The first successful synthesis and isolation of a boronic acid was reported in 1860 by Frankland in the pursuit of novel organometallic compounds. For more than a century, further studies of boronic acids were sparsely published. Suzuki and Miyaura jumpstarted the field in 1979 with an innovative carbon-carbon bond forming reaction employing an organoboronic acid and a carbon halide under palladium catalysis. Indeed, the Nobel Prize in Chemistry was awarded to Professor Akira Suzuki, along with Professors Richard Heck and Ei-ichi Negishi, in 2010 for their important contributions in palladium-catalyzed cross-coupling chemistry. Over the last 30 years, reports on organoboron compounds have increased exponentially. This dissertation describes the author's contributions to the development of preparative methods for organoboronic acid derivatives using transition metal-catalyzed reactions of diboron reagents. A unique "mixed" diboron reagent was developed (PDIPA diboron) that contains sp2- and sp3-hybridized boron atoms, unambiguously confirmed by X-ray crystallography. PDIPA diboron is sufficiently activated internally through a dative-bonding amine to selectively transfer the sp2-hybridized boron regioselectively, in the presence of copper, to electron deficient alkenes including α,β-unsaturated ketones, esters, amides, aldehydes, and nitriles to provide the corresponding boratohomoenolates. A unique β,β-diboration of an α,β-acetylenic ketone was also discovered. The scope of PDIPA diboron reactions was then expanded to a set of substrates with a more complex structural backbone. Allenoates are α,β,γ-unsaturated esters with orthogonal pi systems, which pose several possible difficulties with the regioselectivity of addition, not to mention known isomerizations catalyzed by copper. However, we successfully installed the boron moiety regioselectively on the β-carbon of a variety of allenoates, providing a vinyl boronic ester, and also observed exclusive formation of the (Z)-isomer from racemic starting materials. The resulting vinyl boronic ester was then shown to be an excellent Suzuki-Miyaura cross-coupling partner, affording a diastereopure, trisubstituted alkene in quantitative yield. Commercially available bis(pinacolato)diboron has shown remarkable stability towards hydrolysis and autoxidation. Using this reagent, we developed a copper- and amine-catalyzed boration protocol performed entirely in water and open to air. Using only 1 mol% copper, extraordinary activity was observed. UV-Vis, 11B NMR, and solvent kinetic isotope experiments were employed to gain insight into the mechanism, which showed the possibility of autocatalysis. Attempts to control stereoselectivity were not successful, although these results were rationalized by a dynamic catalyst structure. / Ph. D.

Les cyclopropanes sont des motifs structuraux importants en chimie médicinale. Parmi les synthèses existantes du fragment aminocyclopropane, les réactions dérivées de la réaction de Kulinkovich, appliquées aux amides et aux nitriles, sont des méthodes simples d'accès. Cependant, il n'existe pas de version asymétrique efficace. Dans une première partie, l'étude de l'utilisation de complexes de titane optiquement actifs pour la préparation de spirolactames chiraux à partir de cyanoesters a été réalisée. Ce travail a permis de mettre au point une méthode d'évaluation rapide de ligands chiraux dont leur criblage a montré que les composés de la famille du Taddol fournissent les meilleurs excès énantiomériques. L'énantiosélectivité demeure cependant actuellement trop faible pour présenter un intérêt en synthèse. Dans une seconde partie, la synthèses de carbinamines tertiaires, un autre motif important, a été étudié à partir d'acylcyanhydrines et d'organométalliques. En particulier, la synthèse d'une bibliothèque d'acides aminés quaternaires a été entreprise à partir d'hydroxyamides. L'incorporation de deux organométalliques différents sur des acylcyanhydrines a été également effectuée conduisant à l'obtention d'hydroxyamides chiraux sous forme racémique. Enfin, l'emploi de réactifs organozinciques allyliques nous a permis d'accéder à de très bons rendements en produits de double addition. Ces hydroxyamides ont été ensuite valorisés comme précurseurs de plateformes multifonctionnelles pour la ligation chimique. / Cyclopropylamines are important scaffolds in medicinal chemistry. Among the syntheses of the aminocyclopropane moiety, the Kulinkovich-related reactions applied to amides and nitriles furnish straightforward access. However, no efficient asymmetric version has been published to date. In a first part, the study of optically active titanium complexes for the preparation of chiral spirolactams from cyanoesters has been undertaken. This work allowed us to setup a quick evaluation method for chiral ligands whose screening revealed that Taddol and its derivatives lead to the best enantiomeric excesses. However, the enantioselectivity remains too low for synthetic purposes. In a second part, the synthesis of tertiary carbinamines, another important scaffold, has been studied from acylcyanohydrins and organometallics. Notably, the synthesis of a quaternary aminoacids library was achieved. The incorporation of two different organometallics on acylcyanohydrins was also undertaken, leading to the preparation of chiral hydroxyamides in a racemic fashion. Lastly, very good yields in double addition products were obtained by using allylic organozinc reagents. The obtained hydroxyamides were used as precursors of polyfunctional linkers for the chemical ligation.

Sulfoxide-ligand exchange (SLE) and asymmetric halogen-metal exchange (AHME) processes were separately examined for the enantioselective synthesis of functionalized alpha-haloalkylmetal (carbenoid) reagents. Carbenoids derived from SLE were used to effect stereospecific reagent-controlled homologation (StReCH) of boronic esters and those generated via AHME were engaged in Darzens-type chemistry with aldehydes. Abstract for Part 1. Scalemic syn alpha-chloroalkylsulfoxides p-TolS(O)CHClR [R = allyl, (1,3-dioxolan-2-yl)methyl, proparygyl, and 2-(benzyloxy)ethyl] were prepared from the corresponding thioethers by Jackson-Ellman-Bolm catalytic enantioselective sulfoxidation [cat. VO(acac)₂, tert-leucinol derived chiral Schiff base ligand, aq. H₂O₂, CHCl₃; 76-80% yield, >98% ee] followed by non-racemizing chlorination mediated by N-chlorosuccinimide in the presence of potassium carbonate (84-86% yield, syn:anti ≥ 20:1). The corresponding anti diastereoisomers were accessed from their syn epimers by sodium hexamethyldisilazide mediated deprotonation (THF, –78 °C) followed by treatment with either CH₃OH or CD₃OD to yield alpha-[¹H] or alpha-[²H] isotopomers, respectively (88% yield, anti:syn ≥ 17:1). Allyl and (1,3- dioxan-2-yl)methyl substituted chlorosulfoxides reacted with R'Li (t-BuLi or PhLi, THF, –78 °C) to give the expected products of SLE [p-TolS(O)R' and LiCHClR or LiCDClR]; however, neither the benzylether nor propargyl substituted substrates gave wholly satisfactory results under the same reaction conditions. The functionalized carbenoid reagents so obtained, 1-chloro-3-butenyllithium and 1-chloro-2-(1,3- dioxolan-2-yl)ethyllithium, were applied to the StReCH of B-(2-chloropyrid-5-yl) pinacol boronate but only the latter gave acceptable yields of chain extended products. The anti alpha-[²H]-chlorosulfoxide dioxolanyl bearing carbenoid precursor gave superior results to the analogous syn or anti alpha-[¹H]-chlorosulfoxides for StReCH of the B-pyridyl boronate [79% conversion, ≥ 89% ee (99% stereofidelity), vs. ≤ 68% conversion for non-deuterated chlorosulfoxides]. The origin of this isotope effect was traced to a deleterious proton transfer pathway between the alpha- chloroalkyllithium reagent and its chlorosulfoxide precursor. Sequential double iterative StReCH of B-(2-chloropyrid-5-yl) pinacol boronate with two separate portions of (S)-1-[²H]-1-chloro-2-(1,3-dioxolan-2-yl)ethyllithium (generated via SLE with phenyllithium) followed by oxidative work-up (with KOOH) gave (1R,2R)-1,2- [²H]₂-2-(2-chloropyrid-5-yl)-1,2-bis[(1,3-dioxolan-2-yl)methyl]ethanol (40% yield, ≥ 98% ee, dr = 85:15). Substitution of the (R)-configured carbenoid for its antipode in the second StReCH stage above gave the unlike (1S,2R)-isomer of the same pyridylethanol derivative (49% yield, ≥ 98% ee, dr = 79:21). The unlike diastereoisomer was advanced to the trifluoroacetamide of (1R,2R)-1,2-[2H]2-1- amino-2-(2-chloropyrid-5-yl)cyclohex-4-ene (6 steps, 5% overall yield); the non- deuterated isotopomer of this compound was previously advanced to the analgesic alkaloid (–)-epibatidine by Corey and co-workers. Abstract for Part 2. Scalemic planar chiral N,N-dialkyl 2-iodoferrocene carboxamides envisioned as recyclable precursors to ferrocenyl metal reagents for AHME, were prepared from ferrocene carboxylic acid by a three step sequence of: acid chloride formation [(COCl)₂ and cat. DMF)], aminolysis (with R₂NH, R = Me, Et, i-Pr; 65- 80% yield over 2 steps), and sec-butyllithium/(–)-sparteine mediated enantioselective directed ortho-metallation (DoM) followed by iodinolysis (87% yield, ≥ 96% ee). Attempts to access more elaborate 5-substituted 2-iodoferrocene carboxamides via DoM/iodinolysis of ortho-substituted ferrocene carboxamides (Me, Ph, or SiMe₃ substituents) mostly failed; however, analogous trisubstituted ferrocene oxazolines could be synthesized. Treatment of N,N-diisopropyl 2-iodoferrocene carboxamide (298, ≥ 96% ee) with n-BuLi (THF, –78 °C) resulted in complete conversion to the corresponding lithioferrocene (327) via I/Li interchange; subsequent iodinolysis initiated reverse Li/I exchange and returned iodoferrocene 298 without diminished enantiomeric excess, establishing configurational stability for the lithiated ferrocene intermediate. Prochiral (RCHI₂) and racemic (RCHICl) geminal dihalide substrates for AHME studies were prepared by electrophilic quench of dihalomethylsodiums with either Ph(CH₂)₃I or Me₃SiCl (50-78% yield). Of the four dihalides so produced, only prochiral substrate Me₃SiCHI₂ engaged in I/Li exchange with scalemic lithioferrocene 327 resulting in regeneration of its precursor iodoferrocene 298 and the formation of a putative chiral carbenoid Me₃SiCHLiI. Trapping of the carbenoid with aldehydes RCHO (R = Ph, 4-MeOC₆H₄, Ph(CH₂)₂, c-C₆H₁₁) in the presence of Me₂AlCl gave the expected epoxysilane products (35-40% yield, cis:trans ≥ 2:1) but without discernable enantiomeric excess. Hypotheses to account for the apparent lack of stereoinduction in this AHME cycle are presented. Comparable experiments using analogous magnesiated ferrocenes failed to produce putative carbenoid species from the same set of geminal dihalide substrates. / Graduation date: 2012

© Springer Science+Business Media Dordrecht 2016 / Reducing AgNO3 by glucose at basic pH coated the surface of silica spheres with a high density of hemispherical silver nanoparticles (average diameter 3.2±1 nm). A much lower silver concentration than is standard favored heterogeneous nucleation of silver on the silica surface at the expense of homogeneous nucleation in solution. The slow growth rate of the nuclei promoted the formation of discrete silver particles rather than a continuous shell. Based on scanning electron microscopy and transmission electron microscopy, the surface coverage of silver seed particles was as high as 25% at 10 °C without prior functionalization of the silica. The particles were composed of metallic silver based on x-ray photoelectron spectroscopy. There was a sharp increase in the silver surface coverage and decrease in the particle size when the temperature was raised from 5 °C to 10 °C and the amount of silica was decreased from 0.2 to 0.025 V/V. The size was controlled by the diffusion barrier through the ion shell surrounding the silica spheres and by maintaining reaction conditions where the particles on the surface compete for silver.

Cancer testis antigens (CTA) represent attractive targets for targeted radiotherapy and imaging as their expression is restricted to cancer and germ cells. NY-ESO-1, a member of the CTA family, is highly immunogenic and expressed in multiple tumor types including carcinoma of bladder, liver lung. The aim of this study was to develop radioimmunoconjugates (RIC) to target NY-ESO-1 protein in cancer cells. Anti-NY-ESO-1 antibodies were modified by addition of DTPA for 111In-labelling or, in the presence of Iodogen, were 123I-labelled. Delivery of radiolabeled immunoconjugates across the cell membrane was achieved using a protein transfection (PT) reagent (SAINT-PhD) and by chemical linkage with the cell-penetrating and nuclear-localizing peptide, TAT (YGRKKRRQRRR). Cellular internalization, distribution and efflux of 111In-DTPA-anti-NY-ESO-1-TAT-PT and 123I-anti-NY-ESO-1-TAT-PT were investigated in cell fractionation and retention assays. It was shown that protein transfection reagent has promoted the cellular uptake of RICs into SK-MEL-37 and both of 111In-DTPA-anti-NY-ESO-1-TAT-PT and 123I-anti-NY-ESO-1-TAT-PT was retained longer in SK-MEL-37 cells in comparison to their isotope control RIC. In clonogenic assays, 111In-DTPA-anti-NY-ESO-1-TAT-PT significantly reduced surviving fraction of SK-MEL-37 cells. Cytotoxicity was inversely proportional to specific activity and the concentration of cells exposed to 111In-DTPA-anti-NY-ESO-1-TAT-PT. siRNA knock down of NY-ESO-1 resulted in partial reversal of 111In-DTPA-anti-NY-ESO-1-TAT-PT associated cytotoxicity. These promising results obtained from the in vitro study has brought the probe further into in vivo study. In preliminary biodistribution studies in SK-MEL-37 xenograft-bearing mice, tumour:muscle ratio for 111In-DTPA-anti-NY-ESO-1-TAT-PT was statistically significant compared to the control RIC 48 h post injection. This clearly indicated that the probe can be delivered into tumour in in vivo model and the successful uptake of radioactivity increased the chance of causing cytotoxicity to tumour cells through DNA damage. All of these findings have suggested that intracellular cancer associated antigen NY-ESO-1 can be reached by protein transfection reagent and cell penetrating peptide and initiates DNA damage through radio-isotope mediated cytotoxicity. Therefore, it represents a novel approach to the treatment of CTA-expressing cancers.

A disposição ambientalmente adequada dos resíduos sólidos em aterros sanitários requer atenção ao tratamento do lixiviado gerado, que atualmente representa um desafio aos engenheiros, técnicos e pesquisadores da área. Esse trabalho avalia a tratabilidade do lixiviado pelo processo oxidativo avançado Reagente de Fenton, seguido por tratamento consorciado com esgoto sanitário em biofiltro aerado submerso. Os ensaios com Reagente de Fenton foram realizados em escala de bancada, com tempo de duração de 70 min por batelada; constatou-se que a razão mássica mais eficiente em termos de remoção de DQO do lixiviado bruto foi de 2:1 (H2O2:Fe II). Os resultados mostraram que esse tratamento reduziu, em média, 62% da DQO do lixiviado bruto. Entretanto, houve acréscimo do teor de sólidos no efluente e formação de lodo. Quanto ao tratamento consorciado com esgoto sanitário, foram utilizados dois biofiltros aerados submersos - reator controle (R1) e reator R2, que recebia 2% de lixiviado tratado por reagente de Fenton - com vazões de 330 mL/h e 450 mL/h, respectivamente, ambos com tempo de detenção hidráulica de 12 h. No período monitorado e considerando as eficiências médias de remoção de DQO de 75% e 70% e de DBO de 95% e 88% nos reatores R1 e R2, respectivamente, não foi possível concluir se houve tratamento do lixiviado ou apenas diluição. Entretanto, foi observado que a adição de lixiviado comprometeu a eficiência de remoção de matéria orgânica na forma de COD, no biofiltro R2. / The environmentally sound disposal of solid waste in landfills requires attention to the treatment of the leachate generated, which currently represents a challenge to the engineers, technicians and researchers. This research assesses the treatability of leachate by advanced oxidation process Fenton\'s reagent, followed by combined treatment with sewage submerged aerated biofilters. Assays with Fenton\'s reagent were performed in a bench scale, with a duration of 70 min per batch, it was found that the most efficient weight ratio in terms of COD removal of crude leachate was 2:1 (H2O2:Fe II). Results shows that treatment decreased on average 62% of the COD of the crude leachate. However, there was an increase of solids in the effluent and sludge formation. As for combination with sewage treatment, two submerged aerated biofilters were used - control reactor (R1) and R2 reactor, which received 2% of treated leachate by Fenton\'s reagent - with flows of 330 mL/h and 450 mL/h, respectively, both with a hydraulic retention time of 12 h. In the monitored period and considering the average COD removal efficiencies of 75% and 70% of BOD and 95% and 88% in the reactors R1 and R2, respectively, it was not possible to conclude whether there was treatment of leachate or just dilution. However, it was observed that the addition of leachate compromised the efficiency of removal of organic material in the form of COD in the biofilter R2.

Devido à alta toxicidade, a produção e comercialização dos PCBs (Polychlorinated Biphenyls - Bifenilas Policloradas) estão proibidas no mundo todo. Esses compostos foram utilizados principalmente como base de misturas comerciais em óleos dielétricos para transformadores e capacitores. Hoje existem diversas áreas contaminadas com essas substâncias que são de difícil degradação ocasionada pela sua elevada estabilidade térmica e química. Há diversos estudos sobre diferentes técnicas de tratamento de áreas contaminadas por PCBs. A técnica proposta nesse trabalho foi a de oxidação química através do reagente de Fenton. Para isso, foi simulado em laboratório experimentos de tratamento de solo contaminados artificialmente por ascarel (mistura comercial de PCBs). A oxidação foi realizada segundo a técnica do planejamento experimental fatorial de dois níveis e duas variáveis. Manteve-se constante a concentração do contaminante - em torno de 6000 mg de PCB/ kg de solo - e variou-se a concentração de Fe2+ (0,04 a 0,1 mol/L) e H2O2 (2,07 a 4,15 mol/L). Os ensaios foram realizados ainda nos seguintes tempos de reação: 0, 5, 24 e 48 horas. A análise dos dados foi realizada através de cromatografia gasosa acoplada a um espectrômetro de massa - GC/MS. Dos resultados, concluiu-se que o experimento cuja concentração do reagente de Fenton era 4,15 mol/L de H2O2 e 0,04 mol/L de Fe2+, apresentou melhor percentual de remoção, em torno de 76% para o pentaclorobifenila, 67% para o hexaclorobifenila e 72% para o heptaclorobifenila. Além disso, observou-se que, dentro da região experimental estudada, o efeito da concentração de íons ferrosos foi mais significativo do que o causado pela concentração de peróxido de hidrogênio e que o mesmo tem um efeito negativo pois aumentando a concentração dos íons ferrosos diminui-se a remoção dos contaminantes. / Production and trading of polychlorinated biphenyls (PCBs) are prohibited at whole world due to their high toxicity. They were used mainly as dielectric oils for transformers and capacitors. Recently there are many contaminated areas with these compounds. The high thermic and chemistry stability of PCBs are responsible for their hard degradation. Many studies have been conducted about several techniques of soil remediation. The main purpose of this research is to study chemical oxidation using Fenton\'s reagent to soils treatment. It was simulated in laboratory experiments of soil treatment which was artificially contaminated with Ascarel (PCBs commercial mixture). Process oxidation was made according to factorial experimental planning technique of two levels and two variables (22). The contaminant concentration was constant - 6000 mg PCB/ kg soil - and it was varied the Fe2+ concentration (0,04 mol/L to 0,10 mol/L) and H2O2 concentration (2,07 mol/L to 4,15 mol/L). The times reaction of experiments were: 0, 5, 24 and 48 hours. It was used gas chromatography coupled with mass spectrometer - GC/MS. The better result shown removal rate of 76% to pentachlorobiphenyl, 67% to hexachlorobiphenyl and 72% to heptachlorobiphenyl, experimental conditions were Fe2+ concentration of 0,04 mol/L and H2O2 concentration of 4,15 mol/L. Besides it was observed that studied region the concentration effect of ferrous ions was more significant than concentration effect of hydrogen peroxide. The concentration effect of ferrous ions was negative on system because removal rate of contaminants decreases when [Fe2+] increases.

A disposição ambientalmente adequada dos resíduos sólidos em aterros sanitários requer atenção ao tratamento do lixiviado gerado, que atualmente representa um desafio aos engenheiros, técnicos e pesquisadores da área. Esse trabalho avalia a tratabilidade do lixiviado pelo processo oxidativo avançado Reagente de Fenton, seguido por tratamento consorciado com esgoto sanitário em biofiltro aerado submerso. Os ensaios com Reagente de Fenton foram realizados em escala de bancada, com tempo de duração de 70 min por batelada; constatou-se que a razão mássica mais eficiente em termos de remoção de DQO do lixiviado bruto foi de 2:1 (H2O2:Fe II). Os resultados mostraram que esse tratamento reduziu, em média, 62% da DQO do lixiviado bruto. Entretanto, houve acréscimo do teor de sólidos no efluente e formação de lodo. Quanto ao tratamento consorciado com esgoto sanitário, foram utilizados dois biofiltros aerados submersos - reator controle (R1) e reator R2, que recebia 2% de lixiviado tratado por reagente de Fenton - com vazões de 330 mL/h e 450 mL/h, respectivamente, ambos com tempo de detenção hidráulica de 12 h. No período monitorado e considerando as eficiências médias de remoção de DQO de 75% e 70% e de DBO de 95% e 88% nos reatores R1 e R2, respectivamente, não foi possível concluir se houve tratamento do lixiviado ou apenas diluição. Entretanto, foi observado que a adição de lixiviado comprometeu a eficiência de remoção de matéria orgânica na forma de COD, no biofiltro R2. / The environmentally sound disposal of solid waste in landfills requires attention to the treatment of the leachate generated, which currently represents a challenge to the engineers, technicians and researchers. This research assesses the treatability of leachate by advanced oxidation process Fenton\'s reagent, followed by combined treatment with sewage submerged aerated biofilters. Assays with Fenton\'s reagent were performed in a bench scale, with a duration of 70 min per batch, it was found that the most efficient weight ratio in terms of COD removal of crude leachate was 2:1 (H2O2:Fe II). Results shows that treatment decreased on average 62% of the COD of the crude leachate. However, there was an increase of solids in the effluent and sludge formation. As for combination with sewage treatment, two submerged aerated biofilters were used - control reactor (R1) and R2 reactor, which received 2% of treated leachate by Fenton\'s reagent - with flows of 330 mL/h and 450 mL/h, respectively, both with a hydraulic retention time of 12 h. In the monitored period and considering the average COD removal efficiencies of 75% and 70% of BOD and 95% and 88% in the reactors R1 and R2, respectively, it was not possible to conclude whether there was treatment of leachate or just dilution. However, it was observed that the addition of leachate compromised the efficiency of removal of organic material in the form of COD in the biofilter R2.

Neste trabalho foram desenvolvidos alguns estudos que tiveram como objetivo principal a transformação de furanoeliangolidos contendo a unidade -metileno--butirolactona em eremantolidos, através da reação de adição 1,4 de hidreto seguida de ciclização, realizada pelo reagente de Stryker [(Ph3PCuH)6]. / In this work we describe our studies for the biomimetic transformation of furanoheliangolides into eremantholides using the Strykers reagent [(Ph3PCuH)6].

Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2016-04-27T14:30:56Z No. of bitstreams: 1 PDF - Aluízio Gonçalves da Silva.pdf: 2861910 bytes, checksum: fec467664bbab2d62bb600299f8e0d10 (MD5) / Made available in DSpace on 2016-04-27T14:30:56Z (GMT). No. of bitstreams: 1 PDF - Aluízio Gonçalves da Silva.pdf: 2861910 bytes, checksum: fec467664bbab2d62bb600299f8e0d10 (MD5) Previous issue date: 2015-11-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Algal blooms and toxic cyanobacteria in fountains intended for human supply has been reported in many countries in recent decades due to impacts and human actions in the most diverse ecosystems on the planet. The presence of lineages of cyanobacteria producing cyanotoxins has negative effects on water bodies in particular in the intendend to the public supply due to the harmful effect of these substances on human health and animals. In general, cyanotoxins are not removed by conventional purifying water technologies. This study aimed to evaluate the efficiency of advanced oxidation process with the Fenton reagent in the oxidation of microcystin-LR water for public supply using conventional treatment steps coagulation, flocculation and sedimentation. The study water was prepared by adding the lysed cell cultivation Microcystis aeruginosa dechlorinated with potable water. Oxidation steps were performed, coagulation, flocculation and sedimentation JarTest programmed with rapid mixing -1 time of 10 s, rapid mixing gradient of 1000 s , flocculation time 20 min, flocculation gradient -1 -1 30 s and sedimentation velocity 1,4 cm.min . Different pH ranges were tested (2,0, 4,5 and + 7,0) and different concentrations of the Fenton reagent in the proportion of 1/3 H2O/Fe . The obtained results showed the oxidation of microcystin-LR in the treatments with pH 2,0; 4,5; and 7,0. By scanning the ions in the mass spectrometer it was possible to identify the peaks of mass/charge (m/z) fragments of enabling confirmation of oxidation by the presence of oxidation by products. Furthermore, after sedimentation the Fenton reagent enables significant removal being treatment T2 in time of 15 minutes the best for include percentage removal of turbidity 0,07 uT, true color 2,61 uH, COD 7,7 mg.L and MC-LR 0,07 μg.L. / Florações de algas e cianobactérias tóxicas em mananciais destinados ao abastecimento humano tem sido relatado em vários países nas últimas décadas devido aos impactos e ações do homem nos mais diversos ecossistemas do planeta. A presença de linhagens de cianobactérias produtoras de cianotoxinas tem efeitos negativo nos corpos hídricos em particular nos destinados ao abastecimento público devido ao efeito nocivo dessas substâncias à saúde humana e de animais. Em geral as cianotoxinas não são removidas pelas tecnologias convencionais de potabilização de água. O presente trabalho buscou avaliar a eficiência do processo de oxidação avançada com o reagente Fenton na oxidação da microcistina-LR de água destinada ao abastecimento público utilizando as etapas de tratamento convencional de coagulação, floculação e sedimentação. A água de estudo foi preparada com adição de cultivo de células lisadas de Microcystis aeruginosa com água potável desclorada. Foram realizadas as etapas de oxidação, coagulação, floculação e sedimentação em JarTest programado com tempo de -1 mistura rápida de 10 s, gradiente de mistura rápida 1000 s , tempo de floculação 20 min, -1 -1 gradiente de floculação 30 s e velocidade de sedimentação de 1,4 cm.min . Foram testados diferentes faixas de pH (2,0, 4,5, e 7,0) e diferentes concentrações do reagente Fenton na 2+ proporção de 1/3 de H2O/Fe . Os resultados obtidos mostraram a oxidação da microcistina-LR nos tratamentos com pH 2,0; 4,5; e 7,0. Através da varredura dos íons no espetrômetro de massas foi possível identificar os picos de massa/carga (m/z) dos fragmentos possibilitando a confirmação da oxidação através da presença dos subprodutos da oxidação. Além disso, após a sedimentação o reagente Fenton possibilitou a remoção significativa sendo tratamento T2 no tempo de 15 minutos o melhor por abrangir percentuais de remoção de turbidez 0,07 uT, cor verdadeira 2,61 uH, COD 7,7 mg.L e MC-LR 0,07 µg.L.