectrometry, elemental analysis, and ¹H NMR. [ABSTRACT FROM AUTHOR]

Hydrazone derivatives exhibit a wide range of biological activities, while pyrazolo[3,4- b]quinoline derivatives, on the other hand, exhibit both antimicrobial and antiviral activity, so that all new derivatives in these chemical classes are potentially of value. Dry grinding of a mixture of 2-chloroquinoline-3-carbaldehyde and 4-methylphenylhydrazinium chloride gives ( E)-1-[(2-chloroquinolin-3-yl)methylidene]-2-(4-methylphenyl)hydrazine, C17H14ClN3, (I), while the same regents in methanol in the presence of sodium cyanoborohydride give 1-(4-methylphenyl)-4,9-dihydro-1 H-pyrazolo[3,4- b]quinoline, C17H15N3, (II). The reactions between phenylhydrazinium chloride and either 2-chloroquinoline-3-carbaldehyde or 2-chloro-6-methylquinoline-3-carbaldehyde give, respectively, 1-phenyl-1 H-pyrazolo[3,4- b]quinoline, C16H11N3, (III), which crystallizes in the space group Pbcn as a nonmerohedral twin having Z′ = 3, or 6-methyl-1-phenyl-1 H-pyrazolo[3,4- b]quinoline, C17H13N3, (IV), which crystallizes in the space group R. The molecules of compound (I) are linked into sheets by a combination of N-H...N and C-H...π(arene) hydrogen bonds, and the molecules of compound (II) are linked by a combination of N-H...N and C-H...π(arene) hydrogen bonds to form a chain of rings. In the structure of compound (III), one of the three independent molecules forms chains generated by C-H...π(arene) hydrogen bonds, with a second type of molecule linked to the chains by a second C-H...π(arene) hydrogen bond and the third type of molecule linked to the chain by multiple π-π stacking interactions. A single C-H...π(arene) hydrogen bond links the molecules of compound (IV) into cyclic centrosymmetric hexamers having ( S6) symmetry, which are themselves linked into a three-dimensional array by π-π stacking interactions. [ABSTRACT FROM AUTHOR]

The structures of four halogenated N,2-diarylacetamides are reported and compared with a range of analogues. N-(4-Chloro-3-methylphenyl)-2-phenylacetamide, C15H14ClNO, (I), and N-(4-bromo-3-methylphenyl)-2-phenylacetamide, C15H14BrNO, (II), are isostructural in the space group P. The molecules of (I) and (II) are linked into chains of rings by a combination of N-H...O and C-H...π(arene) hydrogen bonds. The molecules of N-(4-chloro-3-methylphenyl)-2-(2,4-dichlorophenyl)acetamide, C15H12Cl3NO, (III), and N-(4-bromo-3-methylphenyl)-2-(2-chlorophenyl)acetamide, C15H13BrClNO, (IV), are linked into simple C(4) chains by N-H...O hydrogen bonds, but significant C-H...π(arene) interactions are absent. The N-aryl groups in compounds (III) and (IV) adopt a different orientation, by ca 180°, from that of the corresponding groups in compounds (I) and (II), but otherwise the conformations of (I)-(IV) are very similar. Comparisons are drawn between compounds (I) and (IV) and a range of analogues of the type R1CH2CONH R2, where R2 represents a halogenated aryl ring and R1 represents either another halogenated aryl ring or a naphthalen-1-yl unit. [ABSTRACT FROM AUTHOR]

Four imidazo[2,1- b][1,3,4]thiadiazoles containing a simply-substituted 6-aryl group have been synthesized by reaction of 2-amino-1,3,4-thiadiazoles with bromoacetylarenes using microwave irradiation and brief reaction times. 6-(2-Chlorophenyl)imidazo[2,1- b][1,3,4]thiadiazole, C10H6ClN3S, (I), 6-(2-chlorophenyl)-2-methylimidazo[2,1- b][1,3,4]thiadiazole, C11H8ClN3S, (II), 6-(3,4-dichlorophenyl)imidazo[2,1- b][1,3,4]thiadiazole, C10H5Cl2N3S, (III), and 6-(4-fluoro-3-methoxyphenyl)-2-methylimidazo[2,1- b][1,3,4]thiadiazole, C12H10FN3OS, (IV), crystallize with Z′ values of 2, 1, 1 and 2 respectively. The molecular skeletons are all nearly planar and the dihedral angles between the imidazole and aryl rings are 1.51 (8) and 7.28 (8)° in (I), 9.65 (7)° in (II), 10.44 (8)° in (III), and 1.05 (8) and 7.21 (8)° in (IV). The molecules in (I) are linked by three independent C-H...N hydrogen bonds to form ribbons containing alternating R22(8) and R44(18) rings, and these ribbons are linked into a three-dimensional array by three independent π-stacking interactions. Both (II) and (III) contain centrosymmetric dimers formed by π-stacking interactions but hydrogen bonds are absent, and the molecules of (IV) are linked into centrosymmetric R22(8) dimers by C-H...N hydrogen bonds. Comparisons are made with a number of related compounds. [ABSTRACT FROM AUTHOR]

The structures of two salts of flunarizine, namely 1-bis[(4-fluorophenyl)methyl]-4-[(2 E)-3-phenylprop-2-en-1-yl]piperazine, C26H26F2N2, are reported. In flunarizinium nicotinate {systematic name: 4-bis[(4-fluorophenyl)methyl]-1-[(2 E)-3-phenylprop-2-en-1-yl]piperazin-1-ium pyridine-3-carboxylate}, C26H27F2N2+·C6H4NO2−, (I), the two ionic components are linked by a short charge-assisted N-H...O hydrogen bond. The ion pairs are linked into a three-dimensional framework structure by three independent C-H...O hydrogen bonds, augmented by C-H...π(arene) hydrogen bonds and an aromatic π-π stacking interaction. In flunarizinediium bis(4-toluenesulfonate) dihydrate {systematic name: 1-[bis(4-fluorophenyl)methyl]-4-[(2 E)-3-phenylprop-2-en-1-yl]piperazine-1,4-diium bis(4-methylbenzenesulfonate) dihydrate}, C26H28F2N22+·2C7H7O3S−·2H2O, (II), one of the anions is disordered over two sites with occupancies of 0.832 (6) and 0.168 (6). The five independent components are linked into ribbons by two independent N-H...O hydrogen bonds and four independent O-H...O hydrogen bonds, and these ribbons are linked to form a three-dimensional framework by two independent C-H...O hydrogen bonds, but C-H...π(arene) hydrogen bonds and aromatic π-π stacking interactions are absent from the structure of (II). Comparisons are made with some related structures. [ABSTRACT FROM AUTHOR]

Abstract: The FT-IR, FT-Raman spectra and XRD of 4′-methylbiphenyl-2-carbonitrile were recorded and analyzed. The frequencies were computed at various density functional theoretical levels using Gaussian09 software package. The data obtained from theoretical calculations were used to assign vibrational bands obtained in infrared and Raman spectra of the studied molecule. Potential energy distribution of the normal modes of vibrations were done using GAR2PED program. The geometrical parameters of the title compound are in agreement with XRD crystal structure data. The first hyperpolarizability is comparable with the reported values of similar derivatives and is an attractive object for future studies of non linear optics. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using NBO analysis. According to XRD data, the dihedral angles between the mean planes of the two benzene rings is 44.7° and the crystal packing is stabilized by weak intermolecular π–π stacking interactions. [Copyright &y& Elsevier]

The article discusses the crystal structure of desvenlafaxinium 3,5-dinitrobenzoate 3,5-dinitrobenzoic acid monohydrate, C30H35N5O15. Topics discussed include the source of material, experimental data, and the study on the compound which is considered as the first non-hormonal based treatment for menopause. Also provided is a table which shows information on data collection.

The article discusses the crystal structure of desvenlafaxinium 3,5-dinitrobenzoate 3,5-dinitrobenzoic acid monohydrate, C30H35N5O15. Topics discussed include the source of material, experimental data, and the study on the compound which is considered as the first non-hormonal based treatment for menopause. Also provided is a table which shows information on data collection.

A novel derivative of pyrimidine containing the 1,2,4-triazolo[1,5-a]pyrimidine ring has been synthesized by means of a condensation reaction of 3-amino-1,2,4-triazole with 4-hyroxy-6-methyl-pyran-2-one. The resulting structure of 2-(4-vinylbenzyl)-2-(5-methyl-[1,2,4]triazolo[1,5-a]pyrimidin-7-yl)-3-(4-vinylphenyl)propanoate, C 10 H 12 N4O 2 , (3), has been characterized by X-ray single crystal diffraction (XRD) and a variety of selected spectroscopic techniques (1H NMR, 13C and IR). The geometrical parameters and spectral data of 3 were also compared with those of a DFT geometry optimization and molecular orbital calculation utilizing the B3LYP/6-31 + G(d,p) level of theory in PCM. The intermolecular contacts in 3 were then investigated by analysis of its Hirshfeld surface along with ESP maps. The antibacterial activity of 3 against Gram positive and Gram-negative microbial strains such as Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa were evaluated with results showing antibacterial activity of 3 with respect to a MIC reference. Image 1 • Synthesis of a novel derivative of 1,2,4-triazolo[1,5-a]pyrimidine derivative. • 3D molecular structure is characterized using x-Ray and spectroscopic techniques. • Good correlations are obtained between the spectra and Xx-ray data with the predicted ones. • The synthesized compound shows significant antibacterial activity. [ABSTRACT FROM AUTHOR]

Abstract A series of eight biologically active N , N ′-disubstituted thiocarbamide compounds (1 – 8) have been prepared from thiophene-2-carbonyl isothiocyanate and various substituted aromatic primary amines (2,4-dichlorophenyl aniline, 4-chloro-3-nitrophenyl aniline, 4-methoxycarbonylphenyl aniline, 3-methoxycarbonylphenyl aniline, 2-methoxycarbonylphenyl aniline, 4-methoxyphenyl aniline, 2-methoxyphenyl aniline and 2-nitrophenyl aniline). Their structures were confirmed by elemental analyses, various spectroscopic techniques ((FT–IR, 1H and 13C NMR) and single crystal X-ray analysis of compound (1). In the molecular structure of compound (1) twisted confirmation of the carbonyl and thiocarbonyl group across C N bond of thiocarbamide moiety and an offset face-to-face π – π stacking between two thiophene and two benzene ring of two molecules is observed. In vitro cytotoxicity assay of all the above compounds and five more (9–13) were carried out using seven human cancer cell lines; cervical (2008 and C13*), colorectal (HT29 and HCT116) and ovarian carcinoma (A2780, A2780/CP and IGROV-1). The results revealed that compounds 1 , 11 , 12 and 13 displayed promising inhibitory activity against all the cell lines tested. Graphical abstract In the present study, a series of biologically active N, N′–disubstituted thiocarbamide compounds (1–8) have been synthesized and characterized by some spectroscopic (FT-IR, 1H and 13C NMR, UV–Visible) techniques. The molecular structure of compound 1 was determined by single crystal X-ray diffraction analysis. All the synthesized compounds (1–8) and five more (9–13) were screened for their in vitro cytotoxicity activities. Image 1 Highlights • SCXRD of compound 1 and various spectroscopic techniques were used to establish the structure of the compounds. • The presence of intramolecular hydrogen bond (N H⋯O C) compels planarity of the molecule. • The compounds were screened for their In vitro cytotoxic activity against seven human cancer cell lines. • The compounds screened for their cytotoxic activity in seven human cell lines exhibited promising anticancer activity. • All the compounds except 5 , 9 and 10 displayed stronger inhibitory activity than standard drug (5-FU) and HT29 cell line. [ABSTRACT FROM AUTHOR]

Abstract A new asymmetric bidentate Schiff-base molecule 4-Chloro-2-(5,6-dihydro-benzo[4,5]imidazo[1,2- c ]quinazolin-6-yl)-phenol (HL), has been synthesized and characterized using physicochemical and spectroscopic techniques, single crystal X-ray diffraction and Hirshfeld surface analysis. Crystal structure analysis reveals that the compound crystallized in the orthorhombic system in the Pbca space group. The in vitro interactions of the synthesized compound, with bovine serum albumin was thoroughly investigated using UV–Vis absorption in combination with fluorescence quenching techniques, and these methods were used to determine the binding parameters also the mechanism of interaction behind the new compound HL bound to BSA. Values of the binding constants (K b) were about ∼105 M−1 signifying a moderate interaction between HL and BSA making the protein suitable for transportation and delivery of the compound. Thermodynamic parameters also revealed binding through weak van der Waals forces and hydrogen bonding interactions of HL to BSA. The results obtained from docking studies were consistent and complemented those derived from other experimental studies. Graphical abstract Image 1 Highlights • A new Schiff base molecule (HL) has been synthesized in good yield. • The compound (HL) is characterized by X-ray Crystallography, Hirshfeld surface analysis and spectroscopic methods. • Bovine Serum Albumin interaction studies with Imine base (HL) have been performed by spectroscopic techniques. • A molecular docking study also helps to unravel the binding nature of HL with bovine serum albumin. [ABSTRACT FROM AUTHOR]

A new imine-based molecule 2-((E)-(6-fluorobenzo[ d ]thiazol-2-ylimino) methyl)-4-chlorophenol (FBt) was synthesized by microwave and conventional method. It was structurally characterized by spectral techniques (NMR, FT-IR, LC-MS and electronic absorption), elemental analysis and single-crystal X-ray diffraction methods. Hirshfeld surface analysis was employed to ensure the existence of intermolecular interactions in FBt structure. A preliminary in vitro susceptibility test against two pathogenic fungi with respect to standard has shown that the ligand is proved to be a potent antifungal agent. Since the carrying of a drug by BSA may effect on its structure and action, the investigation on the interaction between model protein BSA and FBt was carried out by employing UV–Vis and fluorescence spectroscopy. The characteristics of the binding, i.e., binding constant, number of binding sites, and nature of binding were determined. Besides, the Förster's parameters associated with the binding process were calculated. Molecular docking was also carried on interaction study of the FBt with BSA. [ABSTRACT FROM AUTHOR]

Highlights: [•] New series of 2-chloroquinolin-3-yl ester derivatives were synthesized. [•] Chemical structures of the compounds were characterized by 1H NMR, 13C NMR, LCMS spectral analysis and elemental analysis. [•] X-ray crystallographic study of 6a and 6e were carried out. [•] In vitro antimicrobial and ABTS radical-scavenging activity screening were carried out. [•] The docking studies were carried out. [ABSTRACT FROM AUTHOR]

Four new compounds N -(4-nitrophenyl)- N '-(isobutoxycarbonyl) thiocarbamide (1), N -(2, 4-nitrophenyl)- N '-(isobutoxycarbonyl) thiocarbamide (2), N -(4-nitrophenyl)- N '-(ethoxycarbonyl) thiocarbamide (3) and N -(2-Chloro- 4-nitrophenyl)- N '-(ethoxycarbonyl) thiocarbamide (4) were prepared and their structures confirmed by using various spectroscopic (FT-IR, UV–Visible, 1H and 13C NMR) and single crystal X-ray studies of 1 and 3. The presence of intramolecular (N–H⋯O C) hydrogen bond in the crystal structure of both the compounds causes planarity of carbonyl thiocarbamide unit and trans orientation of C O and C S group. The intermolecular contacts (C–H⋯S, C–H⋯O and N–H⋯S) present in crystal structures have been examined by Hirshfeld surface analysis and their associated 2D fingerprint plots. All the compounds were assessed for their in vitro cytotoxic properties against a panel of seven human cancer cells such as cervical carcinoma (2008, C13*), colorectal (HT29 and HCT116) and ovarian carcinoma (A2780, A2780/CP and IGROV-1). Among them, compounds 2 and 4 exhibited better activity than 1 and 3 against all the cell lines tested. A series of four N, N′–disubstituted thiocarbamide derivatives (1–4) were synthesized for their in-vitro anticancer activity evaluation. Significant activity was found in compounds 2 and 4. All compounds were characterized well through different spectroscopic techniques; however, structural evaluation of compounds 1 and 3 was done through single crystal X-ray diffraction data. Further quantitative analysis of noncovalent interactions for compounds 1 and 3 was done by Hirshfeld surfaces analysis which showed that O⋯H and S⋯H interactions are playing a major role in stabilizing the crystal lattice. Image 1 • Single crystal X-ray analysis of compounds 1, 3 and various spectroscopic techniques were used to establish the structure of the compounds. • The presence of intramolecular hydrogen bond (N─H⋯O C) compels planarity of the molecule. • Hirshfeld surfaces analysis of compounds 1, 3 were performed to understand hydrogen bonding and other weak interactions. • The compounds were screened for their In vitro cytotoxic activity against seven human cancer cell lines. • The compounds screened for their cytotoxic activity in seven human cancer cell lines exhibited promising anticancer activity. [ABSTRACT FROM AUTHOR]