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Item Synthesis, characterization and nonlinear optical properties of 2-[(E)-2-(4-ethoxyphenyl)ethenyl]-1-methylquinolinium 4-substitutedbenzenesulfonate compounds(2010) Ruanwas, P.; Kobkeatthawin, T.; Chantrapromma, S.; Fun, H.-K.; Philip, R.; Smijesh, N.; Padaki, M.; Isloor, A.M.In the present investigation, 2-[(E)-2-(4-ethoxyphenyl)ethenyl]-1-methylquinolinium 4-substituted benzenesulfonate (X = CH3 (1), X = OCH3 (2), X = Cl (3), X = Br (4)) have been synthesized and characterized by 1H NMR, UV-Vis and FT-IR spectroscopy methods. In addition compound 3 was also characterized by single crystal X-ray diffraction (XRD) and found that it crystallized out in the monoclinic space group P21 with cell parameters, a = 9.8072(9) , b = 6.4848(5) , c = 19.4405(16) , ? = 90 , ? = 103.421(5) , ? = 90 , z = 2 and V = 1202.61(17) 3. The nonlinear optical absorption of the samples has been studied at 532 nm using 5 ns laser pulses, employing the open-aperture z-scan technique. It is found that some of the samples are potential candidates for optical limiting applications. 2009 Elsevier B.V. All rights reserved.Item Synthesis and biological evaluation of aminoketones(2010) Sankappa, Rai, U.; Isloor, A.M.; Shetty, P.; Isloor, N.; Malladi, S.; Fun, H.-K.A three-component Mannich reaction of different ketones with aromatic aldehydes and different amines in microwave irradiation under solvent free condition afforded corresponding ?-amino carbonyl compounds in excellent yields. This method proved as a novel and improved modification of the reported three-component Mannich reaction in terms of milder reaction conditions, reaction times, clean reaction profiles, very small quantity of catalyst and simple workup procedure. Newly synthesized ?-aminoketones were characterized by spectral studies. Structure of compound 4a was also confirmed by single-crystal X-ray analysis. All the compounds were screened for their antimicrobial activity by MIC method. Few of the molecules were found to be biologically potent. 2010 Elsevier Masson SAS. All rights reserved.Item Redetermination of methyl 3,4-O-isopropyl-idene-?-D-fucopyran-oside monohydrate(2009) Fun, H.-K.; Jebas, S.R.; Rai, S.; Shetty, P.; Isloor, A.M.In the title compound, C10H18O5 H2O, the fucopyran-oside ring adopts a chair conformation. The crystal packing is stabilized by inter-molecular O - H?O and C - H?O hydrogen bonds together with intra-molecular O?O [2.2936 (8) ] and inter-molecular O?O [2.7140 (8)-2.829 (3) ] short contacts. The mol-ecules are linked together to form an infinite chain along the a axis. This structure has been solved previously but with no R-values [Spiers (1931). Z. Kristallogr. Kristallgeom. Kristallphys. Kristallchem. 78, 101].Item N?-[(E)-(3-Phenyl-1H-pyrazol-4-yl)methylidene]naphtho-[2,1-b] furan-2-carbohydrazide monohydrate(2011) Fun, H.-K.; Loh, W.-S.; Malladi, S.; Ganesh, B.M.; Isloor, A.M.In the title hydrate, C23H16N4O 2 H2O, the pyrazole ring is approximately planar, with a maximum deviation of 0.023 (1) , and makes dihedral angles of 28.63 (6) and 46.44 (7) with the naphtho-[2,1-b]furan ring system and the benzene ring, respectively, In the crystal, O-H?N, O-H?O, N-H?O, N-H?N, C-H?O and C-H?N hydrogen bonds link the molecules, forming sheets lying parallel to the ab plane. The crystal structure also features C-H?? interactions involving the centroids of the pyrazole and benzene rings.Item Ethyl 1-cyclohexyl-5-(4-methoxyphenyl)-1H-pyrazole-4-carboxylate(2011) Fun, H.-K.; Quah, C.K.; Chandrakantha, B.; Isloor, A.M.; Shetty, P.In the title compound, C19H24N2O 3, the benzene ring forms a dihedral angle of 65.34 (7) with the pyrazole ring. The cyclo-hexane ring adopts a chair conformation. In the crystal, molecules are linked into a22(22) ring motifs.Item Ethyl 4-{[1-(2,4-dichlorobenzyl)-1 H- 1,2,3-triazol-4-yl]methoxy}-8- (trifluoro-methyl) quinoline-3-carboxylate(2012) Fun, H.-K.; Ooi, C.W.; Garudachari, B.; Isloor, A.M.; Rashid, S.A.In the title compound, C23H17Cl2F 3N4O3, the triazole ring makes dihedral angles of 50.27 (6) and 82.78 (7) with the quinoline ring system and the dichloro-substituted benzene ring. The dihedral angle between the quinoline and dichloro-substituted benzene rings is 38.17 (4) . In the crystal, molecules are linked via C - H N, C - H F and C - H O hydrogen bonds into a three-dimensional network. The crystal is further consolidated by C - H ? contacts to the triazole ring and inversion-related ?-? interactions between the benzene and pyridine rings of quinoline systems [centroid-centroid distance = 3.7037 (7) ].Item Ethyl 2-[(3-chloro-phen-yl)hydrazono]-3-oxobutanoate(2009) Fun, H.-K.; Padaki, M.; Sowmya; Isloor, A.M.; Chantrapromma, S.The mol-ecule of the title oxobutanoate derivative, C12H 13ClN2O3, adopts a keto-hydrazo tautomeric form and is roughly planar, the angle between the benzene ring and the mean plane through the hydrazone and aliphatic chain being 1.49 (6) . This planarity is further aided by the formation of an intra-molecular N - H?O hydrogen bond which generates an S(6) ring motif. The aromatic ring and aliphatic chain have a trans configuration with respect to the N - N bond. In the crystal packing, centrosymmetric R 2 2(16) dimers are formed through pairs of weak C - H?O(3-oxo) inter-actions. These dimers are linked together through weak C - H?O(carboxyl-ate C=O) inter-actions into ribbons along the b-axis direction. These ribbons are stacked along the a-axis direction. The crystal also exhibits Cl?Cl [3.4988 (6) ] and C?O [3.167 (2)-3.335 (2) ] short contacts.Item Ethyl 2-[(2,6-dimethylphenyl)-hydrazono]-3-oxobutanoate(2009) Fun, H.-K.; Jebas, S.R.; Padaki, M.; Hegde, C.; Isloor, A.M.The title compound, C14H18N2O3, crystallizes with two independent molecules in the asymmetric unit, having closely comparable geometries. Both molecules are essentially planar [maximum deviations from the mean plane of 0.069 (1) and 0.068 (1) for the two molecules] and contain an intramolecular N?H?O hydrogen bond which generates a ring with graph-set motif S(6). In the crystal, the molecules are linked into chains along the c axis by intermolecular C?H?O hydrogen bonds, and intermolecular C?H?? interactions are also present.Item Ethyl 2-[(4-chloro-phen-yl)hydrazono]-3-oxobutanoate(2009) Fun, H.-K.; Chantrapromma, S.; Padaki, M.; Radhika; Isloor, A.M.The mol-ecule of the title oxobutanoate derivative, C12H 13ClN2O3, is nearly planar; the inter-planar angle between the benzene ring and the mean plane through the hydrazono-3-oxobutanoate unit is 2.69 (3) . An intra-molecular N - H?O hydrogen bond generates an S(6) ring motif. In the crystal packing, C - H?O(3-oxo) inter-actions link mol-ecules into dimers. The dimers thus formed are linked through C - H?O(carboxyl-ate C=O) inter-actions, leading to the formation of ribbons along the [01 ] direction, which are stabilized via Cl?Cl [3.2916 (3) ] contacts. The ribbons are stacked via C?O contacts [3.2367 (12)-3.3948 (12) ].Item Diethyl 4-[5-(4-chlorophenyl)-1H-pyrazol-4-yl]-2,6-dimethyl-1,4-dihydro- pyridine-3,5-dicarboxylate(2012) Fun, H.-K.; Loh, W.-S.; Vijesh, A.M.; Isloor, A.M.; Malladi, S.In the title compound, C22H24ClN3O 4, intra-molecular C - H?O and C - H?N hydrogen bonds form S(9) and S(7) ring motifs, respectively. The 1,4-dihydro-pyridine ring adopts a flattened boat conformation. The benzene ring makes a dihedral angle of 33.36 (6) with the pyrazole ring. In the crystal, pairs of N - H?N hydrogen bonds link the molecules into inversion dimers. The dimers are stacked in column along the a axis through N - H?O and C - H?N hydrogen bonds. The crystal packing also features C - H?? inter-actions involving the pyrazole ring. Fun et al. 2012.