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Item Spectrophotometric determination of palladium(II) using piperonal thiosemicarbazone(2003) Shetty, P.; Nityananda, Shetty, A.; Gadag, R.V.A simple, rapid, selective and sensitive spectrophotometric method for the determination of palladium is proposed using piperonal thiosemicarbazone (PATS) as a reagent. The reagent forms a 1:2 complex (Pd:Reagent) with palladium. The yellow complex is soluble in 32-40% ethanol and has an absorption maximum at 363 nm. Beer's law is obeyed upto 3.85 ppm of palladium and the optimum concentration range is 0.5-2.45 ppm of Pd. The molar absorptivity and Sandell's sensitivity are 3. 80 x 104 dm3 mol-1 cm -1 and 2.8 x 10-3 ?g cm-2, respectively. The experimental conditions for complete colour development and the interference from various ions are investigated. The method is used for the determination of palladium in its complexes and synthetic mixtures.Item Thioacetamide as a releasing agent for the complexometric determination of thallium(iii) in its synthetic alloys and complexes(2007) Karthikeyan, J.; Parameshwara, P.; Nityananda, Shetty, A.; Shetty, P.A simple and selective complexometric method for the determination of thallium is proposed, based on the masking ability of thioacetamide towards thallium(III). Thallium present in a given sample solution is first complexed with a known excess of EDTA and the surplus EDTA is titrated with standard zinc sulphate solution at pH 5-6 (hexamine buffer) using xylenol orange as the indicator. A 0.8% aqueous solution of thioacetamide is then added to displace EDTA from the TI(III)-EDTA complex. The released EDTA is titrated with standard zinc sulphate solution as before. Reproducible and accurate results are obtained for 0.018 - 0.371 mol L-1(3.79mg - 75.91mg) of Tl(III) with relative error less than 0.43% and coefficient of variation not more than 0.26%. The interference of various ions was studied and the method was used for the analysis of thallium in its synthetic alloy mixtures and also in complexes.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 The inhibition action of N-furfuryl-N?-phenyl thiourea on the corrosion of mild steel in acid media(2006) Shetty, S.D.; Shetty, P.; Nayak, H.V.S.The inhibiting effect of N-furfuryl-N?-phenyl thiourea (FPTU) on the corrosion of mild steel in aqueous solutions of 0.05 and 0.1MHCl, as well as 0.025 and 0.05 M H2SO4 has been demonstrated using the potentiodynamic polarization technique. The polarization data showed that FPTU acts as an efficient anodic inhibitor for mild steel in both acid solutions. Avery high inhibition efficiency was evidenced in both acid solutions and it was found to vary with the concentration of the inhibitor and temperature. The obtained kinetic parameters of adsorption revealed spontaneous adsorption and a strong interaction of FPTU with the mild steel surface.Item T3P mediated synthesis of some new quinoline substituted pyrazole derivatives and its antibacterial studies(2012) Chandrakantha, B.; Isloor, A.M.; Peethambar, S.K.; Shetty, P.A series of new N-(substituted)-5-phenyl-1-(quinolin-2-yl)-1H-pyrazole-4-carboxamide derivatives (5a-h) have been synthesized by condensing ethyl-3-(dimethylamino)-2-[(phenyl)carbonyl]prop-2-enoate 2 with quinoline-2-yl-hydrazine. Compound 3 is hydrolyzed into 4 which is upon further coupled with different aromatic/aliphatic amines using 50% prpopyl phosphonic anhydride (T3P) in ethyl acetate as coupling reagent to afford different quinoline substituted pyrazole carboxamide derivatives. All the newly synthesized compounds were screened for their invitro antibacterial studies against Escherichia coli, Bacillus subtilis and Pseudomonas aeruginosa. The results revealed that compounds 5d, 5f, and 5h showed good antibacterial activity towards all bacterial strains. These newly synthesized compounds were characterized by NMR, mass spectral, IR spectral study and also by C, H, N analyses.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 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.