Organophosphates are neurotoxic compounds that inhibit acetylcholinesterase producing excess cholinergic stimulation. This produces various toxic signs including excitotoxic neuronal damage. Oximes can be used as a treatment for organophosphate poisoning by reactivating inhibited acetylcholinesterase. Traditional oximes do not penetrate the blood-brain barrier, limiting protection of the central nervous system. Novel, brain-penetrating oximes have the potential to protect the brain from organophosphate induced damage. Adult male rats were used to examine the ability of model organophosphates to produce neuropathology and the ability of novel oximes to prevent this damage. Additionally, adult male rats were used to examine changes in gene expression of the MAP kinase system resultant of treatment with model organophosphates and novel oximes. Results of these experiments support that the model organophosphates can be used to study neurodegeneration, the novel oximes may prevent neurodegeneration, and both organophosphates and novel oximes affect expression of MAP kinase genes.

This thesis discusses pyridinium bisretinoid compounds (PBRs), which were prepared for two purposes: 1) to use them as standards for detection of novel fluorophores in human RPE cells, which may be involved in age-related macular degeneration (AMD), and 2) to use them in the development of a targeted and triggered drug delivery system for cancer therapy. We prepared a selection of PBRs using a one-pot biomimetic method; synthesis, mechanisms for formation, and characterization of these compounds is described. We also explored the photoreactivity of three novel PBR compounds and found that these PBRs form oxidation products under blue-light irradiation. The photoinduced cytotoxity of A2P and A2EE was examined in HL-60 cells. Results from this work suggest that the PBRs presented have the potential to be involved in AMD and to be developed into a targeted and triggered drug delivery system for cancer therapy.

Hypervalent iodine (HVI) reagents are easily accessed, highly tunable, mild, selective oxidants that are less toxic and more environmentally benign compared to their heavy metal counterparts. λ3-Iodanes, which possess an iodine center bound to one aryl substituent and two heteroatom ligands, have been the subject of recent interest due to their electrophilicity and hypernucleofugality. A central focus of the Wengryniuk laboratory has been the further development and application of a class of electrostatically activated (bis)cationic nitrogen-ligated HVI (N-HVI) reagents. N-HVIs feature datively bound heterocyclic ligands which results in dramatically enhanced electrophilicity and redox potentials. Despite being a highly tunable platform for reagent development, N-HVIs remain a relatively underexplored class of λ3-iodanes. This dissertation focuses on demonstrating N-HVI’s synthetic potential and developing novel variants to enhance their synthetic utility. Chapter 1 of this dissertation serves as a general background and introduction to nitrogen-ligated HVI reagents. Chapter 2 outlines our efforts in N-HVI library expansion, novel syntheses, and characterization. With a library of 33 novel N-HVIs in hand, ligand effects on N-HVI reactivity were analyzed via qualitative and quantitative methods. Chapter 3 describes our first synthetic application of N-HVIs in the development of novel oxidative rearrangements of simple and complex cyclic alcohols. This chapter describes the chemoselective ring expansion of 2° and 3° cyclic alcohols accessing medium-sized cyclic acetal products in good to excellent yields with applicability to Complexity-to-Diversity (CTD) efforts. Chapter 4 demonstrates our initial efforts toward the development of another synthetic method where the functionalized N-heterocyclic ligands of the N-HVIs can be regioselectivity incorporated into a molecule following N-HVI activation of an olefin. The pyridinium lactone salts formed from olefinic acids were isolated in excellent yields via simple trituration, supplying a synthetically useful functional handle that was easily derivatized via known methods. These four chapters summarize the current state of the research with nitrogen-ligated HVI salts, expand upon our initial publications to highlight the development of novel heterocyclic syntheses, and provide a useful guide to further explore the reactivity of these tunable reagents. / Chemistry

Today, drugs are an integral part of healthy human life, with new drug entities being introduced every year in clinic. The advancement of drug development brings complexity and variation, in terms of both physical and chemical properties. Some of these physicochemical characteristics are many times suboptimal, eventually requiring robust delivery systems that can precisely deliver the drugs to the desired tissues. Although many materials have been studied for the generation of drug delivery systems, there is always a need for biomaterials with better properties that can translate into superior delivery systems. In this context, new drug delivery systems that are interface-engineered at materials level for better stability and delivery efficiency in vitro and in vivo are introduced in this dissertation. In the first part of the dissertation, novel oil/water interface-engineered amphiphilic block copolymer micelles that were previously introduced by our lab were assessed for their stability in the presence of various esterase enzymes present in serum and on blood vessel walls, normally encountered by drug delivery systems on route to the targeted tissues. I also assessed the vulnerability of the polymeric micelles in presence of enzymes typically present either inside the tumor cells or secreted in the tumor microenvironment. I revealed the selective stability of empty- and docetaxel-loaded polymeric micelles to enzymatic degradation en route/in tumors and I have correlated this selective stability with polymer structure and interfacial engineering mentioned above. The unique delivery capabilities of interfacial-engineered polymeric micelles were tested in vivo using a mouse model of triple negative breast cancer. We proved that our novel engineered triblock copolymer-based drug delivery systems are superior to similar delivery systems made out of standard diblock copolymer micelles and also to the clinically used Taxotere® formulation towards cancer cell killing and tumor treatment, without displaying any significant toxicity in experimental animals. The second part of the dissertation focuses on the development and assessment of a pyridinium-based pseudo-gemini surfactant that combined the high nucleic acid packaging capacity of pyridinium lipids with the high transfection efficiency of gemini surfactants while displaying a reduced associated cytotoxic effect. I have analyzed the temperature treatment on compaction of nucleic acids into lipoplexes and I have established a high temperature annealing method for this purpose. This novel formulation technique allowed a substantial reduction of the amount of amphiphiles required to compact a specific amount of nucleic acids. This in turn also reduced the cytotoxic effect associated with the use of pyridinium amphiphiles. The effect of inclusion of colipids to lipoplex compaction, the robustness and the transfection efficiency of the lipid/nucleic acid lipoplex systems were assessed in detail, and correlations between formulation composition and biological activity were established. I was also able to show for the first time that pyridinium pseudo-gemini surfactants were able to compact different types of nucleic acids, including pDNA, mRNA and siRNA at lower charge ratios than standard, state-of-the art formulations used for this purposes. I also showed that irrespective to the nucleic acid compacted within the lipoplexes, the novel amphiphiles can efficiently deliver the cargo into the targeted cells even in the presence of very high concentration of serum, a premise for future use of these amphiphiles and formulations in vivo. / Pharmaceutical Sciences

No description available.

Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.

A reação de hidrólise alcalina em fase aquosa de ions N-alquil-4-cianopiridíneos (RCP) foi caracterizada com relação a efeitos de pH, força iônica (&#181;) e constante dielétrica do meio (D) A hidrólise alcalina dos RCP resulta na formação de dois produtos, i.é., a N-alquil-4-carboxiamidopiridíneo (A) e a N-alquil-4-piridona (P) correspondentes. A relação P/A é função crescente de pH e atinge um valor limite de 1,75 para todos os RCP empregados. No entanto, em misturas água/dioxana a formação de P é preferencial. A constante de velocidade observada (k&#968;) de pseudo primeira ordem de hidrólise dos RCP é função de pH. Em solução aquosa (&#181;=0,02) esta dependência pode ser expressa por : log k&#968; = 1,0702 pH - 14,3 Os efeitos devidos a variações em &#181; e D sobre k&#968;, foram analisados segundo os modelos de Debye-Hückel (Robinson, R.A. e Stokes, R.H. em \"Electrolyte Solutions\", 1955) e Brönsted - Christiansen - Scatchard (Amis, E.S. em \"Solven t Effects on Reaction Rates and Mechanisms\", 1966). Os estudos dos efeitos de pH , &#181; e D sobre k&#968; serviram como modelos de referência para racionalizar efeitos de detergentes de vários tipos estruturais tanto na velocidade, como na razão de produtos resultantes da hidrólise alcalina dos RCP. Em soluções tamponadas de micelas de hexadeciltrimetilamônio (CTAB), a k&#968; de hidrólise do íon N-metil-4-cianopiridíneo (MCP) é independente da concentração de detergente. Por outro lado, k&#968; aumenta com CTAB, acima da concentração crítica de micelização (CMC) para íons N-butil (BCP), N-octil (OCP) e N-dodecil-4-cianopiridíneo (DCP) . No caso do DCP o valor máximo de k&#968; na presença de CTAB (k&#968;máx ) é cerca de 200 vêzes maior que k&#968; na ausência de CTAB (k&#968;o). Os dados referentes ao efeito de CTAB para a hidrólise de DCP , foram analisados quantitativamente utilizando o modelo teórico de Troca-Iônica em micelas (Quina, F.H. e Chaimovich, H. J.Phys.Chem. 83,1844 (1979)). Os resultados desta análise indicam que a constante de velocidade de segunda ordem na fase micelar (km2) é uma ordem de magnitude superior àquela na água (ko2). Esta diferença pode ser reproduzida supondo a reação num ambiente com D= 32 e &#181;=3. A adição de dodecilsulfato de sódio (SDS) acima da CMC, inibe a reação. Contudo, não é observada inibição total, mesmo no caso do DCP o qual é completamente incorporado à fase micelar. Empregando a teoria de Troca-Iônica em soluções micelares, explicitas considerações do produto iônico da água na fase micelar (Kw), conduzem a expressões da dependência de concentração de Na+ aquoso (livre) do pH local na superfície do SDS. Análise quantitativa dos resultados de velocidade de hidrólise dos RCP , fornecem o resultado que Kw = 0,025 Kw (kw é o produto iônico da água na fase aquosa), uma vez suposto km2= 10 ko2. Em soluções micelares de 3-(N,N-dimetil-N-dodecilamônio)- propano-l-sulfonato (SDP), k&#968; de hidrólise do DCP aumenta, a razão k máx/ko&#968;; chega a cerca de 15. Esta aceleração pode ser devida a existência de um campo potencial diplar na superfície da micela de SDP. Como no caso de misturas dioxano-água, a razão de produtos P/A em presença de micelas (CTAB, SDS e SDP) refletem a formação preferencial de P. Esta preferência foi analisada considerando os possíveis estados de transição envolvidos. Finalmente descreve-se uma metodologia simples para determinação rápida da homogeneidade dos detergentes derivados de sais de amônio (distribuição do comprimento de cadeias alquila). Esta técnica é em essência uma eliminação micro-Hoffman, devido a direta injeção do detergente na forma de hidróxido e posterior pirólise no cromatógrafo a gás. Como tal, quantidades negligíveis de detergente são requeridas, como também os passos de isolamento e manipulação (e eventuais erros sistemáticos) associados com a eliminação de Hoffman convencional, seguidos por análise no cromatógrafo a gás, são evitados. / The alkaline hydrolysis of N-alkyl-4-cyano pyridinium ions (RCP) in aqueous solution was characterized with respect to the eftects on pH, ionic strength (&#181;) and medium dieletric constant (D) on the reaction. Alkaline hydrolysis of RCP results in the formation of two products, i.e., the corresponding N-alkyl-4-carboxamidopyridinium ion (A) and N-alKyl-4-pyridone (P). In aqueous solution the P/A product ratio increases with pH, attaining a limiting value of 1,75 at high pH for all the RCP. In water-dioxane mixture, however, there is preferential formation of P. The observed pseudo-first-order rate constant (k&#968; ) for hydrolysis of the RCP in aqueous solution (&#181; =0,02) varies with pH according to: LOG k&#968; = 1,0702 pH - 14,3.The effect of changes in &#181; or D on k&#968; were analysed within the framework of the models of Debye-Huckel (Robinson, R.A. and Stockes, R.H. in \"Electrolyte Solutions\", 1955 ) and Brönsted- Christiansen - Scatchard (Amis, E.S. in \"Solvent Effects on Reaction Rates and Mechanisms\", 1966) . These dependences of k&#968; and of the P/A product ratio on pH, &#181; and D served as a basis for rationalization of the effects of detergents of various structural types on both the rate of alkaline hydrolysis of the RCPand the resultant produc ratio. In Buffered micellar solutions o hexadecyltrimethylammonium bromide (CTAB), k&#968; for alkaline hydrolysis of the N-methyl-4-cyanopyridinium ion (MCP) is independent of detergent concentration. In contrast, k&#968; increases with (CTAB) above the critical micelle concentration (CMC) for the N-Butil (BCP), N-octyl (OCP) and N-dodecyl-4 cyanopyrydinium (DCP) ions. In the case of DCP, the maximum value of k&#968; in the presence of CTAB (k&#968; max) is 200 times greater than k&#968; in the absence of CTAB (ko&#968; ). The effect of CTAB on k&#968; for alkaline hydrolysis of DCP was analyzed quantitatively using the conceptual model for ion exchange (Quina, F.H. and Chaimovich, H. J.Phys.Chem. 83, 1844 (1979)). The results of this analysis indicate that the second order rate constant for hydrolysis in the micellar phase (km2) is an order of magnitude greater than that in the aqueous phase (ko<sub2). This difference betwen km2 and ko2 can be reproduced by assuming a reaction environment with D=32 and &#181; = 3. Micellar sodium dodecyl sulfate (SDS) inhibit the rate of alkaline hydrolysis of all the RCP. Nonetheless, total inhibition is not observed, even in the case of DCP, which is completely incorporated into the micellar phase. Using the theory of ion exchange in micellar solutions, explicitly consideration of the ionic product of water in the micellar phase (Kw) leads to expression for the external (free) N+a dependence of the local pH at the SDS micellar surface. Quantitative analysis of the rate data for the alkaline hydrolysis of the RCP, assuming km2= 10 ko2, furnishes the result that Kw= 0,025 Kw, where Kw is the product of water in the aqueous phase.In micellar solutians of 3-(N,N-dimethyl-N-dodecylammonium) propane-l-sulfanate (SDP), k&#968; for alkalyne Hydrolysisof DCP increases, the ratia k&#968;max/ko&#968; attaining a value of ca. 15. The observed rate acceleration is suggested to be due to the existence of a dipolar potencial field at the SDP micellar surface. As in the case of water-dioxane mixtures, the P/A product ratio in the presence of detergent micelles (CTAB, SDS and SDP) reflects preferential formation of P. This preference was analyzed on the basis of considerations of possible transition states involved. Finally, a simple methodology for rapid determination of the homogeneity (distribution of alkyl chain lengths) of ammonium-derived detergents is described. This technique is in essence a micro Hoffmannelimination effected by direct injection pyrolysis glpc of the detergent in the hydroxide form. As small negligible quantities of detergent are required and the product isolation and manipulation steps and attendant systematic errors) associated with a conventional Hoffmannelimination, followed by glpc analysis of the products are circunve ted.

Un composé de type N-aryle pyridinium (PF) a montré un réel potentiel en tant qu’inducteur chimique de la maladie de Parkinson (MP). Son administration in vitro et in vivo a permis d’induire l’apparition des marqueurs cellulaires caractéristiques de la MP mais suivant une cinétique d’action beaucoup plus lente que les inducteurs parkinsoniens actuellement disponibles. Ces travaux préliminaires ont suggéré l’existence d’un lien entre le motif N-aryle pyridinium et la capacité pour la molécule qui le porte à induire chimiquement la MP. Ces résultats ont dès lors laissé envisager la préparation de composés structurellement inspirés, capables de mimer plus fidèlement les mécanismes biochimiques impliqués lors de l’apparition de la MP. Partant du même composé de départ – un dérivé de l’aniline – deux voies de synthèse ont été suivies et ont permis d’aboutir à des N-aryle pyridiniums diversement fonctionnalisés. La première voie d’accès, exploitant la réaction de Zincke, a permis d’aboutir à des composés ne portant pas de groupement hydroxyle sur le noyau pyridinium. La deuxième voie d’accès, comprenant une étape-clé d’activation anodique et inspirée de la préparation du PF, a permis d’aboutir à des N-aryle pyridiniums 3-hydroxylés. Pour ces deux voies de synthèse, la nature du composé de départ a contraint à la modification des protocoles opératoires décrits dans la littérature afin de pouvoir accéder aux molécules ciblées. L’évaluation toxicologique de ces N-aryle pyridiniums a donné lieu à une étude de relation structure/activité. Les résultats de cette étude ont permis d’identifier les éléments structuraux permettant à la fois l’inhibition du complexe I de la chaine respiratoire mitochondriale et l’induction d’une neurotoxicité in vitro. Il a également été possible d’identifier, pour la première fois, un paramètre permettant la modulation de la pénétration cellulaire dopaminergique et par suite, de l’activité de ces inducteurs chimiques de la MP / A N-aryl pyridinium derivative (PF) has shown promising results as a chemical inducer of Parkinson's disease (PD). Its in vitro and in vivo administration has induced the appearance of characteristical cellular markers of PD but following a much slower kinetics than currently available PD inducers. These preliminary studies have suggested the existence of a link between the N-aryl pyridinium moiety and the ability of the molecule bearing it to chemically induce PD. These results have therefore led to the preparation of structurally related compounds, able to mimic more closely the biochemical mechanisms involved in the onset of PD.Using the same starting material - an aniline derivative - two synthetic pathways have been followed and have led to diversely functionalized N-aryl pyridiniums. The first pathway, based on the Zincke reaction, afforded compounds without hydroxyl group on the pyridinium ring. The second pathway, including a key step of anodic activation and inspired the preparation of PF, led to 3-hydroxy-N-aryl pyridiniums. For both synthetic routes, the nature of the starting material has implied the modification of previously protocols described to gain access to the targeted molecules. The toxicological evaluation of these N-aryl pyridiniums gave rise to a structure / activity relationship study. The results of this study have led to the identification of structural elements allowing both the inhibition of complex I of the mitochondrial respiratory chain and the induction of in vitro neurotoxicity. It was also possible to identify for the first time, a parameter for the modulation of dopaminergic cell penetration and hence the activity of these chemical inducers of PD

A reação de hidrólise alcalina em fase aquosa de ions N-alquil-4-cianopiridíneos (RCP) foi caracterizada com relação a efeitos de pH, força iônica (&#181;) e constante dielétrica do meio (D) A hidrólise alcalina dos RCP resulta na formação de dois produtos, i.é., a N-alquil-4-carboxiamidopiridíneo (A) e a N-alquil-4-piridona (P) correspondentes. A relação P/A é função crescente de pH e atinge um valor limite de 1,75 para todos os RCP empregados. No entanto, em misturas água/dioxana a formação de P é preferencial. A constante de velocidade observada (k&#968;) de pseudo primeira ordem de hidrólise dos RCP é função de pH. Em solução aquosa (&#181;=0,02) esta dependência pode ser expressa por : log k&#968; = 1,0702 pH - 14,3 Os efeitos devidos a variações em &#181; e D sobre k&#968;, foram analisados segundo os modelos de Debye-Hückel (Robinson, R.A. e Stokes, R.H. em \"Electrolyte Solutions\", 1955) e Brönsted - Christiansen - Scatchard (Amis, E.S. em \"Solven t Effects on Reaction Rates and Mechanisms\", 1966). Os estudos dos efeitos de pH , &#181; e D sobre k&#968; serviram como modelos de referência para racionalizar efeitos de detergentes de vários tipos estruturais tanto na velocidade, como na razão de produtos resultantes da hidrólise alcalina dos RCP. Em soluções tamponadas de micelas de hexadeciltrimetilamônio (CTAB), a k&#968; de hidrólise do íon N-metil-4-cianopiridíneo (MCP) é independente da concentração de detergente. Por outro lado, k&#968; aumenta com CTAB, acima da concentração crítica de micelização (CMC) para íons N-butil (BCP), N-octil (OCP) e N-dodecil-4-cianopiridíneo (DCP) . No caso do DCP o valor máximo de k&#968; na presença de CTAB (k&#968;máx ) é cerca de 200 vêzes maior que k&#968; na ausência de CTAB (k&#968;o). Os dados referentes ao efeito de CTAB para a hidrólise de DCP , foram analisados quantitativamente utilizando o modelo teórico de Troca-Iônica em micelas (Quina, F.H. e Chaimovich, H. J.Phys.Chem. 83,1844 (1979)). Os resultados desta análise indicam que a constante de velocidade de segunda ordem na fase micelar (km2) é uma ordem de magnitude superior àquela na água (ko2). Esta diferença pode ser reproduzida supondo a reação num ambiente com D= 32 e &#181;=3. A adição de dodecilsulfato de sódio (SDS) acima da CMC, inibe a reação. Contudo, não é observada inibição total, mesmo no caso do DCP o qual é completamente incorporado à fase micelar. Empregando a teoria de Troca-Iônica em soluções micelares, explicitas considerações do produto iônico da água na fase micelar (Kw), conduzem a expressões da dependência de concentração de Na+ aquoso (livre) do pH local na superfície do SDS. Análise quantitativa dos resultados de velocidade de hidrólise dos RCP , fornecem o resultado que Kw = 0,025 Kw (kw é o produto iônico da água na fase aquosa), uma vez suposto km2= 10 ko2. Em soluções micelares de 3-(N,N-dimetil-N-dodecilamônio)- propano-l-sulfonato (SDP), k&#968; de hidrólise do DCP aumenta, a razão k máx/ko&#968;; chega a cerca de 15. Esta aceleração pode ser devida a existência de um campo potencial diplar na superfície da micela de SDP. Como no caso de misturas dioxano-água, a razão de produtos P/A em presença de micelas (CTAB, SDS e SDP) refletem a formação preferencial de P. Esta preferência foi analisada considerando os possíveis estados de transição envolvidos. Finalmente descreve-se uma metodologia simples para determinação rápida da homogeneidade dos detergentes derivados de sais de amônio (distribuição do comprimento de cadeias alquila). Esta técnica é em essência uma eliminação micro-Hoffman, devido a direta injeção do detergente na forma de hidróxido e posterior pirólise no cromatógrafo a gás. Como tal, quantidades negligíveis de detergente são requeridas, como também os passos de isolamento e manipulação (e eventuais erros sistemáticos) associados com a eliminação de Hoffman convencional, seguidos por análise no cromatógrafo a gás, são evitados. / The alkaline hydrolysis of N-alkyl-4-cyano pyridinium ions (RCP) in aqueous solution was characterized with respect to the eftects on pH, ionic strength (&#181;) and medium dieletric constant (D) on the reaction. Alkaline hydrolysis of RCP results in the formation of two products, i.e., the corresponding N-alkyl-4-carboxamidopyridinium ion (A) and N-alKyl-4-pyridone (P). In aqueous solution the P/A product ratio increases with pH, attaining a limiting value of 1,75 at high pH for all the RCP. In water-dioxane mixture, however, there is preferential formation of P. The observed pseudo-first-order rate constant (k&#968; ) for hydrolysis of the RCP in aqueous solution (&#181; =0,02) varies with pH according to: LOG k&#968; = 1,0702 pH - 14,3.The effect of changes in &#181; or D on k&#968; were analysed within the framework of the models of Debye-Huckel (Robinson, R.A. and Stockes, R.H. in \"Electrolyte Solutions\", 1955 ) and Brönsted- Christiansen - Scatchard (Amis, E.S. in \"Solvent Effects on Reaction Rates and Mechanisms\", 1966) . These dependences of k&#968; and of the P/A product ratio on pH, &#181; and D served as a basis for rationalization of the effects of detergents of various structural types on both the rate of alkaline hydrolysis of the RCPand the resultant produc ratio. In Buffered micellar solutions o hexadecyltrimethylammonium bromide (CTAB), k&#968; for alkaline hydrolysis of the N-methyl-4-cyanopyridinium ion (MCP) is independent of detergent concentration. In contrast, k&#968; increases with (CTAB) above the critical micelle concentration (CMC) for the N-Butil (BCP), N-octyl (OCP) and N-dodecyl-4 cyanopyrydinium (DCP) ions. In the case of DCP, the maximum value of k&#968; in the presence of CTAB (k&#968; max) is 200 times greater than k&#968; in the absence of CTAB (ko&#968; ). The effect of CTAB on k&#968; for alkaline hydrolysis of DCP was analyzed quantitatively using the conceptual model for ion exchange (Quina, F.H. and Chaimovich, H. J.Phys.Chem. 83, 1844 (1979)). The results of this analysis indicate that the second order rate constant for hydrolysis in the micellar phase (km2) is an order of magnitude greater than that in the aqueous phase (ko<sub2). This difference betwen km2 and ko2 can be reproduced by assuming a reaction environment with D=32 and &#181; = 3. Micellar sodium dodecyl sulfate (SDS) inhibit the rate of alkaline hydrolysis of all the RCP. Nonetheless, total inhibition is not observed, even in the case of DCP, which is completely incorporated into the micellar phase. Using the theory of ion exchange in micellar solutions, explicitly consideration of the ionic product of water in the micellar phase (Kw) leads to expression for the external (free) N+a dependence of the local pH at the SDS micellar surface. Quantitative analysis of the rate data for the alkaline hydrolysis of the RCP, assuming km2= 10 ko2, furnishes the result that Kw= 0,025 Kw, where Kw is the product of water in the aqueous phase.In micellar solutians of 3-(N,N-dimethyl-N-dodecylammonium) propane-l-sulfanate (SDP), k&#968; for alkalyne Hydrolysisof DCP increases, the ratia k&#968;max/ko&#968; attaining a value of ca. 15. The observed rate acceleration is suggested to be due to the existence of a dipolar potencial field at the SDP micellar surface. As in the case of water-dioxane mixtures, the P/A product ratio in the presence of detergent micelles (CTAB, SDS and SDP) reflects preferential formation of P. This preference was analyzed on the basis of considerations of possible transition states involved. Finally, a simple methodology for rapid determination of the homogeneity (distribution of alkyl chain lengths) of ammonium-derived detergents is described. This technique is in essence a micro Hoffmannelimination effected by direct injection pyrolysis glpc of the detergent in the hydroxide form. As small negligible quantities of detergent are required and the product isolation and manipulation steps and attendant systematic errors) associated with a conventional Hoffmannelimination, followed by glpc analysis of the products are circunve ted.

Age-related macular degeneration (AMD) is the leading cause of blindness in the United States of America. The pyridinium bis-retinoid A2-ethanolamine (A2E) has been implicated to play a role in AMD. We have observed novel pyridinium bis-retinoids through melanolipofuscin and human RPE extractions that may also play a role in the pathology of AMD. We have begun the construction of an amino-retinoid library in order to identify these ocular compounds. The compounds from the amino-retinoid library are also used in a targeted and triggered drug delivery system for treating cancer. Folic acid is coupled with the amino-retinoids to specifically target cancer cells. The first two amino-retinoids to be synthesized and characterized were A2-dopamine (A2D) and A2-cadaverine (A2C). Both pyridinium bis-retinoids were shown to generate cytotoxic oxidation products similar to A2E. Successful coupling of folic acid to A2C was achieved to form the folic acid-A2-cadaverine (FA-A2C) product. Preliminary irradiation results suggest that the FA-A2C product may be more photoreactive than initially anticipated. This could mean less drug and light exposure required to induce apoptosis and could eventually lead to a less invasive and toxic cancer treatment.