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Item The inhibition action of ethyl-2-phenyl hydrozono-3-oxobutyrate on the corrosion of 6061 Al alloy/SiCp composite in hydrochloric acid medium(2010) Kini, U.A.; Shetty, P.; Shetty, S.D.; Isloor, A.M.; Herle, R.The inhibition behavior of ethyl-2-phenyl hydrozono-3-oxobutyrate on the corrosion of 6061 Al alloy/SiCp composite in 0.1, 0.5 and 1 N hydrochloric acid solution at four different temperatures (30-60 C) has been investigated using potentiostatic polarization techniques and weight loss method. The results indicated that the corrosion inhibition efficiency and the extent of surface coverage were increased with the increase in inhibitor concentration up to a critical concentration. The adsorption of the inhibitor compound on the composite surface was found to obey Temkins' and Langmuir adsorption isotherms. The potentiostatic polarization results have revealed that oxobutyrate acts as an efficient cathodic inhibitor for the corrosion of 6061 Al alloy/SiCp composite in HCl medium. The thermodynamic parameters for the corrosion and adsorption processes were determined. 2010.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, characterization and biological activities of some new benzo[b]thiophene derivatives(2010) Isloor, A.M.; Kalluraya, B.; Sridhar, Pai, K.Benzo[b]thiophene molecules are found to be important tools in synthetic medicinal chemistry. They are of current interest due to their wide spectrum of pharmacological properties. In view of the biological activities of benzo[b]thiophene containing molecules, in this present research work, we propose the synthesis of some new benzo[b]thiophene derivatives such as thiadiazoles, oxadiazoles, pyrazolin & diaryl pyrazoles starting from 3-chlorobenzo[b]thiophene-2-carboxyl chloride. These newly synthesized compounds were characterized by elemental analyses, I.R, NMR and Mass spectral studies. Some of the selected compounds were screened for their antibacterial, antifungal and anti-inflammatory studies. Many of the molecules were found to be potent. 2009 Elsevier Masson SAS. All rights reserved.Item Synthesis, characterization and biological activity of some new 1,3,4-oxadiazole bearing 2-flouro-4-methoxy phenyl moiety(2010) Chandrakantha, B.; Shetty, P.; Nambiyar, V.; Isloor, N.; Isloor, A.M.In the present study a series of new 1,3,4-oxadiazole derivatives containing 2-fluoro-4-methoxy moiety were synthesized. These newly synthesized compounds were characterized by NMR, mass spectral, IR spectral study and also by C, H, N analyses. All the newly synthesized compounds were screened for their antibacterial and antifungal studies. Antimicrobial studies revealed that compounds 4a and 4b showed significant antibacterial activity against Escherichia coli and Pseudomonas aeruginosa Compound 4i showed significant antifungal activity against C. albicans. 2009 Elsevier Masson SAS. All rights reserved.Item Synthesis, characterization and anti-microbial studies of some novel 2,4-disubstituted thiazoles(2010) Vijesh, A.M.; Isloor, A.M.; Prabhu, V.; Ahmad, S.; Malladi, S.In the present study a series of novel 2,4-disubstituted thiazole derivatives containing substituted pyrazole moiety was synthesized by the reaction of 3-Aryl-1H-pyrazole-4-carbaldehyde thiosemicarbazone with 6-Bromo/H-3-(bromoacetyl)-2H-chromen-2-one/phenacyl chloride. Structures of newly synthesized compounds were characterized by spectral studies. New compounds were screened for their antibacterial studies against Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa. The results revealed that compounds 7c, 8e, and 8f having 2,5-dichlorothiophene substituent and 8c, 8d having 2,4-dichlorophenyl substituent showed significant antibacterial activity against all tested microorganisms. 2010 Elsevier Masson SAS. All rights reserved.Item Synthesis, characterization & impedance studies of some new nano filtration membranes(2010) Padaki, M.; Hegde, C.; Isloor, A.M.In the recent years membrane technology has gained significant attention from polymer chemists all around the world due to their attractive features such as efficiency, low costs, low energy costs and as effective solutions to longstanding problems in the chemical industries. Membrane technologies have been widely applied in the separation of liquids and even gases. Many separation problems can be solved economically by nanofiltration alone or in combination with other separation processes. This study aimed to synthesize polysulfone based nanofiltration membranes using DIPS (diffusion induced phase separation) technique. Newly synthesized polymer membranes were subjected to Infra red spectral and water uptake studies. Membranes were also characterized using electrochemical spectroscopy for their proton conducting property. Their surface morphology is visualized by SEM. (2010) Trans Tech Publications.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 Regioselective reaction: Synthesis, characterization and pharmacological studies of some new Mannich bases derived from 1,2,4-triazoles(2009) Isloor, A.M.; Kalluraya, B.; Shetty, P.In the present investigation, a series of new 4[(3-substituted-1H-pyrazol-4-yl)methyleneamino]-5-substituted-2-[(4-methylpiperzine-1-yl)methyl]-2H-1,2,4-triazole-3(4H)-thiones (4) were synthesized by the aminomethylation of 4-(3-substituted-1H-pyrazol-3-yl)methyleneamino-5-substituted-4H-1,2,4-triazole-3-thiols (3) with formaldehyde and N-methylpiperzine. These newly synthesized Schiff and Mannich bases were characterized by IR, 1H NMR, mass spectral data and elemental analyses. These compounds were screened for their antibacterial and antifungal activity. Some of the compounds were found to exhibit significant antimicrobial activity. 2009 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 Methyl 2,6-bis-[(5-bromo-4,6-dimethoxypyrimidin-2-yl)oxy]benzoate(2010) Fun, H.-K.; Goh, J.H.; Rai, S.; Isloor, A.M.; Shetty, P.In the title compound, C20H18Br2N 4O8, the inter-planar angle of the pyrimidine rings is 75.1 (2) . The central benzene ring is inclined at inter-planar angles of 66.5 (2) and 71.9 (2) with respect to the two pyrimidine rings. In the crystal structure, adjacent molecules are connected into two-molecule-thick arrays parallel to the bc plane via short Br?Br [3.5328 (12) ] and Br?O [3.206 (3) and 3.301 (4) ] inter-actions. A weak inter-molecular ?-? aromatic stacking inter-action [centroid-centroid distance = 3.526 (3) ] is also observed.