Notre équipe est l’un des partenaires du projet international PoMaRé (« Invertébrésbenthiques de Polynésie, Martinique et de la Réunion »). Nous travaillons encollaboration directe avec le Dr Cécile Debitus de l’IRD en Polynésie française, sonéquipe étant notamment en charge de collecter des échantillons d’éponges marinesdans différents atolls du Pacifique.Au laboratoire, nous nous sommes intéressés particulièrement à deux espècesabondantes en Polynésie : Dactylospongia metachromia et Dactylospongia elegans.Notre travail a consisté à isoler leurs métabolites spécialisés majoritaires : lesilimaquinones, puis à réaliser diverses études autour de ces deux sesquiterpènesquinoniques épimériques. Le travail s’est organisé de la façon suivante :- Extraction des ilimaquinones : les ilimaquinones ont été isolées de l’éponge Dactylospongia metachromia avec un rendement > 3 %. Une étude de la variation de leur pourcentage respectif par rapport à la géographie de collecte de l’éponge a été entreprise. Impliquant plus d’une centaine d’échantillons, c’est la première fois qu’une étude d’une telle ampleur est réalisée. L’éponge D. elegans a également été étudiée, nos études ont révélé la présence de l’ilimaquinone mais aussi d’une structure proche : l’isospongiaquinone.- Modifications structurales autour des ilimaquinones : Par voie chimique : des modifications ont été étudiées sur les ilimaquinones afin de cerner leur réactivité, divers analogues ont ainsi été obtenus. Entre autres, les substances naturelles isospongiaquinone, 5-epi-isospongiaquinone et néomamanuthaquinone ont pu être hémisynthétisées. Lors de ces études, une nouvelle réaction a été découverte modifiant la quinone de façon surprenante dans des conditions oxydantes. Par voie enzymatique : des micro-organismes ont été utilisés pour réaliser des biotransformations sur le squelette de l’ilimaquinone, trois composés ont été obtenus. Ces modifications ont touché à la fois la décaline et la quinone de notre substrat. Une réaction de fonctionnalisation originale a d’ailleurs pu être observée pour la première fois.- Modélisation moléculaire et électrochimie : une étude de modélisation moléculaire nous a permis de calculer l’énergie de formation des ilimaquinones en nous basant sur les hypothèses de biosynthèse que nous pouvons maintenant mieux appréhender. Finalement une étude d’électrochimie nous a permis d’évaluer les propriétés oxydo-réductrices de ces molécules naturelles à fortes potentialités en termes d’activités biologiques. / Our team is one of the partners of the international project PoMaRe ("Benthic Invertebrates of Polynesia, Martinique and Reunion"). We worked directly with Dr. Cécile Debitus from the IRD in French Polynesia, her team was in charge of collecting samples of marine sponges in different atolls of the Pacific.In the laboratory, we focused particularly on two abundant species in Polynesia: Dactylospongia metachromia and Dactylospongia elegans. Our job was to isolate their major metabolites: the ilimaquinones and perform various studies around these two epimeric sesquiterpene quinones.The work was organized as follows:- Extraction of ilimaquinones: ilimaquinones were isolated from the sponge Dactylospongia metachromia with a yield > 3%. A study of the variation of their respective percentage in relation with the geography of collection was undertaken, involving more than one hundred samples. This is the first study of this scale to be achieved. The sponge D. elegans was also studied, our results revealed the presence of ilimaquinone but also a nearby structure: isospongiaquinone.- Structural modifications of ilimaquinones:* Chemical modifications: structural changes were studied on ilimaquinones to delimit their reactivity: various analogues have been obtained. Among others, natural substances isospongiaquinone, 5-epi-isospongiaquinone and neomamanuthaquinone have been obtained. In these studies, a new reaction was discovered modifying the quinone surprisingly under oxidizing conditions.* Enzymatic modifications: micro-organisms were used to carry out biotransformations on the skeleton of ilimaquinone, three compounds were obtained. These changes have affected both the decalin and the quinone of our substrate. An original reaction has also been observed for the first time.- Molecular modeling and electrochemistry: a molecular modeling study has allowed us to calculate the energy of formation of ilimaquinones based on biosynthesis assumptions that we can now better understand. Finally an electrochemistry study evaluated the redox properties of these natural molecules with high potential in terms of biological activity.

L’aromaticité et l’antiaromaticité demeurent un sujet d’actualité au niveau fondamental puisque ces concepts permettent d’expliquer la réactivité de diverses classes de molécules. Certains composés polycycliques ayant une conjugaison π étendue, comme par exemple les tétraoxa[8]circulènes, ont des cycles aromatiques et antiaromatiques qui affectent leurs propriétés physicochimiques. Les oxacirculènes sont formés d’un anneau de quatre furanes et de quatre benzènes positionnés en alternance et créant un cœur formellement antiaromatique de cyclooctatétraène (COT). Malgré cela, ces composés démontrent une grande stabilité et peuvent servir en tant que composantes de dispositifs optoélectroniques comme des diodes électroluminescentes. Les propriétés optoélectroniques de ces composés et leur organisation moléculaire à l’état solide sont à l’origine d’un comportement unique. Le présent mémoire décrit la synthèse de tétraoxa[8]circulènes par une réaction très spéciale de cyclocondensation de 1,4-quinones catalysée par des acides, permettant d’accéder à des grandes molécules conjuguées en une étape. Les composés synthétisés ont une géométrie qui empêche leur empilement efficace et crée des vides dans la structure cristalline pouvant servir à l’inclusion de molécules invitées. En particulier, l’inclusion de C60 effectuée par cocristallisation cause l’uniformisation des longueurs des liens du cœur COT des oxacirculènes, suggérant des interactions de transfert de charge. Enfin, les propriétés optiques étudiées par spectroscopie UV-vis et par fluorescence indiquent que les oxacirculènes sont sensibles à leur environnement moléculaire et pourraient donc être utilisés comme des senseurs chimiques. / Aromaticity and antiaromaticity remain important topics of chemical research because these concepts explain the reactivity of various classes of molecules. For instance, certain polycyclic compounds with π-extended conjugation, such as tetraoxa[8]circulenes, contain both aromatic and antiaromatic rings, which affect their physicochemical properties. Oxacirculenes consist of a circular arrangement of four furan and four benzene rings positioned in an alternating fashion, thus creating a formally antiaromatic cyclooctatetraene (COT) core. Despite this, oxacirculenes exhibit great stability. They can serve as components in optoelectronic devices such as electroluminescent diodes, and their molecular organisation in the solid state can be controlled in ways that influence their properties. The present memoir describes the synthesis of tetraoxa[8]circulenes by a very special acid-catalysed cyclocondensation reaction starting from suitable 1,4-quinones, thereby allowing the preparation of large conjugated molecules in a single step. The compounds prepared have an awkward molecular structure that inhibits efficient packing and creates voids in the crystal structure, allowing the inclusion of guests. In particular, the inclusion of C60, achieved by cocrystallization, appears to create charge-transfer interactions as indicated by uniformization of bond lengths in the COT core. Optical properties studied by UV-vis spectroscopy and fluorescence show that oxacirculenes are sensitive to their local chemical environment, suggesting that they can be used as chemical sensors for the rapid detection of guests.

Neste trabalho são apresentados os resultados das determinações cristalinas, estruturais e supramoleculares, por difração de raio X, bem como os estudos de \"docking\" , de oito compostos derivados da 1,4-quinona. As estruturas resolvidas e refinadas mostraram a existência de ligações de hidrogênio, não convencionais intra e intermoleculares. Estas últimas permitiram entender o empacotamento cristalino em cada composto. Os resultados cristalográficos foram comparados com aqueles encontrados na literatura. Mas as estruturas correspondentes aos compostos AC1 (6,7-bis-fenilsulfanil-1,4-dihidro-1,4-metano-naftaleno-5,8-diona) e AC6 (6,7-bis-metilsulfanil-1,4-dihidro-1,4-metano-naftaleno-5,8-diol) possuem esqueletos químicos ainda não descritos na cristalografia. Os estudos de \"docking\" foram realizados utilizando as conformações cristalográficas dos oito compostos e da estrutura cristalográfica da tripanotiona redutase, uma proteína, dimérica, envolvida no sistema anti-stress oxidativo no Tripanosoma cruzi, parasita responsável pela enfermidade de Chagas. Foram, então, gerados complexos proteína-ligante no sítio da interface entre monômeros. Os complexos resultantes foram agrupados de acordo com orientações preferenciais e em cada grupo, a estrutura com menor energia total foi selecionada como representante do conjunto e analisado em tela gráfica. Para cada uma das moléculas foram realizados estudos detalhados das suas interações com todos os aminoácidos que as rodeavam. Finalmente, levando em conta as energias envolvidas e as interações foi possível escolher aquela que mostra o melhor encaixe. Dentre todas as moléculas, a AC8 [4a,8a-Dicloro-6-etilsulfanil-7-(metiletil-fenil-amino)-1,4,4a,8a-tetrahidro-1,4-metano-naftaleno-5,8,-diona] foi considerada como a mais promissora, a qual apresentou melhores resultados, um maior número de interações favoráveis com menor energia. / In this work the results of the crystal structure and supramolecular determination by X-ray diffraction together with docking studies, of eight compounds derived from 1,4-quinone, are presented. The solved and refined structures showed the existence of non-conventional hydrogen bonds, intra and inter-molecular. These last ones gave an insight about the crystal packing in each compound. The crystallographic results have been compared with those found in the literature. It should pointed out that structures of compounds AC1 (6,7-bis-phenylsulfanyl-1,4-dihydro-1,4-methano-naphthalene-5,8-dione) and AC6 (6,7-bis-methylsulfanyl-1,4-dihydro-1,4-methane-naphthalene-5,8-diol) have chemical skeletons which were not described before in crystallography. The docking studies have been carried out using the crystallographic conformations of the eight compounds and the crystallographic structure of trypanothione reductase, a dimmeric protein, involved in the anti-stress oxidative system of the Trypanosoma cruzi, the parasite responsible for the Chagas disease. The compounds were docked in the dimmer interface, which is the most likely binding site. The resulting complexes have been clustered together according with their orientation and of each group the one with the lowest total energy was chosen as representative of the cluster and analyzed in graphical screen. Thus, for that complex a detailed study of its interactions with all the neighbor amino acids was done. Finally, taking in account the energies and the interactions it was possible to choose the one that showed the best docking result. Amongst all molecules, the AC8 [4a,8a-dicloro-6-etilsulfanil-7-(metiletil-fenil-amino)-1,4,4a,8a-tetrahidro-1,4-methane-naftaleno-5,8,-diona] was considered as the most promising, which presented better results, a bigger number of favorable interactions with lesser energy.

Les dérivés réactifs de l'oxygène (ROS) sont considérés comme des messagers intracellulaires et sont produits principalement par les NADPH oxydases (Nox) dont Nox4 est l'un des représentants. Le dysfonctionnement de Nox4 est relié à de nombreuses pathologies (cancer, athérosclérose, hypertension pulmonaire ou arthrose). La régulation de l'activité NADPH oxydase de Nox4 est encore peu connue. L'objectif de ce travail est d'étudier l'activité NADPH oxydase et diaphorase (initiation du transfert d'électron) de Nox4.<br />Le clonage du gène de Nox4 a mis en évidence deux isoformes protéiques (Nox4A, forme entière et Nox4B, forme délétée d'un domaine de fixation du NADPH). La mise en place de deux modèles d'étude cellulaire (cellules HEK293E) et acellulaire (protéines recombinantes Nox4 tronquées) a permis d'obtenir les résultats suivants:<br />1) L'activité NADPH oxydase de Nox4A surexprimée dans les cellules HEK293E est constitutive et la partie C terminale cytosolique en milieu acellulaire possède une activité diaphorase. Par contre, Nox4B est inactive. <br />2) L'activité NADPH oxydase de Nox4 est inhibée par une série de composés quinones faiblement substitués (benzoquinone, hydroquinone, tMetBQ) et stimulée par d'autres quinones (tBuBQ, tBuBHQ, duroquinone, AA-861). L'implication du calcium et de la 5-lipoxygénase dans le mécanisme d'action des composés AA-861 et tBuBHQ a été écartée. Nos données convergent vers l'hypothèse d'une action directe des quinones sur la partie N terminale membranaire de Nox4.<br />Nous avons donc démontré que l'activité NADPH oxydase de Nox4 n'est pas seulement constitutive mais modulable par différentes quinones. Le mécanisme moléculaire précis reste à définir.

No description available.

Neste trabalho são apresentados os resultados das determinações cristalinas, estruturais e supramoleculares, por difração de raio X, bem como os estudos de \"docking\" , de oito compostos derivados da 1,4-quinona. As estruturas resolvidas e refinadas mostraram a existência de ligações de hidrogênio, não convencionais intra e intermoleculares. Estas últimas permitiram entender o empacotamento cristalino em cada composto. Os resultados cristalográficos foram comparados com aqueles encontrados na literatura. Mas as estruturas correspondentes aos compostos AC1 (6,7-bis-fenilsulfanil-1,4-dihidro-1,4-metano-naftaleno-5,8-diona) e AC6 (6,7-bis-metilsulfanil-1,4-dihidro-1,4-metano-naftaleno-5,8-diol) possuem esqueletos químicos ainda não descritos na cristalografia. Os estudos de \"docking\" foram realizados utilizando as conformações cristalográficas dos oito compostos e da estrutura cristalográfica da tripanotiona redutase, uma proteína, dimérica, envolvida no sistema anti-stress oxidativo no Tripanosoma cruzi, parasita responsável pela enfermidade de Chagas. Foram, então, gerados complexos proteína-ligante no sítio da interface entre monômeros. Os complexos resultantes foram agrupados de acordo com orientações preferenciais e em cada grupo, a estrutura com menor energia total foi selecionada como representante do conjunto e analisado em tela gráfica. Para cada uma das moléculas foram realizados estudos detalhados das suas interações com todos os aminoácidos que as rodeavam. Finalmente, levando em conta as energias envolvidas e as interações foi possível escolher aquela que mostra o melhor encaixe. Dentre todas as moléculas, a AC8 [4a,8a-Dicloro-6-etilsulfanil-7-(metiletil-fenil-amino)-1,4,4a,8a-tetrahidro-1,4-metano-naftaleno-5,8,-diona] foi considerada como a mais promissora, a qual apresentou melhores resultados, um maior número de interações favoráveis com menor energia. / In this work the results of the crystal structure and supramolecular determination by X-ray diffraction together with docking studies, of eight compounds derived from 1,4-quinone, are presented. The solved and refined structures showed the existence of non-conventional hydrogen bonds, intra and inter-molecular. These last ones gave an insight about the crystal packing in each compound. The crystallographic results have been compared with those found in the literature. It should pointed out that structures of compounds AC1 (6,7-bis-phenylsulfanyl-1,4-dihydro-1,4-methano-naphthalene-5,8-dione) and AC6 (6,7-bis-methylsulfanyl-1,4-dihydro-1,4-methane-naphthalene-5,8-diol) have chemical skeletons which were not described before in crystallography. The docking studies have been carried out using the crystallographic conformations of the eight compounds and the crystallographic structure of trypanothione reductase, a dimmeric protein, involved in the anti-stress oxidative system of the Trypanosoma cruzi, the parasite responsible for the Chagas disease. The compounds were docked in the dimmer interface, which is the most likely binding site. The resulting complexes have been clustered together according with their orientation and of each group the one with the lowest total energy was chosen as representative of the cluster and analyzed in graphical screen. Thus, for that complex a detailed study of its interactions with all the neighbor amino acids was done. Finally, taking in account the energies and the interactions it was possible to choose the one that showed the best docking result. Amongst all molecules, the AC8 [4a,8a-dicloro-6-etilsulfanil-7-(metiletil-fenil-amino)-1,4,4a,8a-tetrahidro-1,4-methane-naftaleno-5,8,-diona] was considered as the most promising, which presented better results, a bigger number of favorable interactions with lesser energy.

Molecular electrochemistry has proved to be very useful for characterizing redox reactions and deciphering chemical reaction mechanisms that are associated with electron transfer. It correlates strongly with redox-based medicine. In this study, we investigated the electrochemical behavior of pterocarpanquinones and selenoquinones, in protic and aprotic media, in the absence and presence of oxygen, in order to obtain data regarding their reduction mechanisms, reactivity with oxygen, the analysis of the stability of the electrogenerated intermediates and interactions with biological targets, like DNA. In typical measurements, CVs were recorded in aprotic medium (DMF + TBAPF6) to resemble the cell membrane environment. On the other hand, protic medium mimics the hydrophilic regions of the biological matrixes. This work shows cases of successful pharmacoelectrochemical investigations. In the first case, we investigate the electrochemical behavior of LQB-118, a pterocarpanquinone, which is anticancer and parasiticidal, with biological mechanisms of action related to the formation of ROS and interaction with DNA, among others. The cyclic voltammogram (VC) for LQB-118 in aprotic medium exhibits, at least, four waves. The first two are related to the usual reduction of quinones. The presence of additional waves suggests the clivage of the heterocyclic rings and the generation of additional reducible systems. A spectroelectrochemical investigation revealed the appearance of new absorption bands, which suggest the formation of the transient quinonamethide (QM). The QM was captured with thiophenol. In addition, electrochemical experiments were performed in the presence and absence of oxygen to verify the reactivity with oxygen, after the reduction of LQB-118 and its derivatives, with positive results. Studies with the ssDNA biosensor in solution showed positive interaction with LQB-118 and its electrogenerated products. The interaction of LQB-118 with CT-DNA was also evidenced by the fluorescence quenching technique. In the second case, CV was used to investigate the electrochemical behaviour of the antitumor selenoquinones. The obtained profiles confirmed the presence of two individual redox centres. All the compounds had shown electrochemical activity in the cathodic and anodic portions of the CVs. We also studied the behaviour of the compounds in protic medium. Electrochemical methods do well to predict the mechanism for adduct formation, structural rearrangement, generation of reactive oxigen species of pterocarpanquinones and appear well-adapted to explore redox pathways of all the compounds in vitro to be correlated to in vivo studies. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A eletroquímica molecular tem se mostrado muito útil para caracterizar reações redox e decifrar mecanismos reacionais associados à transferência de elétrons. Relaciona-se fortemente com a medicina redox. Neste estudo, investigou-se o comportamento eletroquímico de quinonas híbridas, tais como pterocarpanoquinonas e selenoquinonas, em meios prótico e aprótico, na ausência e presença de oxigênio, a fim de obter dados sobre seus mecanismos de redução e oxidação, reatividade com oxigênio, análise da estabilidade dos intermediários eletrogerados e interações com alvos biológicos importantes, como os tióis e o DNA. Em medidas típicas, os voltamogramas cíclicos (VCs) foram registrados em meio aprótico (DMF + TBABF6), para se assemelhar ao ambiente lipofílico, típico de membranas celulares. Por outro lado, o meio prótico mimetiza regiões hidrofílicas das matrizes biológicas. Este trabalho descreve dois casos de investigações farmacoeletroquímicas bem-sucedidas. No primeiro caso, investigou-se o comportamento eletroquímico da LQB-118, uma pterocarpanoquinona antitumoral e parasiticida, com mecanismos de ação relacionados à formação de espécies reativas de oxigênio (EROs) e interação com DNA, entre outros. Estudou-se também as pterocarpanoquinonas derivadas da LQB-118, mais precisamente seus derivados clorado, bromado e nitrado. O voltamograma cíclico (VC) para a LQB-118, em meio aprótico, exibe, pelo menos, quatro ondas catódicas. As duas primeiras são relacionadas com a redução habitual de quinonas. A presença de ondas adicionais sugere a quebra de anel heterocíclico e a geração de sistemas redutíveis adicionais. Investigação espectroeletroquímica revelou o surgimento de novas bandas de absorção, as quais sugerem a formação do quinonametídeo (QM) transiente. O QM foi capturado com tiofenol. Além disso, experimentos eletroquímicos foram realizados na presença e na ausência de oxigênio para verificar a reatividade com oxigênio, após a redução de LQB-118 e seus derivados, com resultados positivos. Estudos com o sensor de ssDNA, em solução, mostrou interação positiva com LQB-118 e seus produtos eletrogerados. A interação de LQB-118 com CT-DNA também foi evidenciada através da técnica de quenching de fluorescência. No segundo caso, a voltametria cíclica foi utilizada para investigar o comportamento eletroquímico de selenoquinonas antitumorais. Os perfis obtidos confirmam a presença de dois centros redox individuais. Todos os compostos mostraram atividade eletroquímica nas regiões anódica e catódica dos VCs. Estudou-se também o comportamento dos compostos em meio prótico e foi observada a formação de selenóxidos. Métodos eletroquímicos se mostraram adequados para prever rearranjos estruturais, formação de adutos, geração de espécies reativas de oxigênio, no caso de pterocarpanquinonas e para explorar caminhos redox in vitro das outras séries, correlacionando-se aos estudos in vivo.

Die Ziele dieser Arbeit waren die Darstellung der Naturstoffe Murrayachinon-B–E und Pyrayachinon-A–C, sowie die Synthese einiger nicht natürlicher, potentiell anti-Tuberkulose-aktiver Carbazole und Carbazolchinone. Für die Darstellung der aus der Pflanze Murraya euchrestifolia Hayata isolierten Naturstoffe wurden verschiedene synthetische Herangehensweisen untersucht: Die Transformation eines 7 Hydroxycarbazolchinons in die Zielverbindungen gelang nicht, ebenso wie die Syntheseroute über eine trioxygenierte Vorstufe. 7-Methoxy-3-methyl-1-tosyloxycarbazol (A) ließ sich jedoch in einer Ausbeute von 76 % über drei Stufen darstellen. Ausgehend von A konnten die Zielverbindungen regioselektiv in fünf bis sieben Stufen in Gesamtausbeuten von 10 % bis 46 % synthetisiert werden. Der Pyranring in Pyrayachinon-A wurde dabei über eine Sequenz aus Bromierung, Prenylierung, Cyclisierung und Oxidation aufgebaut. Die Anellierung der Pyranringe in Pyrayachinon-B und –C erfolgte, nach Methyletherspaltung an A in zwei Stufen. Die Einführung der Prenyl- und Geranylgruppen für die Synthese der Murrayachinone gelang durch reduktive Pyranringöffnung bzw. über eine Sequenz aus Methyletherspaltung, Propargylierung, partieller Hydrierung und Umlagerung. Außerdem wurde für Murrayafolin-B, Bismurrayafolin-B und -D über diese Syntheseroute ein Zugang geschaffen. Diese Verbindungen konnten, ausgehend von A, in sechs bzw. sieben Stufen in Gesamtausbeuten von 39 % bis 53 % dargestellt werden. Im Vergleich zu den bislang beschriebenen Synthesen dieser Verbindungen konnten alle Gesamtausbeuten signifikant gesteigert werden. Besonders hervorzuheben sind die Synthesen von Murrayafolin-B (bislang: 0.4 %, in dieser Arbeit: 40.0 %) und Pyrayachinon-A (bislang: 3.0 %, in dieser Arbeit: 22.1 %). Überdies wurde erstmalig die palladiumkatalysierte oxidative Cyclisierung eines O-tosylgeschützten Diarylamins zu einem Carbazol beschrieben. In Fortführung vorangegangener Arbeiten wurden zehn bislang nicht beschriebene Derivate des anti-Tuberkulose-aktiven 3-Methoxy-2-methylcarbazol-1,4-chinons dargestellt, darunter neun Carbazolchinone und ein Carbazol. Die Synthese der Carbazolchinone gelang palladiumkatalysiert in je vier bis sechs Stufen. Das Carbazol wurde eisenvermittelt über fünf Stufen dargestellt. Die Untersuchung der Aktivität gegenüber Mycobacterium tuberculosis steht noch aus.

Le XXIe siècle est une ère de progrès technologique sans précédent : jamais auparavant il ne nous n’a été possible de se déplacer et de communiquer aussi vite et loin. La démocratisation des transports et des appareils de communication modernes réduit cependant la disponibilité de ressources naturelles causant des problématiques socio-économiques et sanitaires globales comme la pollution ou des conflits politiques. Le contenu de cette thèse tente proposer des façons dont la conception rationnelle de matériaux organiques aux propriétés programmées pourrait améliorer la durabilité et les performances des cathodes de batteries Li-ion. Dans un premier temps, des stratégies permettant la construction contrôlée et ascendante d’assemblages cristallins organiques (essentiellement faits de carbone, hydrogène, oxygène et azote) seront présentées. Ensuite, différentes manières dont ces stratégies de constructions sont mises à contribution du développement de batteries Li-ion plus vertes seront exposées. Finalement, un projet de recherche reposant sur une expertise en chimie organique et en ingénierie cristalline pour la génération de matériaux aux propriétés pertinentes à de telles applications sera détaillé. / The 21st century marks an unprecedented era of technological advancement. Never before have we been able to travel and communicate as swiftly and extensively as we can now. While the accessibility of modern transportation and communication devices democratizes these capabilities, it also diminishes the availability of natural resources, giving rise to global socio-economic and health-related challenges such as pollution and political conflicts. The objective of this thesis is to propose methods by which the rational design of organic materials with programmed properties could improve both durability and sustainability of Li-ion batteries. Initially, the thesis outlines strategies for the controlled and bottom-up construction of organic crystalline assemblies primarily composed of carbon, hydrogen, oxygen, and nitrogen. Subsequently, various ways in which these construction strategies contribute to the development of more environmentally friendly Li-ion batteries are discussed. Finally, a research project is presented, centered around expertise in organic chemistry and crystal engineering for generating materials with properties relevant to such applications.

Os processos oxidativos avançados (POA) são uma alternativa para complementar os processos clássicos de tratamento de efluentes que podem não ser eficientes para remoção de alguns tipos de poluentes como, por exemplo, os poluentes emergentes. Os POA se baseiam na geração de espécies altamente reativas (radicais hidroxila), a partir de peróxido de hidrogênio (H2O2), que oxidam os poluentes. O H2O2 pode ser eletrogerado in situ pela reação de redução de oxigênio (RRO) no meio reacional. O uso de eletrodos de difusão gasosa (EDG) altamente porosos proporciona o suprimento de oxigênio na interface eletrodo/solução podendo aumentar a velocidade da RRO. O uso de modificadores como quinonas e azocompostos imobilizados à matriz de carbono dos EDG podem aumentar a geração de H2O2. Portanto, os modificadores orgânicos Sudan Red 7B (SR7B), metil-p-benzoquinona (MPB), ácido antraflávico (AA) e antraquinona-2-ácido carboxílico (A2CA) foram adicionados em diferentes teores ao carbono Printex L6 (CP) e microcamadas porosas destes materiais foram estudados por voltametria cíclica e de varredura linear em eletrodo de disco-anel rotatório (RRDE). Os materiais contendo 0,5% de SR7B e 5,0% de MPB levaram a aumento na eficiência de geração de H2O2 para 86,2 e 85,5%, respectivamente, em relação ao CP puro que levou a 82,8%. EDG de CP modificados com 0,5% de SR7B foram construídos com telas metálicas em sua faces externas e a aplicação de densidades de corrente de 75, 100 e 150 mA cm-2 levou a uma maior eletrogeração de H2O2. Em densidades de corrente de 75 mA cm-2, o EDG modificado gerou 1020,1 mg L-1 de H2O2 com consumo energético de 118,0 kWh kg-1 de H2O2, constante cinética aparente de 37,3 mg L-1 min-1 e eficiência de corrente de 17,9%, enquanto o EDG de CP puro gerou menor concentração de H2O2; 717, 3 mg L-1, com maior consumo energético; 168,5 kWh kg-1, menor constante cinética aparente; 21,4 mg L-1 min-1, e menor eficiência de corrente; 12,6%. Portanto, o EDG modificado poderia ser empregado em sistemas que precisem de altas gerações de H2O2. / The advanced oxidation processes (AOP) are an alternative to the classical processes of treatment of effluents that may not be effective for the removal of some types of pollutants such as emerging pollutants. The AOP are based on the highly reactive species (hydroxyl radicals) from hydrogen peroxide (H2O2), which oxidize pollutants. H2O2 can be electrogenerated in situ by the oxygen reduction reaction (ORR) in the reaction medium. The use of highly porous gas diffusion electrodes (GDE) provides the supply of oxygen at the electrode/solution interface, which can increase the RRO speed. The use of modifiers such as quinones and azocompounds immobilized on the carbon matrix of GDE may increase H2O2 generation. Therefore, the organic modifiers Sudan Red 7B (SR7B), methyl-p-benzoquinone (MPB), anthraflavic acid (AA) and anthraquinone-2-carboxylic acid (A2CA) were added in different contents to carbon Printex L6 (CP) and microporous layers of these materials were studied by cyclic voltammetry and linear sweep voltammetry on a rotating ring- disc electrode (RRDE). Materials with 0.5% of SR7B and 5.0% of MPB increased the current efficiency for electrogeneration of H2O2 to 86.2 and 85.5%, respectively, in relation to pure CP that leaded to 82.8%. GDE of CP modified with 0.5% of SR7B were constructed with metallic screens on their outer faces and an application of current densities of 75, 100 and 150 mA cm-2 led to a greater electrogeneration of H2O2. At current densities of 75 mA cm-2, the modified GDE generated 1020.1 mg L-1 of H2O2 with energy consumption of 118.0 kWh kg-1 of H2O2, apparent kinetic constant of 37.3 mg L-1 min-1 and current efficiency of 17.9%, while GDE of pure CP generated lower H2O2 concentration; 717, 3 mg L-1, with higher energy consumption; 168.5 kWh kg-1, lower apparent kinetic constant; 21.4 mg L-1 min-1, and lower current efficiency; 12.6%. Therefore, the modified GDE could be applied in systems that require high generations of H2O2.