Dissertations / Theses on the topic 'Porphyrio'

Meso-hydroxyuroporphyrin I, B-hydroxypropionic acid uroporphyrin I, hydroxyacetic acid uroporphyrin I and peroxyacetic acid uroporphyrin I have been isolated from the urine and plasma of patients with congenital erythropoietic porphyria (CEP) by high-performance liquid chromatography and characterized by liquid secondary ion mass spectrometry and chemical properties. The physico-chemical properties of these compounds have been studied. The hydroxy- and peroxyacetic acid- uroporphyrin I derivatives are the true metabolites of uroporphyrinogen I in vivo and their presence in urine and plasma is a common feature of CEP. The absence of these derivatives in duodenal aspirate and faeces suggests that they are of erythropoietic origin. The mechanism of formation of the hydroxy- and peroxyacetic acid- uroporphyrin I has been investigated. Peroxyacetic acid uroporphyrin I is formed from uroporphyrinogen I in the presence of H202 and iron while the hydroxylated uroporphyrin I derivatives are most probably produced by hydroxyl radicals generated during the formation of peroxyacetic acid uroporphyrin I. Destruction of porphyrins is found in the same reaction and can be prevented bydesferrioxamine, indicating that it is due to hydroxyl radicals. The formation of peroxyacetic acid- and hydroxyuroporphyrin I derivatives are uroporphyrinogen I concentration dependent. These derivatives can only be formed when uroporphyrinogen I is accumulated to a certain concentration (approx. 1-2 ~M) and the formation is then proportional to the uroporphyrinogen I concentration. The peroxylation reaction has been shown to take place only at the acetic acid side-chains of porphyrinogen and not at the propionic acid side-chains. The peroxylation reaction can therefore take place whenever a porphyrinogen with an acetic acid substituent is accumulated. Oral charcoal therapy failed to reduce the porphyrins accumulated in vivo in a patient with CEP. Uroporphyrin I, the major porphyrin accumulating in CEP, was not excreted into bile and interruption of the enterohepatic circulation by binding porphyrins onto charcoal therefore does not benefit CEP. It may, however, be effective in the treatment of hepatic porphyrias in which the accumulated porphyrins are mainly excreted via the gut lumen.

Les composés polymacrocycliques présentent un grand intérêt grâce à leurs caractéristiques remarquables de coordination. Pour la première fois, l’approche synthétique fonctionnelle aux diverses composés bi- et polycycliques contenant plusieurs fragments d’éthers aza-couronnes, aux cryptands et aux supercryptands à base d’éthers aza-couronnes a été élaborée par Krakowiak et ses collaborateurs au début des années 1990, par l’usage de simples réactions de substitution nucléophile. Actuellement, les composés hétéropolymorphes polymacrocycliques, capables de former des complexes polynucléaires avec différents métaux présentent le plus grand intérêt. Dans la grande majorité des travaux la synthèse de presque toutes les composés polymacrocycliques a été réalisée à l’aide des méthodes non orthodoxes, à l’exception des molécules, composées de plusieurs macrocycles porphyriques (de la diade et de la triade), pour l’obtention desquelles ont été appliquées les réaction de Suzuki, le couplage de Sonogashira et la réaction de Heck. Le laboratoire de synthèse organominérale de la Faculté de chimie de l’Université d’Etat de Moscou a accumulé une riche expérience dans l’utilisation de l’amination pallado-catalysée pour la synthèse de diverses composés macrocycliques et polymacrocycliques, et, actuellement, on étudie activement l’arylation cupro-catalysée des di- et polyamines. À cet égard, l’étude de l’amination cupro-catalysée pour la synthèse de composés polymacrocycliques qui contiennent comme connecteurs des diamines et des polyamines a permis développer des méthodes de catalyse métallique et d’obtenir de nouveaux types de conjugués polytopiques et polymacrocycliques, qui comprennent dans leur composition structurelle des fragments éthers aza-couronnes, porphyrines et calixarènes, étudiés pour leur capacité à détecter des cations des métalliques.Le but de ces recherches est de développer des méthodes catalytiques de synthèse de conjugués polymacrocycliques qui contiennent dans leur composition structurale des fragments éthers aza-couronnes, des porphyrines et des calix[4]arènes et d’étudier leurs capacités à détecter des cations métalliques. Pour atteindre cet objectif, il est nécessaire de résoudre les problèmes suivants: 1) établir la généralité de l’amination catalysée par le Cu(I) des dérivés éthers aza-couronnes et des porphyrines contenant des halogènes et de synthétiser les dérivés aminés; 2) développer des méthodes de la macrocyclisation catalytique pour obtenir des composés macrobicycliques et macrotricycliques qui contiennent dans leur structure des fragments éthers diaza-couronnes, des tétraazamacrocycles ( cyclènes et cyclames) et des calix[4]arènes; 3) modifier les composés macrocycliques et macrobicycliques par des substituants fluorophores, y compris des porphyrines; 4) à l’aide de la spectroscopie UV et de la fluorescence, étudier la liaison cations métalliques-polymacrocycles et identifier les détecteurs potentiels moléculaires fluorescents et colorimétriques
Polymacrocyclic compounds are of great interest due to their unique coordination properties. The first convenient synthetic approach to various polycyclic compounds containing several azacrown-ether moieties, to cryptands and supercryptands, based on azacrown-ethers, has been developed by Krakowiak and coworkers in the beginning of 1990s using simple nucleophilic substitution reactions. At present time heteropolytopic polymacrocyclic compounds, capable of forming polynuclear complexes with various metals, attract the utmost interest. In the majority of publications dealing with the synthesis of polymacrocyclic compounds non-catalytic approaches were applied, except for several porphyrin dyads and triads, which were obtained using Suzuki, Sonogashira and Heck reactions. The laboratory of organoelement compounds of Chemistry Department of Lomonosov Moscow State University has a great experience of the application of Pd-catalyzed amination reactions for the synthesis of polymacrocyclic compounds, nowadays Cu-catalyzed arylation of di- and polyamines is under investigation. Bearing it in mind we have found the research for Cu-catalyzed amination to be important in synthesis of polymacrocyclic compounds containing di- and polyamine linkers; as well as the synthesis of new types of polytopic polymacrocyclic conjugates, bearing azacrown-ether, porphyrin and calixarene moieties, by means of Pd- and Cu-catalyzed reactions; and studying their properties as metal cations detectors.The aim of the research is to develop catalytic synthetic approaches to polymacrocyclic conjugates, bearing azacrown-ether, porphyrin and calix[4]arene moieties, and to study their abilities as detectors for metal cations. For this purpose it is necessary to carry out the following investigations: 1) to study the regularities of Cu(I)-catalyzed amination of halogen derivatives of azacrown-ethers and porphyrins and to synthesize corresponding amino derivatives; 2) to develop the methods for the catalytic macrocyclization aimed at the synthesis of macrobicyclic and macrotricyclic compounds, containing diazacrown-ether, cyclen, cyclam and calix[4]arene moieties; 3) to introduce fluorophoric fragments (including porphyrins) into macrocyclic and macrobicyclic compounds; 4) to investigate metal cations binding by thus synthesized polymacrocycles using UV and fluorescent spectroscopy, and to find possible fluorescent and colorimetric detectors among them

Twelve porphyrin dyads linked by an ethene bridge were synthesised as model systems for conjugated polymers. The extent of interporphyrin interaction was investigated for meso-meso and meso-β linked homo- and heterobimetallo-porphyrin dyads. To complement these dyads, model monomers with alkenyl substituents were also studied. Once the synthesis of these compounds was achieved, the extent of interaction was studied using UV-visible and fluorescence spectroscopy and molecular modelling. In order to gain a true indication of the extent of interaction in a dyad, the effect of the bridge as a substituent must be accounted for. This was achieved by studying the series of monomers by UV-visible and fluorescence spectroscopy. The increased conjugation resulting from mono- and bis-alkenyl substituents results in a red shift of the origin of transition energies in the absorption spectrum which is accompanied by a broadened and less intense Soret band and an increase in the intensity of the Q bands. The emission of these compounds also displays an increase in Stokes shift and a loss of vibronic coupling due to the increased conjugation. The serendipitous synthesis of three asymmetric meso-β ethene-linked porphyrin dyads was achieved by the use of palladium-catalysed Heck coupling of mesoethenyl- with meso-bromoporphyrins. A possible mechanism for this meso to β rearrangement was proposed. A series of nine meso-meso ethene-linked dyads was synthesised by palladium-catalysed Suzuki coupling of meso-(2-iodoethenyl)- with meso-borolanylporphyrins. All of these dyads were characterised by 1D and 2D NMR as well as MS analysis. The absorption spectra of ethene-linked dyads exhibit a split Soret band and a red-shifted and intensified HOMO-LUMO band. In the meso-β dyads, the degree of splitting in the Soret band is sufficient only to generate a shoulder on the red edge, whereas in the meso-meso dyads two separate bands appear. The extent of splitting is believed to be an indication of the amount of porphyrin-porphyrin interaction. The fluorescence profiles of the dyads change dramatically depending upon the central substituents in the porphyrins and the wavelength used for irradiation, which suggests that different conformations of these compounds give rise to different parts of their absorption and emission profiles. The fluorescence profiles of the dyads also do not reflect their absorption profiles, and therefore the excitation of the dyad is believed to be accompanied also by a change in geometry. All ethene-linked dyads exhibited an anti-Stokes shift, and the excitation spectra of the different parts of the fluorescence envelope also support the possibility of different conformers contributing to the fluorescence spectra. Molecular mechanics and time-dependent quantum mechanical calculations were performed on seven ethene-linked porphyrin dyads. These calculations further support the proposal of different conformations contributing to the physical properties of ethene-linked dyads. Electronic structure calculations also show considerable electron density on the alkene for the meso-meso ethene-linked dyads, which highlights the important influence of this bridge upon the electronic nature of these conjugated diporphyrins.

Résumé : Le travail de recherche présenté dans ce mémoire fut inspiré par le processus de la photosynthèse qui se produit chez les plantes. Au cours de ce processus l’énergie solaire est convertie en énergie chimique via différentes étapes de transferts d’électrons et d’énergie. En maîtrisant bien ces concepts, de nombreuses applications, telles que les cellules photovoltaïques ou les DEL (Diodes électro-luminescentes) peuvent être améliorées. Pour se faire, il est important d’optimiser les propriétés des matériaux existants (oligomères, polymères, etc…) en préparant des systèmes conjugués plus efficaces, mais aussi de pleinement comprendre les processus qui s’y produisent (processus de transferts d’électrons et d’énergie photo-induist). La série d’oligomères et de polymères présentée dans ce mémoire le sont pour leurs applications dans des systèmes photoniques. Dans cette optique, ce mémoire a été divisé en cinq grands chapitres. Le premier présente les principes théoriques de la photophysique. Le second présente le suivi du transfert d’énergie T[indice inférieur 1] dans les états triplets, T[indice inférieur 1], une dyade constituée de la tétraphénylporphyrine de zinc(II), [ZnTPP], et de la bis(phénylpyridinato)(bipyridine) d’iridium(III), [Ir], chromophores liés avec un pont trans-diéthynylbis(phosphine)-platine(II). Malgré que cette dyade soit entièrement conjuguée et qu’elle soit constituée d’un donneur ([ZnTPP]) et d’un accepteur ([Ir]), aucun transfert d’énergie T[indice inférieur 1] [Ir] → S[indice inférieur 1]/T[indice inférieur 1] [ZnTTP] n’a été observé. Ce résultat fut attribué à l’absence de recouvrement des orbitales moléculaires entre la HSOMO(donneur*) et la HSOMO(accepteur), LSOMO(accepteur) and LSOMO (donneur*) (mécanisme de Dexter). Ainsi, l’échange d’électrons est impossible. Ce chapitre suggère que l’équation de Dexter, k[indice inférieur Dexter] = KJexp(-2r[indice inférieur DA]/L) ne reste qu’une approximation. Ce travail a été publié dans ChemComm (2013, 49, 5544-5546). Le troisième chapitre présente le transfert d’énergie singulet beaucoup lent qu’attendu se produisant dans une dyade constituée d’une porphyrine de zinc(II) avec une porphyrine base libre liées par un pont palladium(II) (trans-PdI[indice inférieur 2]). Sachant que cette dyade est entièrement conjuguée et que la distance entre les deux centres de masse des porphyrines est relativement courte, ce système aurait dû présenter un transfert d’énergie très rapide, d’après la théorie de Förster. Dans ce cas, ce comportement a été expliqué par le faible recouvrement des orbitales frontières (OM) du donneur et de l’accepteur. Ce travail a été accepté le 2014-05-26 dans Chemistry – A European Journal (chem.201403146). Le quatrième chapitre rapporte une étude du transfert d’énergie ultra-rapide (650 fs) entre des états singulets dans une dyade composé d’une porphyrine de zinc(II) (le donneur) et une porphyrine base libre (l’accepteur) liées à l’aide d’un pont de palladium ([beta],[beta]--trans-Pd(NH)[indice inférieur 2](CO)[indice inférieur 2]). Ces résultats ont été attribués à la présence d’un couplage fort entre les OM du donneur et de l’accepteur et de la très faible contribution (atomique) du Pd(II) vers ces OM. Cette dyade montre la plus rapide constante de transfert d’énergie k[indice inférieur ET] que nous connaissons pour des dyades similaires contentant un fragment métallique. Les résultats du troisième et quatrième chapitre montrent que la théorie de Förster tel quel ne suffit pas pour prédire les vitesses de transferts d’énergie dans certains systèmes : d’autres facteurs doivent être pris en compte. Ce travail a été soumis dans JACS ( ja-2014-061774, 19-6-2014). Dans le cinquième chapitre de ce mémoire, la synthèse du bis(-[alpha]-(amino(4-éthynylbenzene (triméthylsilane)(R))))bis(4-éthynylbenzene-(triméthylsilane))quinone diimine (R= H, Boc) comme modèle pour des polymères conjugués et non-conjugués contenant le colorant porphyrine a été proposée. Le corps du composé désiré (tétrakis(4-éthynlyphenyl)quinone-1,4-diimine-2,5-diamine) a montré un transfert de charge partant des groupes terminaux riches en électrons une la benzoquinone centrale plus pauvre. La nature de l’émission fut observée uniquement à 77K pour le cas où R = H et fut attribuée à de la fluorescence. À température ambiante, l’intensité était trop faible pour être observée. Dans le cas où R = Boc, aucune emission n’a été détectée. Malheureusement, le composé espéré ne fut pas obtenu, le procédé de synthèse employé engendra uniquement la forme réduite. Cette forme fut malgré tous analysé, et ne présenta pas de transfert de charge ni de communication entre les différents chromophores. Ceci a été expliqué simplement par le fait que la conjugaison est brisée quand ce composé est sous sa forme réduite. Ce travail sera soumis au Journal of Inorganic and Organometallic Polymers and Materials. // Abstract : The research work presented in this master thesis is inspired by the photosynthetic process occurring in plants where solar energy is converted into chemical energy via several energy and electron transfer processes. In the light of these concepts, several applications such as solar cells and light emitting diodes can be improved. To do so, we need to optimize the properties of polyads, oligomers and polymers to device more efficient conjugated materials as well as developing a full understanding of the photo-induced energy and electron transfer processes that occur. Several organometallic oligomers and polymers are presented in this thesis due to their potential photonic applications. In this respect, this master thesis has five chapters. The first one introduces some theoritical principles of photophysics. The second one presents the monitoring of triplet state (T[subscript 1]) energy transfer in a dyad that consists of zinc(II)tetraphenylporphyrin, [ZnTPP], and bis(phenylpyridinato)-(bipyridine)iridium(III), [Ir], chromophores linked by a platinum(II) containing bridge. Despite the conjugation in this dyad and the presence of the [ZnTPP] energy donor and the [Ir] energy acceptor species, no T[subscript 1] [Ir] → S[subscript 1]/T[subscript 1] [ZnTTP] energy transfer occurs. This result was explained by the absence of MO overlap between HSOMO(donor*) and HSOMO(acceptor), LSOMO(donor*) and LSOMO(acceptor) , and hence no efficient double electron transfer exchange (i.e. Dexter mechanism) is likely to occur. This chapter suggested that Dexter formulation, k[subscript Dexter] = KJexp(-2r[subscript DA]/L), appears as an approximation. This work has been published in ChemComm (2013, 49, 5544-5546). The third chapter shows an unexpected slow singlet energy transfer in a dyad built upon a zinc(II)porphyrin and the corresponding free base chromophores linked by a palladium(II)- containing bridge (trans-PdI[subscript 2]), despite the presence of conjugation and the relative short center-to-center distance. This behavior was explained by two factors, the first is the lack of large molecular orbitals (MOs) overlaps between the frontier MOs of the donor and acceptor, and thus preventing a double electron exchange to occur through the trans-PdI[subscript 2] bridge. The second factor affected the energy transfer is the electronic shielding induced by the presence of this same linker, namely the electron rich iodides, preventing the two VI chromophores to fully interact via their transition dipoles. This work has been accepted on 2014-05-26 in Chemistry-A European Journal (chem.201403146). The fourth chapter reports an ultrafast singlet energy transfer (650 fs) in a dyad composed of a zinc(II)porphyrin (donor) and a free base porphyrin (acceptor) [beta],[beta]-linked via trans- Pd(NH)[subscript2](C=O)[subscript 2]. These results were explained by the presence of strong MO couplings of the donor and acceptor and the very weak atomic contribution of the Pd(II) atom to this MO. This dyad shows the fastest energy transfer rate k[subscript ET] among other similar dyad systems incorporating a bridge either in the form of a metal fragment or carbon-based. The results of these third and fourth chapters showed that the Förster mechanism is not enough to account for the energy transfer in some systems and other factors affect that transfer. This work has been submitted in JACS ( ja-2014-061774, 19-6-2014). In chapter 5, the synthesis of bis-[alpha]-(amino(4-ethynylbenzene (trimethylsilane)(R))bis(4- ethynylbenzene-(trimethylsilane))quinone diimine (R = H, Boc) as a model for conjugated and unconjugated porphyrin dye polymers was proposed. The central core of the desired compound, tetrakis(4-ethynlypenyl)quinone-1,4-diimine-2,5-diamine, provided evidence for a charge transfer interaction from the electron richer terminal groups to be more electron poorer benzoquinone ring. The nature of the emission of the core compound was found to be fluorescence at 77K for the case R = H but was too weak to be observed at 298K. No emission was detected for the case R = Boc. Unfortunately, the synthetic route of the desired compound gave the reduced form. The analyses of the reduced compound showed the complete absence of the charge transfer or any communication between the different chromophores due to the broken conjugation between the porphyrin units in the reduced product. This work will be submitted to Journal of Inorganic and Organometallic Polymers and Materials.

The preparation of the shape-persistent carbosilane-functionalized porphyrins H2TPP(4-SiRR’Me)4, Zn(II)- TPP(4-SiRR’Me)4 (R = R’ = Me, CH2CHvCH2, CH2 CH2CH2OH; R = Me, R’ = CH2 CHvCH2, CH2CH2CH2OH; TPP = tetraphenyl porphyrin), H2TPP(4-Si(C6H4-1,4-SiRR’Me)3)4, and Zn(II)-TPP(4-Si- (C6H4-1,4-SiRR’Me)3)4 (R = R’ = Me, CH2CHvCH2; R = Me, R’ = CH2CHvCH2) using the Lindsey condensation methodology is described. For a series of five samples their structures in the solid state were determined by single crystal X-ray structure analysis. The appropriate 0th and 1st generation porphyrin-based 1,4-phenylene carbosilanes form 2D and 3D supramolecular network structures, primarily controlled by either π–π interactions (between pyrrole units and neighboring phenylene rings) or directional molecular hydrogen recognition and zinc–oxygen bond formation in the appropriate hydroxyl-functionalized molecules. UV-Vis spectroscopic studies were carried out in order to analyze the effect of the dendritic branches on the optical properties of the porphyrin ring
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La synthèse de graphène par approche « bottom-up » fait l’objet de nombreux travaux de recherche ayant pour but de contrôler les propriétés électroniques et optiques de ce matériau par la fabrication de nanostructures avec une précision atomique. D’autre part, le contrôle de dopant dans le graphène permettant d’en moduler les propriétés suscite un grand intérêt et dans ce contexte l’utilisation de porphyrines avec un taux d’azote contrôlé est attrayante. Par leurs ressemblances structurelles, les porphyrines π-étendues peuvent être considérées comme des nanoparticules de graphène dopées à l’azote (GQDs) présentant de fortes propriétés infrarouge tandis que les briques de construction à base de porphyrines peuvent être utilisées pour la synthèse sur surface de deux type de nanoarchitectures de graphene appélées nanorubans (GNRs) et nanomèches (GNMs). Cette thèse a pour objectif de développer la synthèse de porphyrines à base d’anthracenes et de les utiliser comme précurseurs pour la fabrication de nanostructures. La première partie de cette thèse est dédiée à la synthèse organique de différentes anthracenylporphyrines et à l’étude de leurs assemblages sur surface dans la chambre d’un microscope à effet tunnel. La seconde partie est dédiée à l’étude de formation de porphyrines π-étendues via une méthode pyrolyse flash pouvant activer thermiquement des réactions de couplage par déhydrogenation entre des hydrocarbures aromatiques polyycliques (PAHs) et des porphyrines. La dernière partie est dédiée à la modification post synthétique d’une tetrabromoanthracenylporphyrine par addition de PAHs via la réaction de couplage de Suzuki-Miyaura et à la caractérisation des propriétés optiques de ces porphyrines nouvellement formées
The synthesis of graphene via bottom-up approach is a hot topic of research that aims to control the electronic and optical properties of this material by the fabrication of atomically precised nanostructures. Moreover, the control of dopant in graphene is of great interest to modulate the properties of the material. In this context, the contribution of porphyrins with a controlled content of nitrogen is attractive in this context. Because of structural similarities with graphene quantum dots (GQDs), π-extented porphyrins can be regarded as nitrogen-doped GQD with promising NIR properties. Porphyrins are convenient building blocks for the synthesis on surface of nanoarchitectures of graphene called nitrogen-doped Graphene Nanoribbons (GNRs) and Graphene NanoMeshes (GNMs). This thesis aims to develop the synthesis of symmetrical and robust porphyrins with anthracenes and to use them as precursors for the fabrication of nanostructures. The first part of this thesis is dedicated to the organic synthesis of variety of anthracenylporphyrins and the study of their assemblies on surface in a chamber of a Scanning Tunneling Microscope. The second part is dedicated to the study of formation of π-extended porphyrins via a method of flash pyrolysis able to thermally activate dehydrogenative coupling reactions between Polycyclic Aromatic Hydrocarbons (PAHs) and porphyrins. The last part is dedicated to the post synthetic modification of a tetrabromoanthracenylporphyrin with additional PAHs via Suzuki-Miyaura coupling and the characterization of the optical properties of the resulting porphyrins

One of the greatest threats to human health is increasing antimicrobial resistance among pathogens, and finding alternatives for treatment of bacterial infections is of highest importance together with a more controlled use of antibiotics. Porphyrins and heme have both been shown to be a promising class of compounds for inactivation of bacteria; porphyrins by their excellent properties to act as a photosensitizer, and heme by its importance as an iron source during a bacterial infection in vertebrates. This thesis describes the development of analytical methods for the identification and determination of porphyrins and heme using liquid chromatography coupled to tandem mass spectrometry. Subsequently, these developed methods were applied to bacterial samples to investigate different culture conditions and additives effect to the intracellular porphyrin and heme composition. Singlet oxygen production of three naturally occurring porphyrins have been determined together with the photosensitivity for blue light and the porphyrin content in E. coli. Toothbrushes equipped with a LED, emitting light with a wavelength of 450 nm, were used in an eight week randomized clinical trial to investigate any positive periodontal effect of blue light. Porphyrin and heme content in Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis were highly affected by the different cultivation conditions. The culture age of A. actinomycetemcomitans affected the porphyrin profile, while only small changes were observed for P. gingivalis during growth. A large change of the porphyrin profile could be observed when the bacteria were passaged onto a new growth medium. Additional porphyrins were detected and the total porphyrin content increased up to 28 times. These findings highlight the need for more standardized cultivation procedures when performing in vitro experiments. Heme content in Escherichia coli was affected when different additives related to biosynthesis of heme were added to the growth medium. The uptake of heme could be reduced with 52% when a compound that chemically looks similar to heme was added to the growth medium. Since heme acquisition is important for many pathogens, this could be a promising target for antimicrobial drugs. E. coli showed no sensitivity for 405 nm light using light doses up to 172.8 J/cm2 and only low concentrations of porphyrins could be quantified. By adding a porphyrin precursor to E. coli the intracellular concentration of porphyrins increased remarkably and a light dose of 57.6 J/cm2 reduced the bacterial number with > 5 log10 steps. This shows that E. coli can be killed due to their endogenous porphyrins. In the clinical study we could see a weak trend that the 450 nm LED toothbrush possessed a phototherapeutic effect for three clinical indices. All indices were decreased in the intervention group, but there were no statistically significant difference compared to the control group. However, four inflammation markers were significantly decreased in the intervention group while only one decreased significantly in the control group. In conclusion, this thesis has shown that porphyrins and heme are produced endogenously in microorganisms and that the porphyrin profiles vary depending on culture conditions and different additives. Furthermore, porphyrins may be used as endogenous photosensitizers to inactivate bacteria, but more research is necessary to determine if there is a specific porphyrin that contributes more to the photosensitivity.

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 4: Manuscript. Paper 5: Manuscript.

Abstract : The transfer of energy between excited state chromophores is a topic of interest in the area of natural and laboratory photonic devices. Indeed, energy transfer is a process seen in nature in all photosynthetic organisms from complex multicellular plants to simple, single cell photosynthetic bacteria. For example, the purple photosynthetic bacteria uses two protein assemblies, referred to as the light-harvesting protein 1 (LH1) and the light-harvesting protein 2 (LH2), to collect light energy in order to survive. The LH2 protein serves only to absorb and transmit light energy to the LH1, which contains a special pair in a central reaction center. Energy transfer is essential to the survival of the organism. A photon of light absorbed by a bacteriochlorophyll molecule in the LH2 protein will undergo efficient energy transfer to other bacteriochlorophylls within the same protein structure. Energy transfer will also occur between different LH2 proteins and between the LH2 and LH1 protein. These energy transfer processes all serve to funnel the light to the reaction center which itself is excited by energy transfer. This process is highly efficient and essential to the organism’s survival. In the area of material sciences, the design of a covalent or non-covalent donor-acceptor assembly that exhibits efficient energy transfer, is a topic of interest for application in solar energy and light emitting diodes. Using the purple photosynthetic bacteria as a model, designs that append different dyes that serve to absorb and transmit light energy to a central backbone (a process referred to as the antenna effect) are being investigated. The principle being that the use of these antenna allows for the absorption of more light in regions of the electromagnetic spectrum that we cannot necessarily obtain with a single dye. The fall-back is that, in order for the process to work efficiently, the energy transfer between the antenna and backbone must be rapid. This work presents an investigation of the energy transfer processes between oligopyrrole dyes that are bridged by a truxene core, which exhibits a structural similarity to graphene. The aim of this work is to further understand the energy transfer processes between chromophores. We demonstrate in our work that the presence of a conjugated bridge between the donor and acceptor provides the possibility of a dual energy transfer process governed by both the Förster and Dexter mechanisms. We demonstrate that the use of this conjugated bridge leads to a very fast energy transfer process despite the large distance that separates the donor and acceptor. We further demonstrate that the process, although being a dual process, is dominated by the Dexter ix mechanism which is mediated by the conjugated system connecting the donor and acceptor. The rapid and efficient energy transfer processes suggest that in order to take full advantage of the antenna effect in man-made photonic devices, designs should be built upon the use of conjugated bridges between the donor and acceptor. The work presented in this thesis is divided into eight sections. In the introduction, a brief description of the chromophores that are seen throughout the rest of this work, is provided along with some general concepts with regard to density functional theory (DFT), which was employed as a tool throughout the presented works to demonstrate a certain degree of molecular orbital coupling. Chapter 1, entitled The Basic Principles of Photophysics, provides an introductory explanation of the theory that is required to fully understand the works that are presented in this thesis. Chapter 2 is simply entitled Instrumentation and serves to provide a description of the instruments used throughout the works. In Chapter 3: Maple™-Assisted Calculations of the J-integral: A Key Parameter for the Understanding of Excited State Energy Transfer in Porphyrins and other Chromophores a detailed description of the J-integral is provided and a tool for is calculation from spectral data is presented. The investigation of the energy transfer processes between truxene bridged chromophores begins in Chapter 4: Origin of the Temperature Dependence of the Rate of Singlet Energy Transfer in a Three-Component Truxene-bridged Dyads. In this chapter, the energy transfer between a Zn-porphyrin donor and a set of free-base porphyrin acceptors is investigated. Circumstantial evidence suggests that the energy transfer process that is observed, is occurring through a dual mechanism that may be dominated by the Dexter mechanism is provided. Chapter 5: Antenna Effect in Truxene-bridged BODIPY Triarylzinc(II)porphyrin Dyads: Evidence for a Dual Dexter-Förster Mechanism presents the investigation of the energy transfer processes between a BODIPY donor and two zinc(II)-porphyrin acceptors. In this chapter the comparison of the the energy transfer process to a similar dyad, that contains a non-conjugated bridge between the donor and acceptor, is made and it is shown that the truxene bridged dyad not only presents a faster rate, but that this faster rate can only be explained by a Dexter dominant process. In Chapter 6: Very Fast Singlet and Triplet Energy Transfers in a Tri-chromophoric Porphyrin Dyad Aided by the Truxene Platform the investigation of the energy transfer between a palladium(II)-porphyrin donor and pair of Zn-porphyrin acceptors bridged by a truxene core is x carried out. Here, a very fast triplet energy transfer process is observed, coroborating that the conjugated system promotes the Dexter process and leads to an efficient transfer of energy from the donor to the acceptor. Finally, Chapter 7 presents the last work that is included in this thesis. Chapter 7 is entitled Excited State N-H Tautomer Selectivity in the Singlet Energy Transfer in a Zinc(II)Porphyrin-Truxene-Corrole Assembly and once again presents a very fast and efficient energy transfer process. In this work the energy transfer occurs between a Zn-porphyrin donor and a set to free-base corrole acceptors. The rapid energy transfer process exhibits a rate constant that falls in the same order of magnitude of those presented in the earlier chapters, suggesting that the process is occurring through the same dual mechanism that is Dexter dominated. Interestingly, in this last the energy transfer process was found to occur selectively to only one of the two corrole tautomeric species. This prompted an investigation into the excited state tautomerization rates of the free base corrole and lead to the first report of an experimentally measured tautomerization rate from free-base corrole. This thesis closes with a general discussion of the works presented within its pages and a discussion of the impact that the results have on the scientific community.
Les transferts d’énergie entre les états excités de chromophores est un sujet d’intérêt dans le domaine des dispositifs photovoltaïques naturelles ou artificielles. En effet, le transfert d’énergie est un processus que l’on observe dans la nature au sein de tous les organismes phototrophes depuis les végétaux multicellulaires complexes jusqu’aux bactéries unicellulaires photosynthétiques. Par exemple, dans le cas des bactéries photosynthétiques pourpres, ces dernières utilisent un photosystème de deux protéines assemblées, la première étant appelé protéine collectrice de lumière 1 (LH1 pour light-harvesting protein 1) et la seconde appelé protéine collectrice de lumière 2 (LH2 pour light-harvesting protein 2) afin de capter suffisamment d’énergie lumineuse pour assurer leur survie. La protéine LH2 n’a pour vocation que d’absorber et de transmettre l’énergie lumineuse à la protéine LH1, qui contient une paire spéciale dans un centre réactionnel. Les transferts d’énergie sont des phénomènes essentiels à la survie des organismes. Un photon absorbé par une molécule de type bactériochlorophylle dans la protéine LH2 subira un transfert d’énergie efficace à d’autres bactériochlorophylles au sein de la même structure protéique. Les transferts d’énergie se dérouleront aussi bien entre différentes protéines LH2 qu’entre des protéines LH1 et LH2. Ces processus de transfert d’énergie servent à canaliser l’énergie lumineuse jusqu’au centre réactionnel qui devient à son tour excité par transfert d’énergie. Ces processus sont hautement efficaces et essentiels à la survie de l’organisme en question. En science des matériaux, la conception d'un assemblage donneur-accepteur, covalent ou non, qui présente un transfert d'énergie efficace est un sujet d'intérêt pour des applications en photovoltaïque et diodes émettrices de lumière. En utilisant les bactéries pourpres photosynthétiques comme modèle, des structures similaires étudiant différents colorants permettant d'absorber et de transmettre de l'énergie lumineuse à un squelette central (un processus appelé effet antenne) font l'objet de recherches actives. Le principe étant que l'utilisation de ces antennes permet d'absorber plus de lumière dans les régions du spectre électromagnétique qu’il serait impossible d’obtenir avec un seul colorant. La conséquence est que, pour que le processus fonctionne efficacement, le transfert d'énergie entre l'antenne et le squelette doit être rapide, et parfois contrôlé. Dans ce travail, nous étudierons les processus de transfert d'énergie entre des colorants oligopyrroliques reliés par un noyau truxène, qui montre une similarité structurale avec le graphène. L'objectif du travail est de mieux comprendre les processus de transfert d'énergie entre les chromophores. Nous montrerons dans notre travail que la présence d'un système conjugué entre le donneur et l'accepteur ouvre la porte à l’hypothèse de la présence d'un double processus de transfert d'énergie régi par les mécanismes Förster et Dexter. Nous démontrerons que l'utilisation de ce système conjugué conduit à un processus de transfert d'énergie très rapide malgré la distance importante séparant le donneur et l’accepteur. Nous démontrerons en outre que le processus, bien qu'il s'agisse d'un double processus, est dominé par le processus Dexter grâce au système conjugué reliant le donneur et l'accepteur qui fait office de pont communiquant. Les processus de transfert d'énergie rapides et efficaces suggèrent que, pour tirer pleinement parti de l'effet antenne dans des applications photovoltaïques, les designs devraient être basés sur l'utilisation de ponts conjugués reliant donneurs et accepteurs. Le travail présenté dans cette thèse est divisé en huit sections. Dans l'introduction, une brève description des chromophores utilisés tout au long du présent travail sera fournie avec des concepts généraux non-exhaustifs pour la théorie de la fonctionnelle de la densité (DFT) qui a été utilisé comme outil tout au long des travaux actuels pour démontrer un certain degré de couplage orbitalaire. Le chapitre 1, intitulé Les principes fondamentaux de la photophysique, proposera une introduction à la théorie nécessaire à la bonne compréhension des travaux présentés dans cette thèse. Le chapitre 2 est simplement intitulé Instrumentation et fournira une description des instruments utilisés tout au long des travaux. Au chapitre 3: « Maple™-Assisted Calculations of the J-integral: A Key Parameter for the Understanding of Excited State Energy Transfer in Porphyrins and other Chromophores », une description détaillée de l'intégrale J ainsi qu’un outil pour le calcul à partir de données spectrales seront exposés. L'étude des processus de transfert d'énergie entre les chromophores pontés par truxène commencera au chapitre 4: « Origin of the Temperature Dependence of the Rate of Singlet Energy Transfer in a Three-Component Truxene-bridged Dyads ». Dans ce chapitre, nous étudierons le transfert d'énergie entre un donneur de type zinc(II)-porphyrine et un ensemble d'accepteurs de porphyrine base libre. Des preuves circonstancielles indiquant que le processus de transfert d'énergie observé se produit à travers un double mécanisme qui peut être dominé par le mécanisme Dexter seront présentées. Le Chapitre 5: « Antenna Effect in Truxene-bridged BODIPY Triarylzinc(II)porphyrin Dyads: Evidence for a Dual Dexter-Förster Mechanism » présentera quant à lui l'étude des processus de transfert d'énergie entre un donneur BODIPY et deux accepteurs de type Zn-porphyrine. Dans ce chapitre, la comparaison du processus de transfert d'énergie à une dyade similaire qui contient un pont non-conjugué entre le donneur et l'accepteur sera effectuée et il sera démontré que la dyade ponté par truxène présente non seulement un taux plus rapide, mais que ce taux ne peut être expliqué que par un processus Dexter dominant. Au chapitre 6 : « Very Fast Singlet and Triplet Energy Transfers in a Tri-chromophoric Porphyrin Dyad Aided by the Truxene Platform », l'étude du transfert d'énergie entre une porphyrine de palladium(II) donneuse et une paire d'accepteurs de type zinc(II)-porphyrine pontés par un noyau de truxène sera montré. Ici, un processus de transfert d'énergie triplet très rapide est observé, ce qui prouve que le système conjugué favorise le processus Dexter et conduit à un transfert efficace d'énergie du donneur vers l'accepteur. Enfin, le chapitre 7 présentera le dernier travail inclus dans cette thèse. Le chapitre 7 est intitulé « Excited State N-H Tautomer Selectivity in the Singlet Energy Transfer in a Zinc(II)Porphyrin-Truxene-Corrole Assembly » et exposera une dernière fois un processus de transfert d'énergie très rapide et efficace. Dans ce travail, le transfert d'énergie se produit entre un donneur de type Zn-porphyrine et une corrole base libre acceptrice. Le processus de transfert d'énergie rapide présente une constante de vitesse qui se situe dans le même ordre de grandeur que ceux présentés dans les chapitres précédents, ce qui suggère que le processus se produit par le biais du même double mécanisme dominé par Dexter. Il est intéressant de noter que, dans ce dernier cas, le processus de transfert d'énergie s'est révélé sélectif sur l'une des deux espèces tautomériques du corrole. Ceci a mené à une étude sur les taux de tautomérisation de l'état excité de la corrole base libre conduisant à la premier mesure expérimentale du taux de tautomérisation de la corrole base libre. Cette thèse s’achèvera par une discussion générale sur les travaux présentés dans ces pages ainsi que sur l'impact que les résultats ont eus dans communauté scientifique dans ce domaine.

Diese Dissertation leistet einen Beitrag zum Verständnis des Energie- und Elektronentransfers innerhalb von neuartigen supramolekularen Strukturen, die aus einem zentralen Phthalocyanin und zwei axial angekoppelten Porphyrinen bestehen. Zwei solcher Trimere, welche die koordinative Ankopplung von Porphyrinen über ein Silizium-Zentralatom des Phthalocyanins nutzen, wurden im Rahmen der Arbeit zum ersten Mal quantitativ bezüglich auftretender innermolekularer Transferprozesse charakterisiert. Ziel war die Beantwortung der Frage, ob diese Substanzklasse die wunschgemässe Vereinigung von Lichtsammlung und Ladungstrennung ermöglicht. Aus der Kombination der Messdaten, aufgenommen mit einer Vielzahl von Messverfahren, konnten für die beiden untersuchten Trimere in zwei unterschiedlich polaren Lösungsmitteln die Ratenkonstanten der Energie- und Ladungstransferkanäle ermittelt werden. In allen Fällen findet ein effizienter Ladungstransfer von den Porphyrinen zum Phthalocyanin und ein Lochtransfer vom Phthalocyanin zu einem der beiden Porphyrine statt. Dieses Ergebnis bestätigt die Erwartung, dass Lichtsammlung und Ladungstrennung in diesem Molekül vereint auftreten. Zusätzlich zu den beiden oben erwähnten Prozessen findet je nach Lösungmittelpolarität und Struktur der Porphyrine ein dem Energietransfer paralleler Elektronentransfer und ein Ladungsrücktransfer statt. Allerdings zerfällt der ladungsseparierte Zustand zu schnell, was eine praktische Nutzung der untersuchten Verbindungen in Solarzellen noch verhindert und ihre Weiterentwicklung erfordert.
This thesis contributes to the comprehension of energy and electron transfer within novel supra-molecular structures, denominated triads, consisting of a central phthalocyanine axially-coupled to two porphyrins. In the course of this thesis, two of the trimers, were quantitatively characterized regarding their intramolecular transfer processes. Both feature a dative bond between the porphyrins and the phthalocyanine via the central silicium atom of the latter. These investigations aimed at answering whether this class of compounds allows the desired combination of light harvesting and charge separation. The rate constants of both investigated trimers in two solvents with different polarity were determined by the combination of data from a variety of measurement methods. An efficient charge transfer from the porphyrins to the phthalocyanine and a hole transfer from the phthalocyanine to one of the porphyrins occurs in all investigated cases. This result confirms the prospect that light harvesting and charge separation can occur combined in one molecule. Depending on solvent polarity and the structure of the porphyrines, electron transfer parallel to the energy transfer and a charge back transfer takes place in addition to both above-mentioned processes. However, the charge-separated state of the investigated substances decays to fast, still preventing a practical utilization of these compounds in solar cells and necessitating further developments.

Visant des applications en électronique moléculaire, de nouveaux édifices moléculaires combinant quatre dithiényléthènes (DTEs) et une porphyrine ont été synthétisés par de nouvelles voies de synthèse. Les études en solution par photochimie ou spectroélectrochimie des édifices tetraDTEs-porphyrine métallée ou base livre ont montré l’efficacité (62-88 pourcent) des photochromes en tant qu’interrupteurs et la possibilité de lire l’état des DTEs par la fluorescence de la porphyrine. Pour mieux comprendre les interactions électroniques DTEs- porphyrines, des édifices plus simples, bis(porphyrine)DTE, déjà partiellement étudiés dans la littérature, ont été explorés. L’ensemble de ces études à mis en évidence l’impact des métaux sur la capacité photochromique des édifices dithiényléthène – porphyrine
The main purpose of this thesis was the synthesis of new molecular structures, combining dithienylethenes and porphyrins, for applications in molecular electronics and spintronic. Metallated and free base porphyrins bearing four DTEs were characterizes and studied in solution by photochemistry and spectroelectrochemistry. The efficiency of switching of our systems reach 88 percent and strong quenching porphyrin’s fluorescence was reported. New synthetic pathways were investigated to prepare a broader scope of tetraDTEs-porphyrin derivatives. Moreover, to better understand the electronic communications between DTEs and porphyrins, a simpler bis(porphyrin)DTE molecular structure was synthetized and studied. These studies demonstrated showed the important role of the metal on photochromic behavior of dithienylethene – porphyrin architectures

L’objectif des travaux de cette thèse était de développer un système de délivrance stimulus-sensible innovant. Basé sur des vésicules lipidiques, il permet la libération d’une substance anti-cancéreuse hydrophile encapsulée dans leur cœur aqueux, sous l’effet de la lumière. Des porphyrines, incorporées dans leur bicouche, permettent, une fois illuminées, de générer de l’oxygène singulet qui oxyde les chaînes acyl insaturées des phospholipides. Cela induit une augmentation de la perméabilité des liposomes et permet la libération de leur cargo. Nous avons, dans un premier temps, effectué une sélection de phospholipides et de porphyrines permettant de construire le système. Les résultats expérimentaux ont pu être corrélés à une étude de simulation de dynamique moléculaire. L’ensemble a mis en exergue l’importance de la profondeur d’insertion de la porphyrine dans la bicouche lipidique et de sa proximité avec la double-liaison des phospholipides. Mais il a aussi montré les limites de ce système. Nous avons alors développé deux nouvelles molécules, dérivées de phospholipides naturels auxquels a été couplée la pheophorbide a. Malgré leur possible autoassemblage sous la forme de vésicules, ces derniers n’étaient pas stables et s’agrégeaient rapidement. Nous avons donc associé ces conjugués à des lipides classiques (DSPC, cholestérol) et analysé les propriétés des mélanges obtenus. Les propriétés photothermiques des systèmes conçus ont été confirmées, capables d’induire une élévation en température de 14°C. La chaleur générée, responsable d’une plus grande fluidité de la bicouche lipidique, a permis de favoriser la libération du cargo. Enfin, les deux conjugués synthétisés ont montré eux-mêmes une activité phototoxique (PDT), additionnée d’une sélectivité vis-à-vis de cellules du cancer de l’œsophage. Ces nouvelles molécules offrent donc de nombreuses opportunités pour le développement de systèmes multimodaux, bio-inspirés et biodégradables, pour la délivrance d’un médicament sous l’effet de la lumière
The aim of this work was to develop an innovative stimulus-responsive delivery system. Based on lipid vesicles, it allows the controlled release, by light, of a hydrophilic anti-cancer substance encapsulated in their aqueous core. Once illuminated, porphyrin molecules inserted into the lipidic bilayer, generate singlet oxygen which oxidizes the unsaturated acyl chains of the phospholipids. This induces an increase in the permeability of the liposomes and the release of their cargo. We first made a selection of phospholipids and porphyrins to build the system. Our experimental study could be correlated with results of molecular dynamics simulations. The whole work highlighted the importance of the depth of insertion of porphyrin into the lipid bilayer and its proximity to the double bond of phospholipids. But it also showed the limits of this system. We then developed two new molecules, derived from natural phospholipids, to which pheophorbide a was coupled. The conjugates were able to form self-assembled vesicles but were unstable and quickly aggregated. We therefore associated these conjugates with classical lipids (DSPC, cholesterol) and analyzed the properties of these mixtures. We highlighted photothermal properties of the designed systems, capable of inducing a temperature rise of 14 °C. The generation of heat, responsible for a greater fluidity of the lipid bilayer, subsequently promoted the encapsulated cargo release. Finally, the two synthesized conjugates showed a phototoxic activity (PDT), with selectivity towards esophageal cancer cells. These new molecules therefore offer many opportunities for the development of multimodal, bio-inspired and biodegradable systems, for the delivery of a drug under the effect of light

Les travaux décrits dans ce manuscrit s’intéressent au contrôle du mouvement moléculaire. Après une introduction dédiée à l’état de l’art des machines moléculaires, le premier chapitre s’intéresse à la conception de tourniquets moléculaires à base de complexes porphyriniques de P(V). Le mouvement moléculaire a pu être contrôlé de manière réversible soit par l’utilisation des sites de coordination présents à la périphérie du système soit par des variations de pH. Le deuxième chapitre s’intéresse aux propriétés photophysiques des porphyrines de P(V) obtenues et plus particulièrement à leur capacité à générer de l’oxygène singulet avec une application potentielle en Thérapie Photodynamique (PDT).Le troisième chapitre concerne l’élaboration d’un complexe contenant deux porphyrines de Zn(II) dont le mouvement relatif a pu être bloqué réversiblement par l’utilisation des positions axiales des cations métalliques
The manuscript focuses on molecular machines and the control of their movement. Two different devices have been designed, synthetized and characterized. Moreover, a series of new potential photosensitizer was obtained.The introduction gives a general overview on molecular machines, reported during the past 20 years. The first chapter describes the synthesis of molecular turnstiles based on P(V) porphyrins. The molecular motion was controlled reversibly using either coordination chemistry or by changing the pH. The second part is dedicated to the study of the photophysical properties of P(V) porphyrins and especially their capacity to generate singlet oxygen under irradiation., making them potential photosensitizers that can be use in Photodynamic Therapy (PDT) or as catalyst. The third chapter is devoted to the study of a molecular break based on a Zn (II) porphyrin dimer. The control of the movement was performed using the coordination of a bidentate ligand in the axial position of the metal cations

Des films du type polyoxométallates-porphyrines ont été synthetisés et sont basés sur des interactions du types covalentes ou électrostatiques. Les films polyoxométallates–porphyrines sont obtenus par électro-oxydation de l’octaéthylporphyrine de zinc (ZnOEP) ou la 5,15-ditolylporphyrine (H2T2P) en présence de différents types of polyoxométallates (POMs) portant deux groupes pyridyles pendants (py-POM-py) Trois type de systèmes py-POM-py ont été utilises : i) un Lindqvist polyoxovanadate fonctionalisé via deux groupes tris-alkoxo , ii) un derive organosilyl fonctionalisé du type Keggin ou Dawson, et iii) des briques du type Dawson [P2W15V3O62]9− fonctionalisée avec des groupements organiques bis-pyridine de géométrie variée via un greffage diolamide). Tous ces films ont été testé pour la génération de photocourant et la photocatalyse de la réduction de métaux (Ag et Pt). Des films électrostatiques POM-porphyrin ont été également préparés par incorporation de polyanion du type Preyssler [NaP5W30O110]14- sur les films de porphyrine polycationic (poly-ZnOEP) électropolymérisés avec des espaceurs viologènes ou bis-viologènes. [NaP5W30O110]14- agit comme relais d’électron entre une porphyrine excitée ZnOEP* et le viologène (ou le bis-viologène) retardant la recombinaison de charge ce qui permet une augmentation du photocourant. Enfin, des nanoparticules POM@NPs (Pt, Au, Ag) ont été introduites en surface de copolymère polycationique à base de bis-porphyrine par métathèse afin d’augmenter l’efficacité de la génération de photocourant. La résonance de plasmon de surface localisée qui se produit à la surface des nanoparticules d'argent a sensiblement améliorée l'excitation électronique de porphyrine
Polyoxometalates-porphyrin hybrid films were synthesized based on covalent or electrostatic interactions. Copolymeric polyoxometalate–porphyrin films were obtained by the electro-oxidation of zinc octaethylporphyrin (ZnOEP) or 5,15-ditolyl porphyrin (H2T2P) in the presence of a different type of polyoxometalates (POMs) bearing two pyridyl groups (py-POM-py). Three type of py-POM-py have been used: i) a tris-alkoxo functionalized Lindqvist polyoxovanadate, ii) an organosilyl functionalized Keggin-type [PW11Si2O40C26H16N2]3- and Dawson-type [P2W17Si2O62C26H16N2]6-, and iii) a bis-pyridine-substituted organo-polyoxometallic bricks using [P2W15V3O62]9− diolamide-grafting method with various geometries of the pendant group. All are applied for photocurrent generation and photocatalytical recovery of metals (Ag and Pt). Electrostatic POM-porphyrin films were also prepared by incorporated Preyssler type polyanion [NaP5W30O110]14- onto the electropolymerized polycationic porphyrin (poly-ZnOEP) with viologen or bis-viologen as spacers. [NaP5W30O110]14- as an efficient electron shuttle between the excited ZnOEP and viologen (or bis-viologen) which effectively retarded the fast charge pair recombination and enhanced the photocurrent magnitude. Later, we introduced nanoparticles POM@MNPs to a bis-porphyrin copolymer through metathesis reaction to further improve the efficiency of the photocurrent generation in which the localized surface plasmon resonance that occurs at the surface of silver nanoparticles has substantially enhanced the electronic excitation of surface-anchored porphyrin

Ziel dieser Arbeit war die Kontrolle über bestimmte Eigenschaften von Molekülen. Dabei lag ein besonderes Interesse auf der Steuerung der Zugänglichkeit eines katalytisch aktiven Zentrums durch die großen geometrischen Veränderungen bei der E->Z Isomerie von photochromen Verbindungen. Ein weiterer Vorteil dieser photochromen Verbindungen liegt in der Reversibilität der E-Z Isomerisierung, so dass das katalytische Zentrum mehrmals „an“ und „aus“ geschaltet werden kann. In der Literatur sind nur sehr wenige Beispiele solcher photoschaltbaren Katalysatoren bekannt. Diese besitzen teilweise schwerwiegende Nachteile, wie z.B. geringe Reaktivitätsunterschiede oder eine begrenzte Anwendbarkeit, aufweisen. Die Aufgabe in dieser Arbeit bestand in der Entwicklung eines neuen photoschaltbaren Katalysatorsystems, welches sich durch größere Reaktivitätsunterschiede und eine breitere Anwendbarkeit auszeichnet. Das erste Design bestand aus einem photoschaltbaren Metalloporphyrin als Katalysator für Polymerisations- oder Oxidationsreaktionen. Nach erfolgreicher Synthese wurden die Schalteigenschaften untersucht. In einem zweiten Design wurde ein photoschaltbarer Organokatalysator hergestellt und dessen Schaltverhalten, sowie dessen Eignung als Katalysator in einer generellen Basenkatalyse, erfolgreich getestet.
The aim of this work was to control the properties of molecules. Our special interest lies in controlling the accessibility of a catalytic active center by using the big geometric changes of photochromic groups, such as E->Z isomerization of azobenzene or stilben. Another advantage of these photochromes is the reversibility of the Z -> E isomerization, so that the catalytic active center can be switched several times. Only few examples of photoswitchable catalysts are known in literature, having several disadvantages like small activity ratios or narrow scope. The goal of this work was to design a new photoswitchable catalyst having bigger activity ratios and broader applicability. The first design consisted of a photoswitchable metalloporphyrin as catalyst for polymerization or oxidation reactions. After successful synthesis the switching properties were investigated, showing no isomerization possibility. In a second approach a photoswitchable organo catalyst was established. The switching properties were investigated and the catalyst was successfully tested in general base catalysis.

Le cancer colorectal (CCR) est le troisième cancer le plus commun diagnostiqué dans le monde entier. Les limites de la chimiothérapie à base de cisplatine ont incité les scientifiques à rechercher de nouveaux médicaments anti-cancéreux à base de métal. Les complexes à base d’or(III) ont été parmi les plus largement étudiés puisqu’ils ont montré une plus importante cytotoxicité in vitro que le cisplatine ainsi que des activités anti-cancéreuse in vivo dans le CCR, mais leur utilisation clinique a été limitée en raison de leur faible stabilité dans des conditions physiologiques. De nouveaux complexes à base d’or(III) couplés à la porphyrine [or(III)/chlorure d’adamantane-porphyrine (SN1) et or(III)/chlorure de mono-acétateporphyrin (SN2)] avec une stabilité en solution aqueuse améliorée ont été synthétisés. SN1 et SN2 réduisent la survie des lignées humaines HT-29 et HCT-116 de CCR, causent l'arrêt du cycle cellulaire en phase G2/M, et nous avons observé une diminution de l'expression de la cycline B1 et de la kinase « cyclindépendant 1 » (Cdk1) avec une surexpression de la forme active de p53, p21 et de « Bcl-2-associated X » (Bax). En outre, SN1 et SN2 induisent l’apoptose par la voie intrinsèque, puisqu'ils mènent au clivage de la caspase 9, la caspase 3 et la poly(ADP-ribose) polymérase (PARP) tout en augmentant l’expression de Bax. La phosphatidylinositol-3-kinase/protéine kinase B (PI3K/Akt), le facteur nucléaire κB (NF-κB) et l’ « extracellular signal-regulated kinase » (ERK) sont importants pour la survie cellulaire et la prolifération. SN1 et SN2 entrainent une diminution de l'activité d'Akt où la forme phosphorylée diminue avec le temps, mais aussi ils causent une diminution importante dans la phosphorylation d'ERK et l'activité de NF-κB. Finalement, les complexes SN1 et SN2 ciblent la voie p38/« mitogen-activated protein kinase » (MAPK) entrainant une augmentation de l'expression de la cyclooxygenase-2 et de son produit enzymatique la prostaglandine E2
Colorectal cancer (CRC) is the third most common cancer diagnosed worldwide. The limitations of cisplatin-based chemotherapy have prompted intense interest among scientists to search for alternative metal-based anticancer medicines. Gold(III) complexes have been among the most widely investigated since they showed higher cytotoxicity than cisplatin and promising in vitro and in vivo anticancer activities in CRC but their clinical usefulness has been limited by their poor stability under physiological conditions. A novel gold(III) porphyrin complexes [gold(III) porphyrin-adamantane chloride (SN1) and gold(III) porphyrin mono-acetate chloride (SN2)] with improved aqueous stability were synthesized. SN1 and SN2 reduced the survival of human CRC HT-29 and HCT-116 cell lines, caused cell cycle arrest in G2/M phase, and we observed downregulation of the expression of cyclin B1 and cyclin-dependent kinase 1 (Cdk1) along with up-regulation of the active form of p53, p21 and Bcl-2–associated X (Bax). Furthermore, SN1 and SN2 induced apoptosis by the intrinsic pathway, since they lead to the cleavage of caspase 9, caspase 3 and poly(ADP-ribose) polymerase (PARP), and up-regulating Bax. Phosphatidylinositol-3-kinase/protein kinase B (PI3K/Akt), nuclear factor-κB (NF-κB) and extracellular signal-regulated kinases (ERK) are important for cell survival and proliferation. SN1 and SN2 lead to decrease in the activity of Akt where thephosphorylated form decreased with time as well as they caused an important decrease in the phosphorylation of ERK and activity of NF-κB. Finally, SN1 and SN2 complexes affected p38/mitogenactivated protein kinase (MAPK) pathway then we recorded an increase in the cyclooxygenase-2 expression and its enzymatic product prostaglandin E2

Chemische Synthese und Charakterisierung von Sauerstoff- und Schwefel-Heteroporphyrinen und ihren Mn(II)-, Co(II)-, Cu(II)-, Zn(II)- und Pd(II)-Komplexen. Strukturelle und spektroskopische Beschreibung der Liganden und Komplexe durch Röntgendiffraktometrie, EXAFS, NMR, UVVIS, Fluoreszenzspektroskopie, CV unf MS. Darstellung und Beschreibung dendritischer Heteroporphyrinmoleküle.

Background:   Porphyrias are inherited disorders with impaired heme biosynthesis. Acute intermittent porphyria (AIP) is the most common porphyria in Sweden. AIP attacks may be life-threatening. Female sex hormones are regarded as important precipitating factors. Hepatocellular carcinoma (HCC) is a severe complication in the older AIP population. The aim of the thesis was to describe the clinical expression of AIP in women, experience of hormonal contraception and hormonal replacement therapies (HRT) and of pregnancies. Secondly, we evaluated gonadotropin-releasing hormone (GnRH) agonist treatment for prevention of menstrual-cycle-related AIP attacks. Thirdly, we evaluated whether an altered sex-steroid metabolism was present in AIP women compared with controls. Finally, we evaluated the benefit of screening for HCC in AIP in a 15-year follow-up study. Methods and results: In a retrospective population-based study in northern Sweden, 166 female AIP gene carriers ≥18 years of age participated. Manifest AIP (MAIP) was reported in 55%; 82% had severe attacks and 39% had menstrual-cycle-related attacks. Hormonal contraceptives were used by 94, and 12 reported that this precipitated AIP attacks. HRT and local vaginal treatments in menopause did not precipitate AIP attacks. Only 10% reported impairment of AIP symptoms during pregnancy. In the retrospective follow-up study of GnRH-agonist treatment, 11 of 14 women improved during treatment. Porphyria attacks were triggered in two women after estradiol add-back and in 5 of 9 women after progesterone add-back. In the sex-steroid metabolism study, levels of s-progesterone, estradiol, allopregnanolone and pregnanolone during the menstrual cycle in 32 AIP gene carriers were compared with 20 healthy controls. Progesterone metabolism in the AIP group differed from controls. In the AIP group levels of allopregnanolone, but not pregnanolone, were significantly lower. In the prospective HCC screening study AIP gene carriers aged >55 years were included. On average 62 subjects participated during 15 years. HCC was diagnosed in 22 of 180 eligible AIP gene carriers in the region (male:female, 12:10, 73% MAIP). The annual incidence of HCC was 0.8%. The risk of HCC was 64-fold higher than in the general population over 50 years of age in this region, and even higher for AIP women (93-fold). Increased 3- and 5-year survival was seen in the regularly screened AIP group. Liver lab tests were not useful in HCC screening. Conclusion: The clinical expression of AIP in women is pronounced and menstrual-cycle-related attacks are common. Hormonal contraceptives can induce AIP attacks and caution is recommended. GnRH-agonist treatment can ameliorate menstrual-cycle-related attacks of porphyria. Dose findings for GnRH-agonists and add-back regimes, especially for progesterone, are intricate. Progesterone metabolism in the AIP group differs from that in healthy controls. HCC screening in AIP gene carriers >50 years of age enables early diagnosis and a possibility for curative treatments. Annual HCC screening with liver imaging is recommended in AIP gene carriers >50 years of age.

The research presented in this dissertation deals with the syntheses, characterization, electrochemical and photophysical studies of porphyrin-fullerene or porphyrin-carbon nanotube based donor-acceptor conjugates. The first chapter provides an introduction to the research presented in this thesis. A summary of primary events that occur in natural photosynthetic systems, the necessity and importance of the artificial photosynthetic mimics for light energy harvesting, the importance of non-covalent porphyrin-fullerene donor-acceptor models over covalent ones and some recent developments in model biomimetic systems are presented. Additionally, the importance of the nano-sized materials, solubilization of carbon nanotubes via chemical functionalization and utilization of these nanomaterials in building donor-acceptor nanohybrids is discussed. The second chapter discusses the syntheses and characterization of the control compounds and physical methods employed to monitor the photochemical pathways occurring in the studied donor-acceptor conjugates. The third chapter focuses on the design and syntheses of rigid, noncovalent “two-point” bound porphyrin-fullerene dyads assembled via crown etherammonium cation complexation and axial coordination or ∏-∏ interactions. The effect of axial ligation or ∏-∏ interactions in addition to the crown etherammonium cation binding, on photochemical charge stabilization in these supramolecuar dyads is systematically investigated. The fourth chapter deals with the photoinduced electron-transfer processes occurring in supramolecular triads comprised of cis and trans functionalized bis-18-crown-6 porphyrin self assembled with fullerene functionalized with pyridine or alkyl ammonium cation entities. The 1:2 stoichiometric supramolecular porphyrin:fullerene conjugates are obtained by utilizing either “two-point” binding methodology involving metalligand coordination and alkyl ammonium cation-crown ether binding or the latter type of binding solely. Variation of metal ion in the porphyrin (zinc or magnesium) cavity results in the free energy changes of charge separation and charge recombination. Employing higher number of the acceptor entities improves the electron-transfer rates, with kCS being 2-3 orders of magnitude higher than the kCR, thus indicating charge stabilization in these conjugates. The fifth chapter discusses the role of a secondary electron donor in generating longlived charge separated states in supramolecular conjugates formed via crown ether-ammonium cation binding. The sixth chapter presents the application of the present type of conjugates. Here, potassium ion-induced switching of intrato intermolecular electron transfer in crown ether appended porphyrin-fullerene donor acceptor conjugates is demonstrated. Investigations in the seventh chapter involve solubilization of single wall carbon nanotubes by ∏-stacking with pyrene functionalized imidazole or phenyl moieties and subsequent utilization of these nanotubes to build supramolecular donor-acceptor nanohybrids with donors such as porphyrin or napthalocyanine The compounds described in this dissertation were synthesized and characterized by proton NMR and ESI-Mass spectroscopy. Binding constants pertaining to the formation of various complexes were obtained by using UV-visible, fluorescence and ¹H NMR spectral data. Density functional theory (DFT) calculations were performed to gain insight into the structural aspects and orientation of the donor-acceptor groups in these supramolecular complexes. Electrochemical studies were performed to obtain free energy changes for charge separation and charge recombination. Steady state and time resolved fluorescence emission studies in addition to transient absorption studies were employed to obtain charge separation and charge recombination rates and lifetimes of photo-induced electron transfer.
Thesis (Ph.D.)--Wichita State University, College of Liberal Arts and Sciences, Dept. of Chemistry
"December 2007."

The oxidation of three alkyl thioethers, phenol and 2-propanol by trans-dioxo ruthenium porphyrin species, and the synthesis, characterization and reactivity of several new ruthenium porphyrin complexes are described in this thesis. The trans-dioxo species Ru(Porp)(O)₂ [Porp= the dianions of 5,10,15,20-tetramesitylporphyrin (TMP) and 5,10,15,20-(2,6-dichlorophenyl)porphyrin (OCP)] selectively oxidize diethyl-, di-n-butyl- and decylmethyl- sulfides to the corresponding sulfoxides at room temperature. The reaction is first order in [Ru] and in [thioether]. The second order rate constants for the first O-atom transfer from the Ru(TMP) system are: 7.54xl0⁻³, 1.23xl0⁻² and 1.14x10-¹ M⁻¹ s⁻¹ respectively for the three thioethers at 20.0 °C. The activation parameters for the O-atom transfer process are also determined: for Et₂S, ∆H‡= 58.3 kJ mol⁻¹ and ∆S‡= -86 J K⁻¹ mol⁻¹; for nBu₂S, AH‡= 47.4 kJ mol⁻¹and ∆S‡= -120 J K⁻¹ mol⁻¹; for DecMeS, ∆H‡= 56.5 kJ mo⁻¹ and ∆S‡= -70 J K⁻¹ mol⁻¹. A second order rate constant of 7.23xl0⁻²M⁻¹s⁻¹ is measured at 20.0 °C for the oxidation of Et₂S by Ru(OCP)(O)₂. The intermediates Ru(TMP)(OSEt₂)₂, Ru(TMP)(OSEt₂)(OSEt₂) and the final product Ru(TMP)(0SEt₂)₂,where O and S refer to O- and S- bonded sulfoxide, are observed by ¹H nmr, and the last mentioned is isolated and characterized. A mechanism is proposed, based on electrophilic attack of the O=Ru=O moiety on :SR₂ to form bis-O-bonded species which subsequently isomerizes to bis-S-bonded species via mixed species. The Ru(TMP)(O)₂/Et₂S/O₂ system at room temperature is catalytic in complex, but produces only about 5 turnovers due to poisoning of the catalyst by the reaction product. The same system at >65 °C gives higher turnovers, but now porphyrin ligand degradation is observed, perhaps via oxidation by the O=Ru=O moiety. The Ru(OCP)(0)₂/Et₂S/O₂ system at 100 °C catalytically oxidizes Et₂S to Et₂SO and Et₂SO₂ (in ~ 4:1 ratio) and the porphyrin ligand does not undergo oxidative destruction. The Ru(TMP)(O)₂ species reacts with phenol via an observed intermediate Ru(TMP)(p-O(H)C₆H₄OH)₂ to form Ru(IV)(TMP)(OC₆H₄OH)₂, a paramagnetic (S=l) complex which is isolated and characterized. The oxidation reaction is first order in both [Ru] and [phenol] with a second order rate constant 6.90x10⁻² M⁻¹ s⁻¹at 20.0 °C. A mechanism based on electrophilic attack by the O=Ru=O moiety on the aryl ring followed by proton migration is proposed. This mechanism also explains the formation of some free para-benzoquinone and 1 equivalent of water per Ru. No ortho-benzoquinone is formed in the reaction. Preliminary ⁻H nmr studies reveal that 2-propanol is oxidized to acetone by Ru(TMP)(O)₂. A paramagnetic species (S= 1) was isolated as the only porphyrin product but not characterized. A range of novel ruthenium porphyrin complexes is also prepared. The reaction of acetylene with the four-coordinate Ru(TMP) species forms [Ru(TMP)]₂(u-C₂H₂), the first reported organometallic ruthenium porphyrin dimer. The complexes, Ru(TMP)(PhCCPh) and Ru(TMP)(PhCCH), the first π-bonded alkyne species in ruthenium porphyrin chemistry, are characterized in solution. The π-bonded alkene complexes Ru(TMP)(CH₂CH₂) OPrOH).(iPrOH) and Ru(TMP)(CH₂CH₂) are isolated and characterized, while the Ru(TMP)(cyclohexene) complex is characterized in situ. The Ru(TMP)(OSEt₂)₂ complex is isolated also by the reaction of Ru(TMP)(CH₃CN)₂with Et₂SO. The Ru(TMP)(L)₂ complexes, L= OSMe₂, OSnPr₂ and OSnBu₂ are also prepared via the above method and characterized. Some new Ru(OCP) complexes, (the monocarbonyl, the bis-acetonitrile and the dioxo- species) are also isolated and characterized.
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Chemistry, Department of
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