An approach to the total synthesis of novel opiate and Amaryllidaceae alkaloids is described. A rapid and efficient construction of the key intermediate [1.83], employing a palladium mediated cyclisation is presented. Studies towards the opiate ring skeleton utilising both nitrone and nitrile oxide [3+2] cycloadditions is investigated. Synthesis of the Amaryllidaceae alkaloids ring structure is described, involving a novel sublimation cyclisation protocol. The total synthesis of N, O-dimethyl norsanguinine is presented.

Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.

Not available / text

The opiate alkaloid (-)-morphine and the Amaryllidaceae alkaloid (-)-galanthamine are well known for their analgesic and anticholinergic properties, respectively. The chemical feature that connects these two molecules is that they are both biosynthesized from an ortho-para phenolic oxidative coupling. Attempts to mimic this aesthetic chemistry in the laboratory for the practical production of these alkaloids have not resulted in good yields of these compounds and there is a lot of scope for improvement. Despite the enormous amount of work devoted to this area, the simple para-alkylation of an appropriately substituted phenol derivative to generate a cross conjugated 2, 5-cyclohexadienone has not been reported. This strategy would avoid the low-yielding phenolic oxidation reaction and the product would merely require a double reductive amination of the aromatic aldehyde and the latent aldehyde (in the acetal) to produce narwedine, the synthetic precursor to (-)-galanthamine. On the other hand, the same intermediate can be elaborated to (±)-morphine via a Henry reaction, followed by reduction and reductive amination. Following the aforementioned methodology, we have successfully completed the synthesis of both these alkaloids via the common intermediate, a 2, 5-cross-conjugated cyclohexadienone. A demonstration of the use of this methodology towards achieving an enantioselective synthesis of these compounds has also been made. The overall yield of the 8 step procedure for galanthamine proceeds in 65% yield, which is approximately five times the yield of the current manufacturing process for this molecule. The synthesis of (±)-morphine, for the first time, allows access to codeine without having to reduce codeinone and, with an overall yield of 20% for the 14 step process, makes this the shortest synthesis of morphine. / text

Galanthamine is one of only a few drugs that is licenced for the treatment of Alzheimer's disease. It is manufactured through an inefficient synthetic process or extracted from members of the Amaryllidaceae plant family. In this work a range of structurally related alkaloids was semisynthesised from galanthamine and used as standards to assist with the search for alkaloids that may make a good starting point in the semisynthesis of galanthamine. The search was targeted on the effluent from the production line of Alzeim Ltd., a company that extracted galanthamine from members of the Narcissus genus. In addition to the above there was an examination of specific areas of galanthamine chemistry; focusing on the application of synthetic methodologies to open new chemical space. By far the most successful of these was the use of galanthamine in a urea-mediated intramolecular aryl migration. A rare example of lithiation chemistry being applied to a natural product and also the most complicated structure to date on which the intramolecular aryl migration has been performed.

La galanthamine est un alcaloïde isoquinoléique, utilisé dans le monde entier pour le traitement palliatif de la maladie d’Alzheimer en raison de son pouvoir inhibiteur de l’acétylcholinestérase. Cet alcaloïde est extrait à partir de bulbes d’Amaryllidaceae, Leucojum aestivum, Galanthus nivalis, et Narcissus sp. ou obtenu par synthèse chimique. La difficulté principale de cette dernière réside dans le respect de la configuration des centres d'asymétrie. La culture de tissus in vitro pourrait constituer une alternative intéressante pour obtenir ce composé à haute valeur ajoutée. Le premier objectif de ce projet, vise à améliorer l’accumulation de cet alcaloïde par les biais des biotechnologies. Le second objectif est de rechercher par criblage phytochimique (HPLC, LCMS, GCMS, et HPTLC-MS) de bulbes in vitro et in vivo d’Amaryllidaceae, de nouveaux alcaloïdes biologiquement actifs. Le troisième objectif porte sur l’étude de la voie de biosynthèse en vue de réaliser une synthèse biomimétique de la galanthamine. Nous avons établi des cultures in vitro de 3 espèces d’Amaryllidaceae. La variation des paramètres exogènes a conduit à une accumulation accrue d’alcaloïdes (0,02 à 0,2 % MS). Le criblage phytochimique a conduit à l’identification d’alcaloïdes nouveaux issus des cultures in vitro, n’existant pas in vivo, et présentant un puissant pouvoir inhibiteur de l’acétylcholinestérase (40 à 80 % Inh). L’ajout, de la 4’-Ométhyl-d3-norbelladine aux cultures in vitro a conduit à sa métabolisation en trois types d’alcaloïdes deutérés. Une stimulation de la synthèse et du relargage de la galanthamine native (0,15 % MS et 0,16 % Milieu) a été observée en présence du précurseur deutéré / Galanthamine is an Amaryllidaceae alkaloid used worldwide for the symptomatic treatment of Alzheimer’s disease because of his capacity to inhibit the acetylcholinesterase enzyme. There are two galanthamine sources for medical applications. One is the total synthesis, a complicated process because galanthamine has three asymmetric carbons, requiring stereochemically controlled synthesis. Galanthamine is also extracted from bulbs of some Amaryllidaceae such as Leucojum aestivum, Galanthus nivalis, and Narcissus sp.. The first aim of this work is to improve the accumulation of this alkaloid using biotechnologies. The second aim consists on the phytochemical screening (HPLC, LCMS, GCMS, et HPTLCMS) of in vivo and in vitro Amaryllidaceae bulbs, in order to identify new alkaloids with important pharmacological activities. Finally, the third aim concerns the study of the biosynthesis pathway in order to establish a biomimetic synthesis of galanthamine. Therefore, we established in vitro cultures of three Amaryllidaceae species. The variation of exogenousparameters led to the obtainment of high galanthamine accumulation (0.02 to 0.2 % DW). The phytochemical screening showed new alkaloids in extracts of in vitro cultures, which did not exist in in vivo extracts, and possessing high acetylcholinesterase activity (40 to 80 % Inh). The 4’-O-methyl-d3-norbelladine is incorporated into three different groups ofAmaryllidaceae alkaloids. The addition of the labelled precursor to shoot cultures stimulated the synthesis of native galanthamine (0.15 % DW and 0.16 % Culture medium)

A Doença de Alzheimer (DA) é o tipo mais comum de demência em idosos, a etiologia é multifatorial e a fisiopatologia da doença é complexa, com um novo caso acontecendo a cada sete segundos; globalmente, a doença está se tornando em uma lenta pandemia. Bioquimicamente, a DA é caracterizada pela presença das placas neuríticas (PNs) e os novelos neurofibrilares (NNFs). O peptídeo beta peptide1-42 (A?(1-42)) é o principal componente das placas neuríticas e tem sido fortemente associado ao estresse oxidativo, desregulação colinérgica e morte celular. Os múltiplos mecanismos envolvidos na patogênese criam consideráveis dificuldades para identificar alvos terapêuticos apropriados. As abordagens terapêuticas atuais melhoram temporariamente os sintomas da DA; no entanto, apesar de esforços intensivos, nenhum dos tratamentos disponíveis hoje conseguiu alterar o curso da doença. Porém, algumas das terapias mais relevantes para o tratamento da doença estão baseadas na atividade inibidora da acetilcolinesterase (AChE). Nos últimos anos, os alcaloides pertencentes à família Amaryllidaceae têm recebido muita atenção devido à atividade anticolinérgica e antioxidante. A galantamina foi o primeiro alcaloide isolado a partir de diferentes espécies de Amaryllidaceas e é o mais recente inibidor da AChE aprovado para o tratamento sintomático da DA. Este fato tem motivado a pesquisa de outros alcaloides como possíveis moduladores da doença em adição à atividade inibitória da AChE. Diante disso, o objetivo deste estudo foi investigar se o extrato de Caliphruria subedentata e a galantamina modulam a neurotoxicidade induzida pelo A?(1-42) na linhagem celular SH-SY5Y indiferenciada. Para compreender os mecanismos de neuroproteção, um conjunto de ensaios foi realizado tais como atividade inibitória da AChE, ensaios clonogênico, micronúcleos com bloqueio na citocinese celular (CBMNcyt), cometa; análises por microscopia eletrônica de transmissão (MET) e de metilação. Os resultados mostraram que tanto o extrato quanto a galantamina diminuíram significativamente a citotoxicidade e genotoxicidade induzida pelo A?(1-42). Além disso, ambos os tratamentos modularam alterações morfológicas mitocondriais induzidas pelo peptídeo. Em conclusão, os resultados deste estudo demonstraram que, em adição à atividade inibitória da AChE, tanto o extrato de C. subedentata quanto a galantamina exercem propriedades antigenotóxicas. Essas propriedades relevantes da Amaryllidaceaes e o fármaco tornam-se um potencial valioso para continuar sendo explorado. / Alzheimer´s disease (AD) is the most common type of dementia in elderly population, the etiology is multifactorial and the pathophysiology of the disease is complex, with a new case occurring every seven seconds; globally, the disease itself is becoming a slowly pandemic. Biochemically, the AD is characterized by presence of the neuritic plaques and neurofibrillary tangles. Amyloid beta peptide1-42 (A?(1-42)) is the principal component of neuritic plaques and it has been strongly associated with oxidative stress, cholinergic deregulation and cell death. The multiple mechanisms involved in the pathogenesis create considerable difficulty to identify appropriate targets. The current therapeutics approaches for AD improve temporally the symptoms; and despite intensive efforts, none of the treatments available today alter the course of disease. Nervertheless, some of the most relevant therapies for the treatment of disease are based on acetylcholinesterase (AChE) inhibitor activity. In recent years, alkaloids belonging Amaryllidaceae family have received great attention due to the well-known anticholinergic and antioxidant activity and the galanthamine was the first alkaloid isolated from different species of Amaryllidacea and it is the most recently AChE inhibitor approved for the symptomatic treatment of AD. This fact has motivated the screening of other alkaloids as possible modulators of disease in addition acetylcholinesterase activity. Purpose this study was to investigate whether C. subedentata extract and galanthamine modulate A?(1-42)- induced neurotoxicity in the undifferentiated SH-SY5Y cell line. To understand the mechanisms of the neuroprotection, a set of biomarkers such as AChE activity, clonogenic, cytokinesis block micronucleus cytome (CBMNcyt) and comet assays; beside transmission electron microscope (TEM) and methylation analyses were realized. The results showed that C. subedentata extract and galanthamine were capable to significantly reduce the A?(1-42)- induced cytotoxicity and genotoxicity. Furthermore both treatments modulated A?(1-42)- induced mitochondrial morphological alterations. In conclusion, this study demonstrated that in addition to inhibition of acetylcholinesterase (AChE), the extract of C. subedentata and galanthamine exert antigenotoxic properties. This relevant property of Amaryllidaceaes and galanthamine are worthwhile exploring further which may improve the development of new diseases-modifying agents.

Plus de 300 alcaloïdes d’Amaryllidaceae doués d’activités biologiques ont été isolés à partir des plantes appartenant à cette famille. De nos jours, seule la galanthamine, utilisée pour le traitement palliatif de la maladie d’Alzheimer, est commercialisée. L’accumulation de ces alcaloïdes dans les plantes est limitée. La culture in vitro est une méthode alternative intéressante pour l’obtention plus aisée de ces alcaloïdes à haute valeur ajoutée. Le premier objectif de ce travail vise à développer une méthode de purification efficace, simple et rapide des extraits de plantes préalablement à leur analyse en LCMS et GCMS. Le second objectif est d’étudier l’effet de plusieurs facteurs exogènes, ajoutés au milieu de culture de bulbilles de Leucojum aestivum et de sa variété Gravety Giant en bioréacteurs RITA®, sur les voies de biosynthèse de la galanthamine et de la lycorine. La variation des paramètres exogènes a permis une accumulation accrue en galanthamine et en lycorine (0,814 mg/g et 1,54 mg/g de matière sèche respectivement) dans les bulbilles. Le troisième objectif porte sur l’isolement et l’identification d’endophytes à partir de bulbes in vivo et in vitro de trois espèces d’Amaryllidaceae (L. aestivum, Narcissus pseudonarcissus et Galanthus elwesii). Des bactéries endophytes du genre Bacillus ont été identifiées. Un nouvel alcaloïde a été isolé à partir des cultures bactériennes / Over 300 Amaryllidaceae alkaloids possessing a wide range of biological activities have been isolated from plants belonging to this family. Galanthamine, used for the palliative treatment of Alzheimer’s disease, is the only one commercialized. The biodisponiblity of these alkaloids is low. In vitro culture offers an alternative yet interesting approach for the biotechnological production of these valuable alkaloids. The aim of this work was, first, to develop a fast, efficient and easy purification method of plant extracts prior to their phytochemical analysis both in LCMS and GCMS. Second, the combined effects of bioreactor RITA® culture and feeding with different exogenous factors on the biosynthetic pathway of both galanthamine and lycorine were studied. The experiments were conducted both with Leucojum aestivum and L. aestivum ‘Gravety Giant’ bulblets. The variation of several exogenous parameters resulted in a better accumulation of galanthamine and lycorine (0.814 mg/g and 1.54 mg/g dry weight respectively) in the bulblets. The third aim was to isolate and identify alkaloid producing endophytes from in vivo and in vitro bulbs of three Amaryllidaceae species (L. aestivum, Narcissus pseudonarcissus and Galanthus elwesii). Bacterial endophtes belonging to the Bacillus genus were identified. A new alkaloid was isolated from bacterial liquid cultures

A Doença de Alzheimer (DA) é o tipo mais comum de demência em idosos, a etiologia é multifatorial e a fisiopatologia da doença é complexa, com um novo caso acontecendo a cada sete segundos; globalmente, a doença está se tornando em uma lenta pandemia. Bioquimicamente, a DA é caracterizada pela presença das placas neuríticas (PNs) e os novelos neurofibrilares (NNFs). O peptídeo beta peptide1-42 (A?(1-42)) é o principal componente das placas neuríticas e tem sido fortemente associado ao estresse oxidativo, desregulação colinérgica e morte celular. Os múltiplos mecanismos envolvidos na patogênese criam consideráveis dificuldades para identificar alvos terapêuticos apropriados. As abordagens terapêuticas atuais melhoram temporariamente os sintomas da DA; no entanto, apesar de esforços intensivos, nenhum dos tratamentos disponíveis hoje conseguiu alterar o curso da doença. Porém, algumas das terapias mais relevantes para o tratamento da doença estão baseadas na atividade inibidora da acetilcolinesterase (AChE). Nos últimos anos, os alcaloides pertencentes à família Amaryllidaceae têm recebido muita atenção devido à atividade anticolinérgica e antioxidante. A galantamina foi o primeiro alcaloide isolado a partir de diferentes espécies de Amaryllidaceas e é o mais recente inibidor da AChE aprovado para o tratamento sintomático da DA. Este fato tem motivado a pesquisa de outros alcaloides como possíveis moduladores da doença em adição à atividade inibitória da AChE. Diante disso, o objetivo deste estudo foi investigar se o extrato de Caliphruria subedentata e a galantamina modulam a neurotoxicidade induzida pelo A?(1-42) na linhagem celular SH-SY5Y indiferenciada. Para compreender os mecanismos de neuroproteção, um conjunto de ensaios foi realizado tais como atividade inibitória da AChE, ensaios clonogênico, micronúcleos com bloqueio na citocinese celular (CBMNcyt), cometa; análises por microscopia eletrônica de transmissão (MET) e de metilação. Os resultados mostraram que tanto o extrato quanto a galantamina diminuíram significativamente a citotoxicidade e genotoxicidade induzida pelo A?(1-42). Além disso, ambos os tratamentos modularam alterações morfológicas mitocondriais induzidas pelo peptídeo. Em conclusão, os resultados deste estudo demonstraram que, em adição à atividade inibitória da AChE, tanto o extrato de C. subedentata quanto a galantamina exercem propriedades antigenotóxicas. Essas propriedades relevantes da Amaryllidaceaes e o fármaco tornam-se um potencial valioso para continuar sendo explorado. / Alzheimer´s disease (AD) is the most common type of dementia in elderly population, the etiology is multifactorial and the pathophysiology of the disease is complex, with a new case occurring every seven seconds; globally, the disease itself is becoming a slowly pandemic. Biochemically, the AD is characterized by presence of the neuritic plaques and neurofibrillary tangles. Amyloid beta peptide1-42 (A?(1-42)) is the principal component of neuritic plaques and it has been strongly associated with oxidative stress, cholinergic deregulation and cell death. The multiple mechanisms involved in the pathogenesis create considerable difficulty to identify appropriate targets. The current therapeutics approaches for AD improve temporally the symptoms; and despite intensive efforts, none of the treatments available today alter the course of disease. Nervertheless, some of the most relevant therapies for the treatment of disease are based on acetylcholinesterase (AChE) inhibitor activity. In recent years, alkaloids belonging Amaryllidaceae family have received great attention due to the well-known anticholinergic and antioxidant activity and the galanthamine was the first alkaloid isolated from different species of Amaryllidacea and it is the most recently AChE inhibitor approved for the symptomatic treatment of AD. This fact has motivated the screening of other alkaloids as possible modulators of disease in addition acetylcholinesterase activity. Purpose this study was to investigate whether C. subedentata extract and galanthamine modulate A?(1-42)- induced neurotoxicity in the undifferentiated SH-SY5Y cell line. To understand the mechanisms of the neuroprotection, a set of biomarkers such as AChE activity, clonogenic, cytokinesis block micronucleus cytome (CBMNcyt) and comet assays; beside transmission electron microscope (TEM) and methylation analyses were realized. The results showed that C. subedentata extract and galanthamine were capable to significantly reduce the A?(1-42)- induced cytotoxicity and genotoxicity. Furthermore both treatments modulated A?(1-42)- induced mitochondrial morphological alterations. In conclusion, this study demonstrated that in addition to inhibition of acetylcholinesterase (AChE), the extract of C. subedentata and galanthamine exert antigenotoxic properties. This relevant property of Amaryllidaceaes and galanthamine are worthwhile exploring further which may improve the development of new diseases-modifying agents.

[pt] O destino e os efeitos de produtos farmacêuticos recentemente se tornou uma questão de interesse ambiental embora pouco seja conhecido sobre sua entrada no ambiente. As drogas colinérgicas e colinesterásicas apresentam-se como um alvo importante da pesquisa ambiental relacionado a sua entrada no ambiente e suas interações físico-químicas e biológicas. Os ensaios com uso de à sondas protéicas são empregados para identificar a formação de complexos na presença de grupos específicos ou indicam a concentração de ligantes presente no ambiente onde se encontra a proteína. O emprego da enzima acetilcolinesterase (AChE) em biosensores para deterninação de inibidores é frequente porém poucos trabalhos exploram a fluorescência intrínseca das enzimas no desenvolvimento de metodologias para detectar espécies químicas ligantes. O objetivo deste trabalho foi propor novas sondas fluorescentes e formas de bioreconhecimento para a determinação de neurotoxinas em diferentes amostras. A proposta foi a de identificar sondas eficientes, de fácil obtenção e baixo custo para o desenvolvimento de métodos simples, sensíveis e seletivos. Para isso a detecção foi baseada na variação da fluorescência intrínseca das proteínas(por sua interação específica com os analitos) e na conjugação de fluoróforos extrínsecos específicos. Pode-se comprovar experimentalmente que a fração protéica obtida pode ser utilizada como sonda fluorescente na determinação dos analitos apresentados neste estudo. Nas determinações dos cinco analitos, os valores de LD e de LQ foram satisfatórios para a aplicação do método em amostras ambientais (solo) e clínicas (urina).As determinações de Gal apresentou desempenho satisfatório para atender diferentes tipos de amostras (LD = 1,3 x 10-9 mol L-1e LQ = 2,1 x 10-8 mol L-1).Os valores de LD e LQ para atropina (9,7 x 10-10 mol L-1 e 2,4 x 10-8 mol L-1, respectivamente) mostram-se adequados visto que outros sensores, como os eletroquimioluminescentes, apresentaram um valor de LQ de 1 × 10–7 mol L-1em amostras de urina. O método para os agrotóxicos metomil (LD = 9,5 x 10-10 mol L-1 e LQ = 2,2 x 10-8mol L-1); metamidofós (LD=1,5 x 10-9 mol L-1 e LQ=3,8 x 10-8 mol L-1) e metil paration (LD= 9,7 x 10-10 mol L-1 e LQ= 1,8 x 10-7 mol L-1) apresentarambom desempenho comparando-se à outros métodos descritos na literatura. A aplicação do método proposto em amostras de solo e urina (sem pré-tratamento) obtiveram recuperações a partir de 88 porcento (agrotóxicos em solo) e dos cinco analitos em urina. O método por fluorescência da sonda protéica não obteve diferença significativa do método analítico dos analitos por HPLC. A adaptação do método proposto à um sistema de biosensor com uso de uma sonda extrínseca (Tioflavina T) foi avaliado positivamente permitindo a imobilização da fração protéica em microplaca e o uso da Tioflavina T como sonda fluorescente da ligação AChE-inibidores. / [en] The fate and effects of pharmaceutical products has recently become a matter of environmental concern although little is known about its entry into the environment. Therefore, the cholinergic and cholinesterasicpresent a major target of environmental research related to his entry into the environment and their physico-chemical and biological interactions. Tests using the protein compounds as probes are employed where the optical properties of the complex protein-signal in the presence of analyte or specific groups indicating the concentration of ligand present in the environment. The use of acetylcholinesterase (AChE) activity in biosensors for inhibitors determination is common but few studies explore the intrinsic fluorescence of enzymes in the development of methods to detect chemical species ligands. The objective of this study was to propose new forms of fluorescent probes and bioaffinity for the determination of neurotoxins in different samples. The proposal was to identify probes efficient, easily accessible and low cost for the development of simple, sensitive and selective. For this the detection was based on the variation of the intrinsic fluorescence of proteins (by its specific interaction with the analytes) and the specific combination of extrinsic fluorophores. For the results presented in this plan can be affirmed that the protein fraction obtained can be used as a fluorescent probe in the determination of analytes of this study.Based on the five determinations of analyte, the values of LD and LQ are satisfactory for applying the method in environmental samples (ground) and clinical (urine). Measurements of Gal showed satisfactory performance to suit different types of samples (LD = 1.3 x 10-9mol L-1eLQ = 2.1 x 10-8mol L-1) values and LD LQ to atropine (9.7 x 10-10 mol L -1 and 2.4 x 10-8 mol L-1, respectively) appear to be suitable as other sensors, such as eletroquimioluminescentes showed a value of 1 LQ × 10-7 mol L-1 in urine samples. The method for pesticide methomyl (LD = 9.5 x 10-10 mol L-1 and LQ = 2.2 x 10-8mol L-1), methamidophos (LD = 1.5 x 10-9 mol L-1 and LQ = 3.8 x 10-8 mol L-1) and methyl parathion (LD = 9.7 x 10-10 mol L-1 and LQ = 1.8 x 10-7 mol L-1) comparing presents betterperformance to the other methods described in literature. The method proposed in soil samples and urine (no pretreatment) had recovered from 88% (ground pesticides) and five of analytes in urine. The t test comparison of means, applied to sets of determinations by fluorescence probe method and HPLC indicated the statistical equality in both recoveries. The adaptation of the proposed method a system of the biosensor with the use of an extrinsic probe (thioflavin T) has positively evaluated allowing immobilization of the protein in microplates and the use of thioflavin T as a fluorescent probe-connecting AChE inhibitors.