No / Ethylmethanesulphonate (EMS), benzidine (BZD) and benzo[a]pyrene (B[a]P) were assayed for ability to induce mutation at the hprt locus of wild-type L5178Y mouse lymphoma cells. EMS was assayed in the absence of metabolic activation, B[a]P in the presence of metabolic activation (S-9 mix) and BZD both in the absence and presence of S-9. Treatment with EMS minus S-9 and B[a]P plus S-9, especially when the S-9 content of the incubation was 2% (v/v), produced strong dose-related increases in mutant frequency. BZD failed to induce mutation at the hprt locus, either in the absence or presence of S-9.

Neste trabalho demonstramos a preparação de fluorenos e benzo[b]fluorenos por uma nova rota sintética, baseada na reação de Diels-Alder de derivados benzo[5]radialênicos. Para a preparação destes últimos investigamos diversas estratégias, partindo de p-benzoquinona e três dienos: 1,1-dimetoxiciclopentadieno, 6,6-dimetilfulveno e 6-acetoxifulveno. A partir de cada fulveno obtivemos um benzo[5]radialeno diferente, sendo que o derivado dimetilado se mostrou inerte como dieno em cicloadições. O benzo[5]radialeno derivado do 6-acetoxifulveno, reagiu com diversos dienófilos tais como p-benzoquinona, 2,3-dicloro-p-benzoquinona, 1,4-naftoquinona, N-metilmaleimida, acetilenodicarboxilato de dimetila, acrilato de metila, etc. Notamos uma alta quimiosseletividade entre os sistemas diênicos, pois obtivemos apenas adutos trans. Com alguns dienófilos observamos a formação de compostos aromatizados (formados pela eliminação de ácido acético que, para os casos pertinentes, foi regiosseletiva). Com dienófilos como acrilato de metila ou sulfinil-naftoquinonas, alta regiosseletividade foi observada. Tentamos explorar tais seletividades para a preparação de análogos da eucapsitriona. Os adutos de Diels-Alder obtidos constituem exemplos de derivados fluorênicos e benzo[b]fluorênicos que, ultimamente, têm recebido grande atenção tanto por aspectos estruturais como por apresentarem propriedades biológicas importantes / In this work we demonstrated the preparation of fluorenes and benzo[b]fluorenes by a new synthetic route, based on the Diels-Alder reaction of benzo[5]radialenes derivatives. For the preparation of the last we investigated several strategies starting from p-benzoquinone and three dienes: 1,1-dimethoxycyclopentadiene, 6,6-dimethylfulvene and 6-acetoxyfulvene. From each fulvene we obtained a different benzo[5]radialene, but the dimethylated one showed no reactivity in cycloadditions. The benzo[5]radialene prepared from 6-acetoxyfulvene reacted with several dienophiles such as p-benzoquinone, 2,3-dichloro-p-benzoquinone, 1,4-naphtoquinone, N-methylmaleimide, dimethyl acetylenedicarboxylate, methyl acrylate, etc. We noted a high quimiosselectivity between the dienic sub units since only trans adducts were obtained. With some dienophiles we observed the formation of aromatized compounds (formed by acetic acid elimination which, for suitable cases, was regiosselective). With dienophiles such as methyl acrylate or sulfinyl-naphtoquinones high regiosselectivity was observed. We tried to explore such selectivities to prepare eucapsitrione analogues. These Diels-Alder adducts are examples of fluorenic and benzo[b]fluorenic derivatives, compounds that have gained considerable attention due to structural and biological aspects.

Neste trabalho demonstramos a preparação de fluorenos e benzo[b]fluorenos por uma nova rota sintética, baseada na reação de Diels-Alder de derivados benzo[5]radialênicos. Para a preparação destes últimos investigamos diversas estratégias, partindo de p-benzoquinona e três dienos: 1,1-dimetoxiciclopentadieno, 6,6-dimetilfulveno e 6-acetoxifulveno. A partir de cada fulveno obtivemos um benzo[5]radialeno diferente, sendo que o derivado dimetilado se mostrou inerte como dieno em cicloadições. O benzo[5]radialeno derivado do 6-acetoxifulveno, reagiu com diversos dienófilos tais como p-benzoquinona, 2,3-dicloro-p-benzoquinona, 1,4-naftoquinona, N-metilmaleimida, acetilenodicarboxilato de dimetila, acrilato de metila, etc. Notamos uma alta quimiosseletividade entre os sistemas diênicos, pois obtivemos apenas adutos trans. Com alguns dienófilos observamos a formação de compostos aromatizados (formados pela eliminação de ácido acético que, para os casos pertinentes, foi regiosseletiva). Com dienófilos como acrilato de metila ou sulfinil-naftoquinonas, alta regiosseletividade foi observada. Tentamos explorar tais seletividades para a preparação de análogos da eucapsitriona. Os adutos de Diels-Alder obtidos constituem exemplos de derivados fluorênicos e benzo[b]fluorênicos que, ultimamente, têm recebido grande atenção tanto por aspectos estruturais como por apresentarem propriedades biológicas importantes / In this work we demonstrated the preparation of fluorenes and benzo[b]fluorenes by a new synthetic route, based on the Diels-Alder reaction of benzo[5]radialenes derivatives. For the preparation of the last we investigated several strategies starting from p-benzoquinone and three dienes: 1,1-dimethoxycyclopentadiene, 6,6-dimethylfulvene and 6-acetoxyfulvene. From each fulvene we obtained a different benzo[5]radialene, but the dimethylated one showed no reactivity in cycloadditions. The benzo[5]radialene prepared from 6-acetoxyfulvene reacted with several dienophiles such as p-benzoquinone, 2,3-dichloro-p-benzoquinone, 1,4-naphtoquinone, N-methylmaleimide, dimethyl acetylenedicarboxylate, methyl acrylate, etc. We noted a high quimiosselectivity between the dienic sub units since only trans adducts were obtained. With some dienophiles we observed the formation of aromatized compounds (formed by acetic acid elimination which, for suitable cases, was regiosselective). With dienophiles such as methyl acrylate or sulfinyl-naphtoquinones high regiosselectivity was observed. We tried to explore such selectivities to prepare eucapsitrione analogues. These Diels-Alder adducts are examples of fluorenic and benzo[b]fluorenic derivatives, compounds that have gained considerable attention due to structural and biological aspects.

Parmi les agents antitumoraux exprimant une activité sur les topoisomérases, les alcaloïdes de la famille des benzo[c]phénanthridines (BZP) sont bien connus. Dans ce travail, deux voies de synthèse originales ont conduit à l'isolement de huit nouveaux analogues de BZP. Trois appartiennent aux séries benzo[c][1,9]phénanthrolin-6(5H)-one et pyridazino[4,5-c]phénanthrolin-6(5H)-one, deux à la série benzo[c][1,9]-phénanthrolinium et trois à la série benzo[c][1,9]phénanthroline et pyridazino[4,5-c]phénanthridine. <br />Une recherche de relation structure/activité quantitative (RSAQ/2D) a été menée. L'équation de RSAQ/2D a été construite à partir de 88 analogues de BZP possédant une activité antitopoisomérase en utilisant le logiciel MOE. Ces résultats sont exploités dans le cadre de la prédiction de cytotoxicité de nos nouvelles structures et pour orienter nos futurs travaux. Les valeurs prédictives montrent que l'activité biologique de ces composés dépend non seulement du groupement éthoxyle en position 12 mais également de la présence de deux atomes d'azote dans le cycle A.

Many exogenous and endogenous compounds are referred to as endocrine disruptors (EDCs), as they interfere with natural synthesis, signaling and metabolism of endogenous hormones. Common exogenous endocrine disruptors are benzo(a)pyrene (BaP) and 17α-ethinylestradiol (EE2). Endogenous endocrine disruptor 17β-estradiol (E2) is frequently present in the environment as well. In this thesis, the effect of the mentioned EDCs and their combinations on gene and protein expression of CYP1B1, 3A1 and 3A2 in rat liver, kidney and lung was determined. Protein expression was studied using Western blot method and specific antibodies; gene expression was assessed by quantitative PCR. Moreover, the effect of tested EDCs and their combinations on BaP metabolism and CYP3A specific activity (measured as testosterone 6β-hydroxylation) were studied in liver microsomal samples. It was confirmed, that BaP significantly increases CYP1B1 expression in rat liver and lung both alone and together with EE2 or E2. Pretreatment of rat with E2 and BaP increases the ability of BaP to induce CYP1B1 expression. On the contrary, EE2, E2 and their combination decrease the CYP1B1gene expression. The rate of BaP metabolites formed in liver microsomal samples increases in rats pretreated with BaP and its combinations. In liver, there was...

Depuis plusieurs décennies, la chimie du palladium a connu un véritable essor. Afin de de continuer dans cette optique, plusieurs axes de recherche ont été investigués dans le cadre de cette thèse. Grâce aux récents développements de la catalyse duale palladium/norbornène, la réaction de couplage entre des triflates aryliques et des partenaires bromobenzylamines nous a permis d’accéder à des motifs benzophénanthridines naturels. En parallèle, une nouvelle famille de complexes triangulaires de palladium a été isolée dans notre groupe. Cette espèce arborant 44 électrons de valence et une charge positive délocalisée sur son cœur tri-métallique, est la première molécule stable qui présente un caractère métallo-aromatique de type δ. Après l’optimisation d’une nouvelle voie de synthèse, nous avons pu accéder à des analogues de platine mais aussi à des composés hétéro-métalliques possédant des unités asymétriques similaires. Le caractère base de Lewis de ces complexes ont permis l’isolation de composés tétraédriques de type [M”(M₃)(Ln)]²⁺ malgré la répulsion des charges positives. Ces espèces triangulaires aromatiques ont aussi prouvé leur habileté en tant que catalyseur pour la réaction de semi-hydrogénation d’alcynes. En effet, ce complexe transforme chimiosélectivement les alcynes en alcènes de configuration Z sans présence de produit doublement réduit. / Recent developments on dual palladium/norbornene catalytic reactions led to one-pot synthesis of complexes polyheterocyclic molecules. By extension of this reaction, the coupling of aryl triflates and bromobenzylamines permitted us to synthesize natural benzophenanthridine. In parallel, a new family of triangular palladium complexes has been isolated in our research group. These 44 valence electrons complexes possessing a positive charge delocalized on the trimetallic core were the first stable compounds which presented δ-type aromaticity. After optimization of a new synthetic route, we could be able to isolate platinum analogues and also heterometallic clusters which interestingly had the same asymmetric unit than their homonuclear peers. Despite the unavoidable charge repulsion, the Lewis basic character revealed to be strong enough to bind other cationic species. Indeed, we reached to synthesize tetrahedral [M”(M₃)(Ln)]²⁺ complexes. In another side, we wondered if the stability and special properties of [Pd₃]⁺ clusters could confer to it some catalytic activities. Our studies were focused on semi-reduction reactions of alkynes. After optimization process, the catalyst [Pd₃(SMe)₃{P(C₇H)₃)₃}]⁺ showed results beyond our greatest expectations. Indeed, this cluster selectively produced thermodynamically less stable Z-alkene without traces of over-reduced compound. Total chemioselectivity towards alkynes was proved by the reaction on several molecules bearing functional groups which are sensitive to hydrogenation conditions.

ABSTRACT Cytochrome b5 (CYB5) is heme protein capable of reduction of cytochromes P450 (CYP) or some other enzymes. However, his regulative capability was also observed by his apo form, i.e. in absence of heme prosthetic group in the active center. CYB5 can accept electron from cytochrome b5 reductase (CYB5R) or from cytochrome P450 reductase (CYPOR). CYPOR by itself is reduced by NADPH and is also able to forward electron to CYP independently of CYB5. CYB5R on the other hand is reduced by NADH. Efficiency of CYB5 to accept and forward an electron was studied in vitro with five different substrates - testosterone, Sudan I, aristolochic acid I (AAI), ellipticine and vandetanib. These substrates were chosen considering their characteristic reactions, which are catalyzed by their respective isoforms of CYP. The experiments with these substrates were carried out in the medium with recombinant CYPs prepared in insect cells or E. coli or in the medium with hepatic microsomes isolated from different organisms. Rats, from which the majority of these microsomes was isolated, were premedicated by different CYP inducers. The experiments were carried out in medium with NADH or NADPH in order to assess the capability of CYB5 to reduce CYP independently of CYPOR. The capability of CYB5 and CYB5R to act as a...

Dans les zones humides, un déclin dramatique des populations d’amphibiens a été observé au niveau mondial depuis les années 80. Malgré de nombreuses études suggérant que les amphibiens sont très sensibles aux pressions anthropiques cumulées, le rôle joué par les perturbateurs endocriniens dans le déclin de leurs populations reste incertain. Parmi les perturbateurs endocriniens contaminants les zones humides, le benzo[a]pyrène (BaP) et le triclosan (TCS) sont couramment retrouvés. Au cours de ce travail, nous avons étudié la réponse physiologique de xénopes (Xenopus tropicalis) exposés à court terme (24 heures) et à long terme (du têtard à l’adulte mature) au BaP et au TCS à des concentrations réalistes d’un point de vue environnemental. En combinant une approche transcriptomique à haut débit et une caractérisation des modifications cellulaires et physiologiques, nous avons mis en évidence que le BaP, le TCS et leur mélange perturbent la physiologie globale du foie. Ce trouble est caractérisé par un phénotype semblable à de l’insulino-résistance et à une stéatopathie non alcoolique (NAFLD) associé à une hépatotoxicité médiée par une altération du métabolisme lipidique. Outre les effets directs sur le métabolisme des individus exposés, il apparaît que les perturbateurs endocriniens étudiés affectent également le succès reproducteur de ces individus et le développement de leur descendance. Prises dans leur ensemble, nos observations apportent ainsi des débuts de réponse quant aux rôles de la contamination chronique des milieux sur le déclin des populations d’amphibiens. / In wetlands, dramatic decline in amphibian populations have been described worldwide since the 80s. Despite numerous studies suggesting that amphibians are highly sensitive to cumulative anthropogenic stresses, the role played by endocrine disruptors in the decline of amphibian populations remains unclear. Among the endocrine disruptors contaminating wetlands, benzo[a]pyrene (BaP) and triclosan (TCS) are recurrently found. In this work, we studied the physiological response of Xenopus tropicalis exposed to environmentally realistic concentrations of BaP and TCS during a short-term (24 hours) and long-term (from tadpole to mature adult) period. By combining a high throughput transcriptomic approach and a characterization of cellular and physiological modifications, we showed that BaP, TCS and their mixture disrupt overall liver physiology highlighted by insulin resistance-like and non-alcoholic fatty liver disease (NAFLD)-like phenotypes together with hepatotoxicity due to the impairment of lipid metabolism. Additionally to direct metabolic impact observed on exposed individuals, the studied endocrine disruptors affected their fitness and their progeny development. Altogether, our observations bring new insights into the role plays by chronic contamination of wetlands on amphibian population decline.

Dans ce travail, de nombreux hétérocycles porteurs d’un groupement CF3 ou C2F5 ont été décrits : des cétals, des benzo[1,3]dixoles, des pyran-2H-ones, des isocoumarines, des benzofuranes et des indolo[2,3-c]pyran-1-ones. Ces hétérocycles représentent une classe importante de produits biologiquement actifs. L’hydroalkoxylation intermoléculaire des dérivés du 4,4,4-perfluorobut-2-ynoate d’éthyle en présence d’une quantité catalytique de sodium métallique dans des conditions simples et douces a permis la synthèse de cétals fluorés d’une manière totalement régiosélective. La méthodologie a été étendue par la suite aux dérivés phénols pour préparer ,dans un premier temps, stériosélectivement des éthers d’énols. Des benzofuranes fluorées ont été synthétisées par la suite par cyclisation de quelques éthers vinyliques dans les conditions de Heck. Dans les mêmes conditions et en utilisant des dérivés du catéchol, nous avons réalisé des synthèses totalement régiosélective des hétérocycles de type : benzo[1,3]dioxoles, benzo[1,3]oxazoles et benzo[1,3]oxothiazoles. l’hydrocarboxylation du 4,4,4-perfluorobut-2-ynoate d’éthyle en utilisant des dérivés de l’acide 2-iodobenzoïque suivi d’une cyclisation intramoléculaire de manière ‟one-potˮ utilisant des sels de cuivres (II) nous a permis d’accéder régiosélectivement aux isocoumarines porteuses d’un groupement fluoroalkyle. Cette réaction a été étendue par la suite à la série hétéroaromatique faisant appel aux dérivés indoliques porteurs d’une fonction acide en positions 2 et d’un atome d’iode en position 3. Cette approche a permis de synthétiser de nouveaux hétérocycles fluorés à savoir des indolo[2,3-c]pyran-1ones. Nous avons exploité aussi une partie de potentiel offert par les structures énynoates synthétisées pour synthétiser des pyran-2H-ones originales porteuses d’un groupement fluoroalkyle par une stratégie d’iodolactonisation. Les réactions du couplage de type Sonogashira ont permis la synthèse d’une diversité d’alpha pyrones. / Fluorinated heterocyclic compounds can be found among potent pharmaceuticals,crop protection agents, and products of technical importance. This mergingarea of organic, heterocyclic, and fluoroorganic chemistry is still rapidly growing andin the past decades a large number of fluorinated heterocyclic materials have been discovered. In this work, an efficient and original method was developed for the synthesis of 3,3-dialkoxy propionate bearing a perfluoroalkyl group in b-position from fluorinated alkyne and alcohols using base-catalyzed double Michael addition reaction. This method provides easy access to a-perfluoro ketals with reasonable to good yields with total regioselectivity. This procedure was extended to the phenol derivatives, and a fluorinated enol ether derivatives were selectively synthesized. The use of catechol and derivative allowed the synthesis of fluorinated heterocycles such as benzo[1,3]dioxoles, benzo[1,3]oxazoles and benzo[1,3]oxothiazoles. Copper-catalyzed annulation of aromatic and heteroaromatic b-iodo-a,b-unsaturated carboxylic acids with fluorinated alkyne 1 was developed. This strategy offers a simple and efficient route for the synthesis of isocoumarins and indolo[2,3-c]pyrane-1-ones. This family of compounds are known to have various biological properties; indolo[2,3-c]pyrane-1-one derivatives exhibit anti-cancer potential towards human cervix adenocarcinoma and antinociceptive and anti-inflammatory activity. Fluorinated pyrane-2H-ones bearing an iodine atom in position 5 have been also described. The a-pyrones constitute an important class of biologically active compounds.

L'obésité est une maladie définie par une accumulation de masse grasse dans le tissu adipeux ayant des conséquences néfastes pour la santé. Les causes de l’obésité sont multiples. Dans un travail récent, il y a été démontré le rôle de la pollution environnementale dans la prise de poids. Dans ce travail, les hypothèses selon lesquelles les récepteurs adrénergiques situés à la surface des cellules adipeuses seraient le siège de l’action des polluants aromatiques polycycliques ont été vérifiées par le dosage de plusieurs agonistes et antagonistes spécifiques et non spécifiques en présence ou non du benzo[a]pyrène sur des récepteurs humains et de cellules d’hamster chinois (CHO). Les quantités d’AMPc obtenues montrent que les HAP ne se déposent pas sur les récepteurs β1, β2, β3 adrénergiques.Cette accumulation se fait au niveau des phospholipides de la membrane cytoplasmique des cellules. Ce qui cause une rigidité des membranes.Cette observation tend à renforcer l'hypothèse selon laquelle le benzo[a]pyrène induirait une inhibition de la lipolyse par l'accumulation au niveau de la bicouche de phospholipides et des changements de conformation de la bicouche de phospholipides dans les environs des récepteurs à sept domaines transmembranaires qui sont β-adrénergiques.La liaison de la bicouche phospholipidique avec les HAP utilisés est une réaction exothermi-que avec un faible dégagement de chaleur / Obesity is a disease defined by an accumulation of fat in adipose tissue with adverse consequences for health. The causes of obesity are many.In recent work, there was demonstrated the role of environmental pollution in weight gain.In this work, the assumptions that the adrenergic receptors on the surface of fat cells would home to the accumulation of polycyclic aromatic pollutants have been verified by measurement of several agonists and antagonists specific and non-specific in the presence or absence of benzo[a]pyrene receptors on human cells and Chinese hamster (CHO). The amounts of cAMP obtained showed that PAHs are not deposited on β-receptors, β1, β2, β3 adrenergic receptors.This accumulation occurs at the cytoplasmic membrane phospholipids of the cells. What cau-ses stiffness of the membranes. This observation tends to reinforce the hypothesis that benzo [a]pyrene induce an inhibition of lipolysis by the accumulation in the phospholipid bilayer and conformational changes of the bilayer phospholipids in the vicinity of receptors seven transmembrane domains which are β-adrenergic receptors