1. Journal Articles
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Item The effect of glycine betaine additive on the PPSU/PSF ultrafiltration membrane performance(2016) Moideen, K, I.; Isloor, A.M.; Garudachari, B.; Ismail, A.F.A series of new ultrafiltration (UF) membranes were prepared by blending polyphenylsulfone and polysulfone with glycine betaine (GB) and polyethylene glycol-1000 (PEG-1000) as additive. GB of varying concentrations (0 2 wt.%) were dissolved in N-Methyl-2-pyrrolidone to prepare the membranes by phase inversion method. The membranes were characterized by Scanning Electron Microscope and dispersive X-ray analysis to study the asymmetric nature of membranes and the retention of GB in membranes, respectively. The stability tests were conducted to study the stability of additives in the membranes. The membrane hydrophilicity was determined by contact angle, porosity, water uptake, and permeability studies. The addition of GB additives enhanced the membrane performance like permeability, antifouling property, and heavy metal rejection. Also, the antifouling property improved with the addition of GB. The antifouling nature was calculated by flux recovery ratio, reversible and irreversible fouling. Polymer-enhanced UF of heavy metals like Pb2+ and Cd2+ was performed and rejection of 80.23 and 71.45%, respectively, was exhibited by the GB 1 membrane with agreeable permeability and antifouling property. 2016 Balaban Desalination Publications. All rights reserved.Item Synthesis, characterization, antioxidant, and anticancer studies of 6-[3-(4-chlorophenyl)-1H-pyrazol-4-yl]-3-[(2-naphthyloxy) methyl][1,2,4] triazolo[3,4-b][1,3,4]thiadiazole in HepG2 cell lines(2011) Sunil, D.; Isloor, A.M.; Shetty, P.; Satyamoorthy, K.; Prasad, A.S.B.Triazolo- thiadiazoles exhibit a variety of pharmacological properties, due to their cytotoxicity. In continuation of a previous study on triazolo-thiadiazoles, the authors have synthesized a new thiadiazole, 6-[3-(4-chlorophenyl)- 1-H-pyrazol-4-yl]-3-[(2-naphthyloxy)methyl] [1,2,4]triazolo[3,4-b][1,3,4]thiadiazole (CPNT), which was further characterized by advanced spectral techniques and elemental analysis. The compound exhibited a dose-dependent cytotoxic effect on hepatocellular carcinoma cell line, HepG2 with very low IC50 value of 0.8 ?g/ml in 24 h when compared with standard drug, doxorubicin. Incorporation of [3H] thymidine in conjunction with cell cycle analysis suggested that CPNT inhibited the growth of HepG2 cells. Flow cytometric studies revealed more percentage of cells in subG1 phase, indicating apoptosis, which was further confirmed through chromatin condensation studies by Hoechst staining. In vitro antioxidant activity of CPNT was determined by DPPH and ABTS free radical scavenging assays which revealed increasing scavenging activity with increasing concentration of the compound when compared with reference ascorbic acid. Springer Science+Business Media, LLC 2010.Item Synthesis, characterization, anticancer, and antioxidant activity of some new thiazolidin-4-ones in MCF-7 cells(2013) Isloor, A.M.; Sunil, D.; Shetty, P.; Malladi, S.; Pai, K.S.R.; Maliyakkl, N.There are limited studies centring on the potential of thiazolidin-4-ones as anticancer agents. In this study, a new series of 2-(3-substituted-1H- pyrazol-4-yl)-3-(3-substituted-5-sulfanyl-1,2,4-triazol-4-yl)-1, 3-thiazolidin-4-one (4a-o) have been synthesized by cyclo-condensation reaction of 5-substituted-4-[(3-substituted-1H-pyrazol-4-ylmethylidene)amino]-2H-1,2,4- triazole-3-thione (3a-o) and thioglycolic acid. The structures of all the synthesized compounds were confirmed by elemental analysis, spectral techniques like IR, 1H NMR, and mass spectroscopy. Few compounds exhibited dose-dependent cytotoxic effect in MTT assay in human breast cancer (MCF-7) cells. Apoptotic degradation of DNA due to action of potent thiazolidin-4-ones was analysed by agarose gel electrophoresis and visualized by ethidium bromide staining (comet assay). A concentration-dependent increase in tail length and olive tail moment was observed when treated with thiazolidin-4-ones. In vitro antioxidant studies like DPPH and ABTS-free radical scavenging assays-indicated moderate activity of thiazolidin-4-ones. 2012 Springer Science+Business Media, LLC.Item Synthesis, characterization and their anticonvulsant, anti-inflammatory studies of some novel chromeno oxadiazoles(2013) Ubaradka, S.R.; Isloor, A.M.; Shetty, P.; Shetty, P.; Isloor, N.A.In this study, a series of new 1,2,4-oxadiazole derivatives containing 3,4-dihydro-2H-chromen-2-amine moiety were synthesized by efficient microwave reaction of 2-amino-N?-hydroxychroman-3-carboxamidine and suitable aldehyde. Structures of all the synthesized compounds were confirmed by spectral studies and C, H, N analyses. Newly synthesized compounds were screened for their anticonvulsant and anti-inflammatory properties. Few of the compounds exhibited excellent anticonvulsant activity as compared to the standard drug Diazepam. Also compounds have exhibited moderate anti-inflammatory activity as compared to the standard drug Diclofenac sodium. 2012 Springer Science+Business Media, LLC.Item Synthesis, characterization and in vitro cytotoxic properties of some new Schiff and Mannich bases in Hep G2 cells(2011) Sunil, D.; Isloor, A.M.; Shetty, P.; Chandrakantha, B.; Satyamoorthy, K.A series of 5-substituted-4-amino-3-mercapto- 1,2,4-triazoles were synthesized and were treated with various 3-substituted pyrazole aldehydes to obtain a series of new Schiff bases (3a-l). Few of the selected Schiff bases were converted into Mannich bases by reaction with diphenylamine/morpholine in presence of formaldehyde in ethanol media (4a-e, 5a-e). These newly synthesized compounds were characterized by elemental analysis, IR, NMR and mass spectrometry studies. A comparative study on the cytotoxic activities of few selected Schiff and Mannich bases was done in HepG2 cells using MTT assay. Few of the screened Schiff bases, 3a, 3d, 3e, 3g and 3h showed dose dependent cytotoxic activity, 3a being the most potent with an IC50 value of 0.018 g/l comparable to the standard drug doxorubicin. Among the Mannich bases, 5b was the most active with an IC50 value of 0.034 g/l. The Schiff bases were found to be more active, when compared to Mannich bases derived from them. The morpholine derived Mannich bases were more potent than those obtained from diphenyl amine. Springer Science+Business Media, LLC 2010.Item Synthesis, characterization and desalination study of composite NF membranes of novel Poly[(4-aminophenyl)sulfonyl]butanediamide (PASB) and methyalated Poly[(4-aminophenyl)sulfonyl]butanediamide (mPASB) with Polysulfone (PSf)(2013) Padaki, M.; Isloor, A.M.; Kumar, R.; Fauzi, Ismail, A.; Matsuura, T.In the present investigation, Poly [(4-aminophenyl)sulfonyl]butanediamide (PASB) and methylated Poly[(4-aminophenyl)sulfonyl] butanediamide (mPASB) polymers were synthesized, using succinyl chloride and substituted 4-amino-1-benzenesulphonamide. Polysulfone composite membranes were prepared by blending these novel polymers by Diffusion Induced Phase Separation (DIPS) method. The performance of the membrane was studied in terms of salt rejection, water flux and molecular weight cutoff. The prepared membranes were hydrophilic in nature, which was confirmed by water uptake studies and contact angle measurement. All the membranes showed 1000. Da molecular weight cutoff. A maximum NaCl rejection of 52% was observed in some of the membranes. The effect of feed NaCl concentration on the NaCl rejection was also studied. The resistance of the membranes in a wide pH range was studied by water uptake measurement. Antifouling properties of the membranes were also performed using Bovine Serum Albumin (BSA) solution. 2012 Elsevier B.V.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, 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 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.