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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, characterization and antibacterial activity of some new pyrazole based Schiff bases(2013) Malladi, S.; Isloor, A.M.; Isloor, S.; Akhila, D.S.; Fun, H.-K.In the present study a series of new Schiff bases were synthesized. All the synthesized compounds were characterized by IR, 1H NMR, mass spectral and elemental analyses. Newly synthesized compounds were screened for their antibacterial (Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa) activity. The results revealed that, compounds 3f and 3c have exhibited significant biological activity against the tested microorganisms. 2011.Item Synthesis, characterization and antimicrobial studies of some new trifluoromethyl quinoline-3-carbohydrazide and 1,3,4-oxadiazoles(2014) Garudachari, B.; Isloor, A.M.; Satyanarayan, M.N.; Ananda, K.; Fun, H.-K.The present paper describes the synthesis of two new series of 7-(trifluoromethyl)-4-hydroxy substituted quinoline carbohydrazide derivatives (6a-e and 7a-g) and N-alkyl-3-(5-phenyl-1,3,4-oxadiazol-2-yl)-7- (trifluoromethyl) quinolin-4-amine derivatives (9a-f). Newly synthesized compounds were characterized by spectral studies. The structure of 9a was evidenced by X-ray crystallographic study. Synthesized compounds were screened for their antibacterial performance against Mycobacterium smegmatis and Pseudomonas aeruginosa. Antifungal activity was also carried out on the fungal stains Candida albicans and Penicillium chrysogenum. Compounds 7a and 9c showed significant antimicrobial activity against all the tested microorganisms. Among all the compounds, 6d and 6e showed the lowest MIC value of 6.25 ?g mL -1 against Mycobacterium smegmatis indicating these compounds can be possible future antituberculosis agents. 2014 the Partner Organisations.Item Synthesis, and antitubercular and antimicrobial activity of 1?-(4-chlorophenyl)pyrazole containing 3,5-disubstituted pyrazoline derivatives(2016) Harikrishna, N.; Isloor, A.M.; Ananda, K.; Obaid, A.; Fun, H.-K.A new series of 1?-(4-chlorophenyl)-5-(substituted aryl)-3?-(substituted aryl)-3,4-dihydro-2H,1?H-[3,4?]bipyrazolyl derivatives (6a-e, 8a-e, 10a-e) have been synthesized, characterized and screened for antimicrobial and antitubercular activity. Among the synthesized compounds, the minimum inhibition concentration of 10e was found to be as low as 1.56 ?g ml-1 and that of 10c was 6.25 ?g ml-1 as compared to the standard anti-tb drugs pyrazinamide and streptomycin. The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2016.Item Synthesis and performance characterization of PS-PPEES nanoporous membranes with nonwoven porous support(2013) Hegde, C.; Isloor, A.M.; Padaki, M.; Fun, H.-K.The present work describes about the synthesis and characterization of Polysulfone blend nanoporous membrane with nonwoven support. This Nonwoven support provides mechanical strength to membrane while filtration process and minimizes membrane fouling. Hence it helps in better membrane performance in terms of salt rejection, improved flux, thermal stability and fairly increases in proton conductivity. In this work we have used K.C.270 nonwoven material consisting of fine polyester fibers and has a thickness of below 110. ?m. 2011.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 Syntheses, crystal structures and antimicrobial studies of two new semicarbazone derivatives(2014) Chia, T.S.; Quah, C.K.; Ooi, C.W.; Garudachari, B.; Isloor, N.A.; Isloor, A.M.; Fun, H.-K.Two new derivatives of semicarbazone, (E)-2-(hexan-2-ylidene) hydrazinecarboxamide and (E)-2-(heptan-2-ylidene)hydrazinecarboxamide were synthesized and characterized by IR and 1H NMR. Their crystal structures were characterized by X-ray diffraction method. Compound (I) crystallizes in triclinic P 1 ?, a = 6.7679(7) , b = 7.1912(8) , c = 9.9969(11) , ? = 108.824(2), ? = 99.398(3), ? = 92.680(2), V = 451.75(8) 3, Z = 2, R 1 = 0.043 and wR 2 = 0.140. Compound (II) crystallizes in triclinic P 1 ?, a = 6.7192(6) , b = 7.2094(6) , c = 11.2842(11) , ? = 103.303(2), ? = 106.198(2), ? = 91.219(1), V = 508.70(8) 3, Z = 2, R 1 = 0.044 and wR 2 = 0.133. Their molecules adopt a L-shape conformation with C atom in C=N double bond acting as the junction point. The C=O double bond indicate the existence of semicarbazone group in keto-like form for both compounds in their solid state. In the crystal, the carbonyl O atom for both derivatives acts as a common acceptor in the intermolecular bifurcated N-H O hydrogen bonding which linked the molecules into one-dimensional supramolecular ribbons. Antimicrobial studies by serial dilution method showed both compounds exhibit antibacterial property. Graphical Abstract: Two new semicarbazone derivatives are characterized by IR, 1H NMR and single crystal X-ray diffraction methods and their antibacterial activity was further investigated by screening against four different bacterial strains.[Figure not available: see fulltext.] 2013 Springer Science+Business Media New York.Item Synthesis and antimicrobial activities of some novel 1,2,4-triazole derivatives(2013) Mange, Y.J.; Isloor, A.M.; Malladi, S.; Isloor, S.; Fun, H.-K.In the present investigation, a series of new Schiff bases 4a-f were synthesized by the condensation of N-[(4-amino-5-sulfanyl-4. H-1,2,4-triazol-3-yl)methyl]-4-substituted-benzamides 3a-b with various substituted aromatic aldehydes in ethanol-dioxane mixture using catalytic amount of sulfuric acid. The starting materials 3a-b were in turn synthesized by the fusion of benzoyl glycine/substituted benzoylglycine with thiocarbohydrazide. Newly synthesized compounds were characterized by IR, NMR, mass spectra and elemental analyses. All the compounds were evaluated for their antibacterial and antifungal activity using the Minimum Inhibition Concentration (MIC) method by serial dilution technique. Few of the compounds were found to be biologically active. 2011.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 Probing the morphology and anti-organic fouling behaviour of a polyetherimide membrane modified with hydrophilic organic acids as additives(2015) Hebbar, R.S.; Isloor, A.M.; Ismail, A.F.; Shilton, S.J.; Obaid, A.; Fun, H.-K.A facile approach for the preparation of an organic antifouling polymer membrane has been developed using low molecular weight organic acids as additives. The presence of these additives in the membrane was analysed by FTIR spectroscopy. The properties of the modified membranes were investigated in terms of contact angle, water uptake capacity, SEM and AFM analysis. These additives exerted a strong impact on the rheological properties of the casting solution, thereby altering the membrane morphology, surface roughness, water flux and the hydrophilicity of the membranes, as compared to those of the pristine polyetherimide (PEI) membrane. The organic antifouling properties of the modified membrane were analysed by filtering both bovine serum albumin (BSA) and humic acid solutions. The results showed that the additives exhibited a remarkable improvement in the antifouling properties (FRR of 72%) and a humic acid rejection of up to 86%. These outcomes offer new insights into the use of cheaper and readily available organic acids as additives, compared to the traditional, synthetic polymer materials as additives in membrane preparation. 2015 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.