987 resultados para Routes


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Contient : « Testament du feu mareschal de Biron, du 30 juillet 1602 » ; « Discours au vray du differend advenu entre le comte de Soissons et le sieur de Rosny ès mois d'aoust et autres 1603 » ; Ordonnance de Henri IV concernant la levée des impôts en Guyenne, 5 nov. 1603 ; « Mémoire instructif sur les payements faits des mil escus prestés à Mrs de Nemours et Senecey pour les affaires du pays de Bourgogne, » 1606-1608 ; « Accord des sieurs d'Emendreville et de Bourgneuf, » 22 janv. 1613 ; « Advis sur la querelle de messieurs le comte de Braine et le marquis de Nesle, » 1613 ; « Articles accordez par le sr duc de Vantadour... à Mr le prince de Condé..., » 15 mai 1614 ; Pièces concernant le différend entre les habitants de Baygorri et de Valderro (Navarre), 1615-1616, et 1656-1665 ; Traité entre l'empereur Matthias Ier et Sigismond III, roi de Pologne, 1615 ; « Satisfaction faite à M. le Mis de Coeuvres, ambassadeur pour le Roy à Home, 1619... » ; « Sommation faicte... à Mr de Soubize, estant dans la ville de St-Jean-d'Angeli, à ce qu'il eust à ouvrir les portes de la dicte ville au Roy, » juin 1621 ; « Articles de paix... entre le roy de France et l'empereur de Marocque..., le 3 septembre 1630 » ; Lettres de Christian IV, roi de Danemark, a Louis XIII et au cardinal de Richelieu, 24 mai 1627 ; « Ordres du roy au parlement de Dijon... pour travailler aux procez des ducs et pairs..., » 6 juillet 1632 ; « Traité de paix entre le roy de Polongne et le grand-duc de Moscovie, faict l'an 1634 » ; « Traité entre le roy de Pologne et l'électeur de Brandebourg, » 1638 ; « Traicté de ligue offensive et deffensive contre les Espagnols entre le roy Louis XIII et sa soeur la duchesse de Savoye, » 3 juin 1638 ; Autre, du 1er juin 1639 ; Déclaration du roi touchant les privilèges du Parlement, 19 août 1644 ; « Ratification du traicté faict avec le sr duc de Curland, l'an 1645 » ; « La vraye relation du tumulte arrivé en la ville de Mosco, capitale de la Moscovie, le 12 juin 1648. » — « Traicté entre Louis XIV... et les États generaux des Provinces Unies des Pays-Bas, » 29 juillet 1649 ; Sauf-conduit, au nom du prince de Conti, pour le sr Belot de la Hoche, 18 févr. 1649 ; « Remontrance au roi par le parlement de Toulouze au sujet de la dixiesme roïalle, » 1649 (?) ; « Requeste de la noblesse au Roy concernant les tabouretz, » 1649 (?) ; « Déclaration du Roy pour arrester tous ceux qui passeront sans aveu, » 22 avril 1650 ; « Convocation des manans et habitans de... Rouvray, au palais royal d'Auxerre, » pour élire des députés aux États généraux, 1651 ; « Articuli paris et amicitiæ inter... Protectorem Angliæ et Christianissimum Regem Gallorum, 1654 » ; « Extraict d'une lettre d'Angleterre, du 20 (et 22) aoust 1657 » ; « Projet d'instruction pour M. de Thou, ambassadeur en Hollande, 1657 » ; « Testament de feu M. le cardinal Mazarin, » 3 mars 1661 ; Signification au Parlement du traité conclu par Louis XIV avec le duc de Lorraine, 8 févr. 1662 ; Dernières paroles du maréchal de Fabert, 16 mai 1662 ; « Traitté de commerce entre la France et le Danemark, 1663, » et liste de différents traités conclus avec des puissances étrangères ; « Articles secrets du traité entre la France et le Danemarc,... 3 aoust 1663 » ; « Lettre du frère Fulgence de la Barthe, recolé... à M. le Mis de Coeuvres, » 29 oct. 1663 ; Marché de pourvoirie (viande et poisson) pour la table de la duchesse de Nemours à Paris, 1667 ; « Traité de paix entre les habitans des vallées d'Ossau et de Thènes, des années 1676, 80 et 83 » ; « Journal succinct du voiage du vaisseau la Marie, party du fort Dauphin, le 9e fevrier 1671, et arrivé au Port-Louis, le 22e juillet... 1671 » ; Lettre de MM. des Provinces Unies à Louis XIV ; La Haye, 10 déc. 1671 ; « Mémoire de M. le baron d'Isola touchant la restitution de Rhymberg, janvier 1672 » ; « Mémoire pour les affaires de Querci envoyé à M. des Brières, le 13 juillet 1673, par le sr Duchesne » ; Ordre de Louvois relatif aux dépenses des fortifications, 1680 ; « Estat de la dépense... pour les appointements des ambassadeurs » de France, en 1681 ; « Estat des dispenses expédiées en conséquence de la déclaration du mois de febvrier 1683... pour estre receus aux offices » ; « Lettres de naturalité de M. le duc de Richemont, » 1685 ; « Déclaration de Jacques, duc de Momouth,... pour délivrer le royaume [d'Angleterre]... de Jacques, duc d'York, 28 juin 1685 » ; Lettres circulaires aux archevesques et evesques et aux intendants, concernant les nouveaux convertis, 1686, 1698 et 1699 ; « Lettres de naturalité en faveur du sr Primi, italien, » mai 1686 ; « Naturalité pour les srs de Sphonem frères, allemans, » juillet 1686 ; « Dispence de serment de fidelité pour M. l'evesque de Grenoble à cause de sa promotion au cardinalat..., 25 déc. 1686 ; « Relation de l'abjuration de Molinos en 1687 » ; « Lettre du Roy au roy d'Angleterre sur l'offre de sa médiation pour l'accommodement des differens avec le pape, 19 févr. 1688 ; « Règlement que le Roy veut estre executé pour la punition des femmes et filles d'une débauche publique et scandaleuse qui se pourront trouver dans la ville... de Marseille,... dans la maison des femmes et filles pénitentes du Reffuge sous le titre de S. Joseph... » ; « Permission de construire un jardin des plantes à Nantes, au lieu où estoit le Papegault, en faveur des apoliquailes de Nantes, » févr. 1688 ; « Mémoire touchant Piombino, escrit en mai 1688, par le comte d'Elci » ; « Lettre de Sa Majesté au Père Lioncourt, provincial des Jésuites de la province de Champagne, à Reims, » 29 oct. 1688 ; « Confirmation d'établissement du collège des Ecossois à Paris, » déc. 1688 ; Projet d'assassinat du roi de France par le P. Carlo Ambrosio, cordelier de Rome, nov. 1688 ; « Contract d'aliénation des 1.200.000 # de routes au denier dix-huit, sur les aides et gabelles, » 2 déc. 1689 ; « Marché pour la fourniture des masts de Lorraine, » 26 mars 1691 ; « Instruction adressée par ordre du Roy à Mrs les évesques et commissaires départis dans les provinces pour l'exécution de l'arrest du 20 de ce mois, 22 déc. 1693 ; « Manifeste de Guillaume II, roy d'Angleterre, pour servir d'ouverture à la paix publiée sur la fin de l'année 1693 » ; Lettre circulaire de M. de C[roissy] à Mrs les intendants, etc., concernant les nouveaux convertis, 1694 ; « Rolle des maisons destinées pour le logement de la compagnie des Cent Suisses de la garde ordinaire du corps du Roy pour la présente année 1694 » ; « Rolle des maisons destinées pour le logement de la compagnie des Cent Suisses..., » 1695 ; « Rolle des cinquante gentilshommes retenus pour composer la compagnie de l'arrière-ban de la Prevosté de Paris, » 1695-1697 ; « Protestation du roy d'Angleterre contre tout ce qui pourra estre fait à son préjudice dans le traité de paix, » 8 juin 1697 ; « Extrait du traité de paix fait à Risvych, le 20 septembre 1697 » ; « Extrait de la lettre du P. Du Val au P. Fleuriau, du Sonnar, le 15 fevrier 1699, et de plusieurs autres lettres concernant l'Éthiopie » 1698-1701 ; « Mémoire touchant le nommé Murat, prétendu ambassadeur du roi d'Éthiopie en France, » 1698 ; « Plein pouvoir à M. le comte de Brionne, » pour conduire en France la princesse Marie-Adelaïde, fille aînée du duc de Savoie, pour être mariée au duc de Bourgogne, 10 sept. 1696

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The present studies describe, as a primary goal, our recent progess toward the synthesis of morphine alkaloids from aromatic precursors. Model substrates were synthesized which allowed investigation into Diels-Alder, radical cascade, and palladium-catalyzed bond-forming reactions as possible routes to the morphine alkaloid skeleton. As a secondary objective, three separate series of aromatic substrates were subjected to whole-cell oxidation with Escherichia coli JM 109 (pDTG601), a recombinant organism over-expressing the enzyme toluene dioxygenase. Included in this study were bromothioanisoles, dibromobenzenes, and cyclopropylbenzene derivatives. The products of oxidation were characterized by chemical conversion to known intermediates. The synthetic utility of one of these bacterial metabolites, derived from oxidation of o-dibromobenezene, was demonstrated by chemical conversion to (-)conduritol E.

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The mechanism whereby cytochrome £ oxidase catalyses elec-. tron transfer from cytochrome £ to oxygen remains an unsolved problem. Polarographic and spectrophotometric activity measurements of purified, particulate and soluble forms of beef heart mitochondrial cytochrome c oxidase presented in this thesis confirm the following characteristics of the steady-state kinetics with respect to cytochrome £: (1) oxidation of ferrocytochrome c is first order under all conditions. -(2) The relationship between sustrate concentration and velocity is of the Michaelis-Menten type over a limited range of substrate. concentrations at high ionic strength. (3) ~he reaction rate is independent from oxygen concentration until very low levels of oxygen. (4) "Biphasic" kinetic plots of enzyme activity as a function of substrate concentration are found when the range of cytochrome c concentrations is extended; the biphasicity ~ is more apparent in low ionic strength buffer. These results imply two binding sites for cytochrome £ on the oxidase; one of high affinity and one of low affinity with Km values of 1.0 pM and 3.0 pM, respectively, under low ionic strength conditions. (5) Inhibition of the enzymic rate by azide is non-c~mpetitive with respect to cytochrome £ under all conditions indicating an internal electron transfer step, and not binding or dissociation of £ from the enzyme is rate limiting. The "tight" binding of cytochrome '£ to cytochrome c oxidase is confirmed in column chromatographic experiments. The complex has a cytochrome £:oxidase ratio of 1.0 and is dissociated in media of high ionic strength. Stopped-flow spectrophotometric studies of the reduction of equimolar mixtures and complexes of cytochrome c and the oxidase were initiated in an attempt to assess the functional relevance of such a complex. Two alternative routes -for reduction of the oxidase, under conditions where the predominant species is the £ - aa3 complex, are postulated; (i) electron transfer via tightly bound cytochrome £, (ii) electron transfer via a small population of free cytochrome c interacting at the "loose" binding site implied from kinetic studies. It is impossible to conclude, based on the results obtained, which path is responsible for the reduction of cytochrome a. The rate of reduction by various reductants of free cytochrome £ in high and low ionic strength and of cytochrome £ electrostatically bound to cytochrome oxidase was investigated. Ascorbate, a negatively charged reagent, reduces free cytochrome £ with a rate constant dependent on ionic strength, whereas neutral reagents TMPD and DAD were relatively unaffected by ionic strength in their reduction of cytochrome c. The zwitterion cysteine behaved similarly to uncharged reductants DAD and TI~PD in exhibiting only a marginal response to ionic strength. Ascorbate reduces bound cytochrome £ only slowly, but DAD and TMPD reduce bound cytochrome £ rapidly. Reduction of cytochrome £ by DAD and TMPD in the £ - aa3 complex was enhanced lO-fold over DAD reduction of free £ and 4-fold over TMPD reduction of free c. Thus, the importance of ionic strength on the reactivity of cytochrome £ was observed with the general conclusion being that on the cytochrome £ molecule areas for anion (ie. phosphate) binding, ascorbate reduction and complexation to the oxidase overlap. The increased reducibility for bound cytochrome £ by reductants DAD and TMPD supports a suggested conformational change of electrostatically bound c compare.d to free .£. In addition, analysis of electron distribution between cytochromes £ and a in the complex suggest that the midpotential of cytochrome ~ changes with the redox state of the oxidase. Such evidence supports models of the oxidase which suggest interactions within the enzyme (or c - enzyme complex) result in altered midpoint potentials of the redox centers.

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The sequential banding patterns of the larval salivary gland polytene chromosomes of seven species of Inseliellum (Diptera: Simuliidae) were mapped. This was completed through the comparison with the standard maps of an eighth species of Inseliellum, Simulium cataractarum. During chromosomal analysis, both fixed and floating inversions were identified. A floating inversion (IIL-l ex,2ex) revealed a cytotype within Simulium exasperans that is distributed between two islands, Moorea and Tahiti. Inversion data revealed three shared fixed inversions that could be used as phylogenetic characters. In addition, the placement of a chromosomal landmark (the nucleolar organizer, or NO) was used as a phylogenetic character. The result of a cytophylogenetic (transformational) analysis showed two groups: the NO-IL group, and the NO-IS group. A combined phylogeny was created using the published morphological data and the cytological data of the eight species. The combined tree did not differ from the morphological data only tree. Possible routes of dispersal are hypothesized using geological, chromosomal, and phylogenetic data. These data showed a general pattern of dispersal and colonization from older islands to younger islands, with one possible instance of dispersal from younger to older islands. It is postulated that inter-island speciation has allowed this dispersal and colonization, but intra-island speciation has created the diversity seen in Inseliellum.

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1-(0- and m-Ohlorobenzoyl)isoquinolines have been synthesized by two routes involving Reissert compounds. One route involves condensation of 2-benzoyl-l,2-dihydroisoquinaldonitrile with the appropriate chlorobenzaldehyde and the second involves rearrangement of the appropriate Z-(chlorobenzoyl)-l,Z-dihydroisoquinaldonitrile under basic conditions. The action of potassamide in anhydrous liquid ammonia on both ketones gave unexpectedly N-(l-isoquinolyl)benzamide (67) as the major product and the use of dibenzo-18-crown-6-ether 98% substantially improved the yd..e.ld in the case of l-chloroketone. This amide (67) exhibits unusual hydrogen bonding. 1-(o-chlorobenzoyl)-6,7-dimethoxyisoquinoline (79) was prepared in very s,amll quantities by the route involving condensation of 2-benzoyll, Z-dihydro-6,7-dimethoxyisoquinaldonitrile with o-chlorobenzaldehyde. The poor yields are due to the instability of the anion of 2-benzoyl1, Z-dihydro-6,7-dimethoxyisoquinaldonitrile. Attempted preparation of the ketone (79) by rearrangement of 2-(o-chlorobenzoyl)-l,2-dihydro6,7- dimethoxyisoquinaldonitrile under basic conditions yielded the start~ng material (Reissert compound) and 6,7-dimethoxyisoquinoline. The action of potassamide in anhydrous liquid ammonia on l-(o-bromo-4,5-dimethoxybenzoyl)isoquinoline (85), which was prepared by the route involving the condensation of 2-benzoyl-l,4-dihydroisoquinaldonitrile with o-bromo-4,5-dimethoxybenzaldehyde, gave two products, which have not yet been identified. The ketone (85) and its precursors are interest~ng in that their 20 eV and 70 eV mass spectra do not show molecular ions.

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The work described in t his thesis was initiated with the intention of exploring new routes for the synthesis of certain 4, 5-disubstituted phenanthrenes. A series of reactions have been investigated in detail and several 4, 5-disubstituted phenanthrenes have been prepared. Some of the methods employed were novel and the yields of products were comparable or even better than the existing routes . A major observation made during the course of this work was the stability of the seven-membered ring system bridging the 4 and 5 positions of the phenanthrene nucleus . It has been found t hat the unbridged structures are not preferred if the compound is capable of isomerising to a bridged form . We have explained this phenomenon in t erms of the stereochemistry of t he 4 and 5 positions of the phenanthrene nucleus as well as the geometry of the bridge . Low temperature NMR studies have been carried out to investigate the conformations of the benzylic hydrogens of some of the 4,5-bridged compounds. However, the results were not conclusive as more than one reason could be attributed t o the observations .

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This research was directed towards the investigation of the Smiles rearrangement in hydrazidic systems and the synthesis of related heterocyclic compounds. The work can be conveniently divided into two main sections. Section 1 of the thesis relates to the synthesis and examination of the O+N migration of phenoxy- derivatives of hydrazidic halides. In general, hydrazidic halides were found to react with 2-nitrophenol and 4-nitrophenol to give corresponding a-nitrophenoxy- compounds. These a-nitrophenoxy- compounds were found to rearrange in warm base to give the corresponding N-benzoyl compounds via a proposed five-membered transition state. Experiments conducted in styrene revealed no radical contribution to the rearrangement. Cross-over product analysis indicated the rearrangement as intramolecular and consistent with the Smiles rearrangement. The preparation of N-a-chlorobenzylidene-N'-2-nitrophenyl- -N'-(2,4-dibromophenyl)hydrazine from N-benzoyl-N'-2-nitrophenyl- N'-(2,4-dibromophenyl)hydrazine was accomplished using phosphorus oxychloride. Examination of this hydrazidic chloride indicated a marked decrease .in reactivity as compared to the N-a-chlorobenzylidene-N'-phenylhydrazine case. Section 2 concerns itself with the preparation of heterocyclic compounds using an analogy of the five-membered transition state present in the Smiles rearrangement of a substituted benzylidene derivatives A new preparation of 2,4-phenyl1,3,4- oxadiazol-S-one using N-benzoyl-N'-phenylhydrazine and ethyl thiochloroformate is reported. Two new preparations of N-a-thiobenzoyl-N'-(2,4-dibromophenylhydrazine are reported using sodium hydrosulfide in conjunction with N-a-bromobenzylidene-N'-(2,4-dibromophenyl)hydrazine in the first, and phosphorus pentasulfide with N-benzoylN'-( 2,4-dibromophenyl)hydrazine in the second. The latter is preferred due to the formation of a sulfide co-product in the former. Two preparations of 2-phenyl-4-(2,4-dibromophenyl)-1,3,4- thiadiazol-S-one are reported using N-thiobenzoyl-N'-(2,4-dibromophenyl) hydrazine and ethyl chloroformate and ethyl thiochloroformate Two rapid and easy preparations of 2-phenyl-4-(2,4-dibromophenyl)- 1,3,4-triazol-S-one are reported using ethyl chloroformate and ethyl thiochloroformate. Sodium cyanate in conjunction with a-aminobenzylidene-N'-(2,4-dibromophenyl)hydrazine also provided 2-phenyl-4-(2,4-dibromophenyl)-1,3,4-triazol-S-one Section 2 concludes with an examination of two possible mechanistic routes to the prepared heterocycles.

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Reactions of 5,6- and 4,5-epoxycholestane derivatives with strong bases were investigated. Epoxidation of 3a-acetoxycholest-5-ene also gave a new compound along with the anticipated epoxides. Interconversions of the latter were observed. Some possible mechanisms of its formation and rearrangements have been pIioposed. No reaction was observed with any of the 5,6- and 4,5-steroidal epoxides employed in the present study, using potassium tertiary butoxide under refluxing conditions. n-Butyllithium reacted only with 5,6-epoxycholestanes bearing a ketal moiety at the C3 carbon. Opening of the ketal group was observed with n-butyllithium in the case of a ~-epoxide. The reaction was also investigated in the absence of epoxide functionality. A possible mechanism for the opening of ketal group has been proposed. Lithium diethylamide (LDEA) was found effective in rearranging 5,6- and 4,5-epoxides to their ~orresponding allylic alcohols. These rearrangements presumably proceed via syn-eliminations, however the possibility of a corresponding anti-elimination has not been eliminated. A substituent effect of various functional groups (R = H, OH, OCH2CH20) at C3 has-been observed on product distribution in the LDEApromoted rearrangements of the corresponding epoxides. No reaction of these epoxides was observed with lithium diisopropylamide (LDA) • In the second part of the project, several attempts were made towards the sYRthesis of deoxycorticoste~one~17,2l,2l~d3' a compound desirable for the 2l-dehydroxylation studies of deoxycorticosterone. Several routes were investigated, and some deuterium labelled pregnane derivatives were prepared in this regard. Microbial 21-hydroxylation of progesteronel7,21,21,2l- d4 by ~ niger led to loss of deuterium from C21 of the product. An effort was made to hydroxylate progesterone microbially under neutral condtions.

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Compounds containing the pyrrolidine moiety are key substructures of compounds with biological activity and organocatalysts. In particular, annulated chiral pyrrolidines with alpha stereogenic centers have aldostereone synthase inhibition activity. In addition, 5-substituted pyrroloimidazol(in)ium salts precursors to N-heterocyclic carbene (NHC) precatalysts are rare due to a lack of convenient synthetic routes to access them. In this thesis is described a rapid synthesis of NHC precursors and a possible route to 5-substituted pyrroloimidazole biologically active compounds. The method involves the preparation of chiral saturated and achiral unsaturated pyrrolo[I,2- c]imidazol-3-ones from N-Cbz-protected t-Butyl proline carboxamide. The resulting starting materials may be used to prepare the target chiral annulated imidazol(in)ium products by a two-step sequence involving first stereoselective lithiation-substitution, followed by POCh induced salt formation.

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The site of present-day St. Catharines was settled by 3000 United Empire Loyalists at the end of the 18th century. From 1790, the settlement (then known as "The Twelve") grew as an agricultural community. St. Catharines was once referred to Shipman's Corners after Paul Shipman, owner of a tavern that was an important stagecoach transfer point. In 1815, leading businessman William Hamilton Merritt abandoned his wharf at Queenston and set up another at Shipman's Corners. He became involved in the construction and operation of several lumber and gristmills along Twelve Mile Creek. Shipman's Corners soon became the principal milling site of the eastern Niagara Peninsula. At about the same time, Merritt began to develop the salt springs that were discovered along the river which subsequently gave the village a reputation as a health resort. By this time St. Catharines was the official name of the village; the origin of the name remains obscure, but is thought to be named after Catharine Askin Robertson Hamilton, wife of the Hon. Robert Hamilton, a prominent businessman. Merritt devised a canal scheme from Lake Erie to Lake Ontario that would provide a more reliable water supply for the mills while at the same time function as a canal. He formed the Welland Canal Company, and construction took place from 1824 to 1829. The canal and the mills made St. Catharines the most important industrial centre in Niagara. By 1845, St. Catharines was incorporated as a town, with the town limits extending in 1854. Administrative and political functions were added to St. Catharines in 1862 when it became the county seat of Lincoln. In 1871, construction began on the third Welland Canal, which attracted additional population to the town. As a consequence of continual growth, the town limits were again extended. St. Catharines attained city status in 1876 with its larger population and area. Manufacturing became increasingly important in St. Catharines in the early 1900s with the abundance of hydro-electric power, and its location on important land and water routes. The large increase in population after the 1900s was mainly due to the continued industrialization and urbanization of the northern part of the city and the related expansion of business activity. The fourth Welland Canal was opened in 1932 as the third canal could no longer accommodate the larger ships. The post war years and the automobile brought great change to the urban form of St. Catharines. St. Catharines began to spread its boundaries in all directions with land being added five times during the 1950s. The Town of Merritton, Village of Port Dalhousie and Grantham Township were all incorporated as part of St. Catharines in 1961. In 1970 the Province of Ontario implemented a regional approach to deal with such issues as planning, pollution, transportation and services. As a result, Louth Township on the west side of the city was amalgamated, extending the city's boundary to Fifteen Mile Creek. With its current population of 131,989, St. Catharines has become the dominant centre of the Niagara region. Source: City of St. Catharines website http://www.stcatharines.ca/en/governin/HistoryOfTheCity.asp (January 27, 2011)

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This thesis explored the development of several methodologies for the stereoselective construction of ligand frameworks and some of their applications. The first segment concerns the application of an enantioselective lithiation at an Sp3_ hybridized position adjacent to nitrogen by means of the widely used and typically highly effective enantioselective lithiation with ( -)-sparteine. This investigation was intended to develop a method to install chirality into a system that would be converted into a family of diaminoylidenes for use as phosphine mimics in transition metal catalysis or as nucleophilic reagents. Molecular modeling of the system revealed some key interactions between the substrate and (-)-sparteine that provided general insight into the diamine's mode of action and should lend some predictive value to its future applications. The second portion focuses on the development of methods to access 1,2- disubstituted aminoferrocenes, an underexplored class of metallocenes possessing planar chirality. Two routes were examined involving a diastereoselective and an enantioselective pathway, where the latter method made use of the first BF3-mediated lithiation-substitution to install planar chirality. Key derivatives such as 1,2- aminophosphines, made readily accessible by the new route, were evaluated as ligands for Pd(II), Pt(II) and Ir(I). These complexes show activity in a number of transformations with both achiral and prochiral substrates. Optimization experiments were conducted to prepare enantiomerically enriched 2-substituted-I-aminoferrocenes by direct asymmetric lithiation of BF3-coordinated tertiary aminoferrocenes. A predictive computational model describing the transition state of this reaction was developed in collaboration with Professor Travis Dudding's group (Department of Chemistry, Brock University). The predicted stereochemistry of the process was confirmed by single-crystal X-ray analysis of a 2-phosphino-l-dimethylaminoferrocene derivative. Enantiomerically pure samples of the aminophosphine ligands derived from this new process have given promising preliminary results in the enantioselective hydrogenation of prochiral alkenes and warrant further stUdy in metal-mediated catalysis.

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The present studies describe our recent progress in target oriented synthesis of complex organic molecules from aromatic precursors. The latest synthetic approaches toward vinca alkaloids are described and include the construction of model substrates for the investigation into Diels-Alder, radical cascade, and tandem Michael addition reactions as possible routes to the family of alkaloids. Also described are the chemoenzymatic syntheses of the natural product (-)-idesolide and unnatural polyhydroxylated pyrrolidines generated from the biotransformation of benzoic acid with Ralstonia eutropha B9.

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Affiliation: Pascal Michel : Département de pathologie et microbiologie, Faculté de médecine vétérinaire

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La contribution de l’inhalation et de la voie percutanée à l’exposition totale à des composés organiques volatils (COV) présents dans l’eau potable est une problématique qui suscite un intérêt grandissant en santé publique et au niveau réglementaire. Jusqu’à tout récemment, seule l’ingestion était considérée dans l’évaluation du risque des contaminants de l’eau. L’objectif de ce projet était de caractériser l’impact de l’exposition multivoie sur la pharmacocinétique et la dose interne de trois COV : le toluène (TOL), le n-hexane (HEX) et le cyclohexane (CYCLO). À cette fin, un modèle expérimental animal a été utilisé et un modèle toxicocinétique à base physiologique (TCBP) a été adapté pour le TOL. Des rats Sprague-Dawley ont été exposés par voies uniques (inhalation, orale et percutanée) ou simultanées (multivoie) aux solvants. Pour le TOL, les trois voies ont été expérimentées, alors que la voie percutanée n’a pas été retenue pour le HEX et le CYCLO. Des prélèvements sanguins ont permis de caractériser les cinétiques sanguines. Les niveaux sanguins, obtenus lors des expositions multivoies, étaient généralement plus élevés que la somme des niveaux associés aux expositions par voies uniques, fait illustré par le rapport des surfaces sous la courbe expérimentale versus les prédictions (TOL : 1,30 et 2,19 ; HEX : 1,55 ; CYCLO : 0,98 et 0,99). Le modèle TCBP prédit bien la cinétique du TOL lors d’expositions par voies uniques et par multivoies. Les données expérimentales obtenues suggèrent que la dose interne résultant d’une exposition multivoie ne peut pas toujours être prédite par la somme des doses internes obtenues lors d’expositions par voies uniques. Ce phénomène serait explicable par la saturation du métabolisme. La modélisation TCBP est un outil efficace pour l’estimation du risque relatif à l’exposition multivoie aux COV présents dans l’eau potable.