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Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 and SAINT (Bruker, 2004); data reduction: SAINT and XPREP (Bruker, 2004); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine... more
Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 and SAINT (Bruker, 2004); data reduction: SAINT and XPREP (Bruker, 2004); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97 and PLATON.
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The crystal structures of two fused pyridine derivatives viz Ethyl 3-amino-6-phenyl-4-tolylfuro[2,3-b]pyridine-2-carboxylate (I) and Ethyl 3-amino-6-phenyl-4-tolylthieno[2,3-b] pyridine-2-carboxylate (II) were optimized by semi-empirical... more
The crystal structures of two fused pyridine derivatives viz Ethyl 3-amino-6-phenyl-4-tolylfuro[2,3-b]pyridine-2-carboxylate (I) and Ethyl 3-amino-6-phenyl-4-tolylthieno[2,3-b] pyridine-2-carboxylate (II) were optimized by semi-empirical methods using MOPAC2009 program. The geometries optimized for both the structures from Austin Model 1 (AM1) and Parametrization Model 6 (PM6) describe the conformational discrepancy and crystal packing effects. The parametric molecular electrostatic potential (PMEP) calculated by AM1 semi-empirical method describe the involvement of nitrogen and oxygen atoms in the crystal packing interactions in both the structures. The frontier molecular orbitals highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) indicate the intramolecular charge transfer interactions. The HOMED indices computed for the phenyl rings in the structures describe the p-electron delocalization. The linear regression analysis shows good correlation between experimental and theoretical structures.
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The crystal structures of two fused pyridine derivatives viz Ethyl 3-amino-6-phenyl-4-tolylfuro[2,3-b]pyridine-2-carboxylate (I) and Ethyl 3-amino-6-phenyl-4-tolylthieno[2,3-b] pyridine-2-carboxylate (II) were optimized by semi-empirical... more
The crystal structures of two fused pyridine derivatives viz Ethyl 3-amino-6-phenyl-4-tolylfuro[2,3-b]pyridine-2-carboxylate (I) and Ethyl 3-amino-6-phenyl-4-tolylthieno[2,3-b] pyridine-2-carboxylate (II) were optimized by semi-empirical methods using MOPAC2009 program. The geometries optimized for both the structures from Austin Model 1 (AM1) and Parametrization Model 6 (PM6) describe the conformational discrepancy and crystal packing effects. The parametric molecular electrostatic potential (PMEP) calculated by AM1 semi-empirical method describe the involvement of nitrogen and oxygen atoms in the crystal packing interactions in both the structures. The frontier molecular orbitals highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) indicate the intramolecular charge transfer interactions. The HOMED indices computed for the phenyl rings in the structures describe the p-electron delocalization. The linear regression analysis shows good correlation...
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In the title compound. C(10)H(9)Cl(2)NO(2), the acetamide residue is twisted out of the phenyl ring plane by 25.40 (9)degrees. An intramolecular C-H center dot center dot center dot O close contact is observed. The N atom of the... more
In the title compound. C(10)H(9)Cl(2)NO(2), the acetamide residue is twisted out of the phenyl ring plane by 25.40 (9)degrees. An intramolecular C-H center dot center dot center dot O close contact is observed. The N atom of the butanamide unit forms an intermolecular N-H center dot center dot center dot O hydrogen bond with the symmetry-related carbonyl O atom, interlinking molecules into a C(4) chain along [100]. Additional C-H center dot center dot center dot O intermolecular interactions and Cl center dot center dot center dot Cl contacts [3.4364 (8) angstrom] contribute to the stability of the crystal packing.
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Synthesis, characterisation, docking analysis and biological evaluation of α,α′-bis(p-dimethylaminobenzylidene)-γ-methylcyclohexanone α,α′-bis(p-Dimethylaminobenzylidene)-γ-methylcyclohexanone (BMABMC) C 25 H 30 ON 2, has been synthesised... more
Synthesis, characterisation, docking analysis and biological evaluation of α,α′-bis(p-dimethylaminobenzylidene)-γ-methylcyclohexanone α,α′-bis(p-Dimethylaminobenzylidene)-γ-methylcyclohexanone (BMABMC) C 25 H 30 ON 2, has been synthesised and characterised by elemental analysis, 1 H and 13 C NMR, mass spectroscopic techniques and X-ray diffraction (XRD) studies. The single crystal XRD studies of the title compound reveals the presence of C–H ... O intermolecular hydrogen bonding interactions linking inversion-related molecules into a dimer forming a ring of graph set R 2 2 (22). The antibacterial activitiy of the compound has been screened in vitro against the organisms. To evaluate the inhibition of HIV-1 integrase activity, molecular docking was performed and the study reveals a hydrophobic interaction with the catalytic core residues showing moderate inhibitory activity on HIV-1 integrase. The semi-empirical quantum chemical calculations were also performed using MOPAC2009 (PM3) ...
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The crystal structure of the title molecule has been analyzed with the help of AM1 semi-empirical calculations to explain the crystal packing effect and the results were compared with earlier DFT analysis. The electric dipole moment ()... more
The crystal structure of the title molecule has been analyzed with the help of AM1 semi-empirical calculations to explain the crystal packing effect and the results were compared with earlier DFT analysis. The electric dipole moment () and static first and second order hyperpolarizabilities ( and ) have been computed using Time Dependent Hartree Fock (TDHF) method incorporated in MOPAC2009 program to inspect the microscopic non-linear optical behaviour of the title compound. This is in good agreement with the experimentally measured second harmonic generation efficiency of the compound which is 0.36 and 4.17 times to those of urea and KDP respectively, hence it suggests the non-linear optical behaviour of the material. The intramolecular charge transfer interactions result during the HOMO-LUMO transitions observed from the calculated energy values.
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This paper represents a systematic theoretical study on the variation of non-linear optical (NLO) properties with the substituents at different positions of phenyl ring of acetanilides. The semi-empirical quantum chemical calculations on... more
This paper represents a systematic theoretical study on the variation of non-linear optical (NLO) properties with the substituents at different positions of phenyl ring of acetanilides. The semi-empirical quantum chemical calculations on this class of compounds were used to compare their second harmonic generation (SHG) efficiency on the basis of optimized geometries, the dipole moment () and first order hyperpolarizability (). Out of different substituents namely methyl, hydroxyl , nitroxide and chlorides, the nitroxide and amino substituents have significant non-linear behaviour due to comparatively large value of dipole moment () with significant first order hyper polarizability (). The role of crystal packing interactions and frontier molecular orbitals on NLO properties are discussed herein. The prediction of NLO properties from theoretical results are in good agreement with some of experimentally observed results for SHG efficiency.
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The zwitter-ion derivative, 2-[(2-hydroxyphenyl) -iminomethyl] phenyl (2HPIMP), C11 H13 NO2 has two independent molecules per asymmetric unit with almost similar conformation and mutual orthogonal orientations [dihedral angle =... more
The zwitter-ion derivative, 2-[(2-hydroxyphenyl) -iminomethyl] phenyl (2HPIMP), C11 H13 NO2 has two independent molecules per asymmetric unit with almost similar conformation and mutual orthogonal orientations [dihedral angle = 83.77(4)°]. The conformational difference between geometrically optimized structure from semi-empirical method and the experimental structure demonstrated that, the short intra H…H contacts, intra and intermolecular hydrogen bonds are instrumental in stabilizing the structure in the solid state. The intermolecular charge transfer interaction due to an electron transition from highest occupied molecular orbital (HOMO) to lowest unoccupied molecular orbital (LUMO) caused a cloud of charges to move from the atoms of one molecule to another. The molecule exhibited an effective antibacterial activity against S. aureus and moderate action against E. coli and S. Pyogenus as compared to a standard reference drug, Ampicillin
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The crystal structure of N-[2,4,5-Trichlorophenyl] acetamide is optimized through semi-empirical method by Austin Model 1 (AM1) together with restricted Hartree-Fock closed shell wave function to describe the influence of interactions on... more
The crystal structure of N-[2,4,5-Trichlorophenyl] acetamide is optimized through semi-empirical method by Austin Model 1 (AM1) together with restricted Hartree-Fock closed shell wave function to describe the influence of interactions on crystal packing using MOPAC2009 program. The electric dipole moment (μ)and molecular hyperpolarizabilities (β and γ)are computedbytime dependent Hartree Fock (TDHF) method to inspect the non-linear optical behaviour of the material. The UV-VIS spectral study of material in 300-1100 nm wavelength range shows a wide transparency window which is the key requirement for the non-linear optical (NLO) property of the material. The experimentally measured value of second harmonic generation efficiency is 0.8 times to that of reference material potassium dihydrogen phosphate (KDP). The intramolecular charge transfer interaction results during the HOMO-LUMO transition observed from molecular orbital calculations.
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The crystal structure of the title compound, C(20)H(18)N(2)O, reveals a distorted half-chair conformation of the central tetrahydropyridine (THP) ring, with the cyano- and adjacent phenyl-substituted C atoms displaced by 0.329 (1) and... more
The crystal structure of the title compound, C(20)H(18)N(2)O, reveals a distorted half-chair conformation of the central tetrahydropyridine (THP) ring, with the cyano- and adjacent phenyl-substituted C atoms displaced by 0.329 (1) and -0.315 (1) A, respectively, from the THP best plane. Steric interactions force the phenyl rings out of the THP plane by 49.21 (9) and 65.76 (5). The cyano moiety is coplanar with the THP plane.
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ABSTRACT In the title compound, C23H19ClN2O3S, the central pyrimidine ring is significantly puckered, assuming an intermediate conformation between an envelope and a screw-boat form. Short intermolecular C—H⋯O, C—H⋯π and π–π stacking... more
ABSTRACT In the title compound, C23H19ClN2O3S, the central pyrimidine ring is significantly puckered, assuming an intermediate conformation between an envelope and a screw-boat form. Short intermolecular C—H⋯O, C—H⋯π and π–π stacking interactions contribute to the stability of the crystal packing.
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The crystal structure analysis of the biologically-relevant title compound (
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The title Schiff base compound, C14H10Cl2N2O, features an E configuration about each of the C=N imine bonds. Overall, the molecule is approximately planar with the dihedral angle between the central C2N2 residue (r.m.s. deviation =... more
The title Schiff base compound, C14H10Cl2N2O, features an E configuration about each of the C=N imine bonds. Overall, the molecule is approximately planar with the dihedral angle between the central C2N2 residue (r.m.s. deviation = 0.0371 Å) and the peripheral hydroxybenzene and chlorobenzene rings being 4.9 (3) and 7.5 (3)°, respectively. Nevertheless, a small twist is evident about the central N—N bond [the C—N—N—C torsion angle = −172.7 (2)°]. An intramolecular hydroxy-O—H...N(imine) hydrogen bond closes an S(6) loop. In the crystal, π–π stacking interactions between hydroxy- and chlorobenzene rings [inter-centroid separation = 3.6939 (13) Å] lead to a helical supramolecular chain propagating along the b-axis direction; the chains pack without directional interactions between them. The calculated Hirshfeld surfaces point to the importance of H...H and Cl...H/H...Cl contacts to the overall surface, each contributing approximately 29% of all contacts. However, of these only Cl...H ...
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The crystal and molecular structures of the one-dimensional coordination polymer [Zn(S2COEt)2(4LH2)]n(1) and binuclear [Zn(S2COCy)2]2(4LH2) (2) are described, where4LH2is N,N′-bis(pyridin-4-ylmethyl)ethanediamide. In1, the... more
The crystal and molecular structures of the one-dimensional coordination polymer [Zn(S2COEt)2(4LH2)]n(1) and binuclear [Zn(S2COCy)2]2(4LH2) (2) are described, where4LH2is N,N′-bis(pyridin-4-ylmethyl)ethanediamide. In1, the Zn(S2COEt)2entities are linked by bidentate bridging4LH2ligands through the pyridyl-N atoms to generate a twisted supramolecular chain. As a result of monodentate xanthate ligands, the N2S4donor set defines a distorted tetrahedral coordination geometry and, crucially, allows the participation of the non-coordinating sulfur atoms in supramolecular association. Thus, in the crystal amide-N–H···O(amide) and amide-N–H···S(thione) hydrogen bonds link chains into a three-dimensional architecture. The substitution of the ethyl group in the xanthate ligand with a cyclohexyl group results in very different structural outcomes. In2, a binuclear molecule is observed with the coordination geometry for zinc being defined by chelating xanthate ligands and a pyridyl-N atom with ...
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The di-substituted acetylene residue in the title compound, C11H11NO3, is capped at either end by di-methylhydroxy and 4-nitrobenzene groups; the nitro substituent is close to co-planar with the ring to which it is attached [dihedral... more
The di-substituted acetylene residue in the title compound, C11H11NO3, is capped at either end by di-methylhydroxy and 4-nitrobenzene groups; the nitro substituent is close to co-planar with the ring to which it is attached [dihedral angle = 9.4 (3)°]. The most prominent feature of the molecular packing is the formation, via hydroxy-O—H...O(hydroxy) hydrogen bonds, of hexameric clusters about a site of symmetry \overline{3}. The aggregates are sustained by 12-membered {...OH}6 synthons and have the shape of a flattened chair. The clusters are connected into a three-dimensional architecture by benzene-C—H...O(nitro) interactions, involving both nitro-O atoms. The aforementioned interactions are readily identified in the calculated Hirshfeld surface. Computational chemistry indicates there is a significant energy, primarily electrostatic in nature, associated with the hydroxy-O—H...O(hydroxy) hydrogen bonds. Dispersion forces are more important in the other identified but, weaker inte...
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The title compound, C16H18N2O3, is constructed about a central oxopyridazinyl ring (r.m.s. deviation = 0.0047 Å), which is connected to an ethylacetate group at the N atom closest to the carbonyl group, and benzyl and methyl groups second... more
The title compound, C16H18N2O3, is constructed about a central oxopyridazinyl ring (r.m.s. deviation = 0.0047 Å), which is connected to an ethylacetate group at the N atom closest to the carbonyl group, and benzyl and methyl groups second furthest and furthest from the carbonyl group, respectively. An approximately orthogonal relationship exists between the oxopyridazinyl ring and the best plane through the ethylacetate group [dihedral angle = 77.48 (3)°]; the latter lies to one side of the central plane [the Nr—Nr—Cm—Cc (r = ring, m = methylene, c = carbonyl) torsion angle being 104.34 (9)°]. In the crystal, both H atoms of the N-bound methylene group form methylene-C—H...O(ring carbonyl) or N(pyridazinyl) interactions, resulting in the formation of a supramolecular tape along the a-axis direction. The tapes are assembled into a three-dimensional architecture by methyl- and phenyl-C—H...O(ring carbonyl) and phenyl-C—H...O(ester carbonyl) interactions. The analysis of the calculated...