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Deriváty Amaryllidaceae alkaloidů jako látky potenciálně využitelné v terapii nádorových onemocnění / Derivatives of Amaryllidaceae alkaloids as potential drugs in the treatment of tumor diseasesValachová, Iva January 2020 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacognosy Candidate: Iva Valachová Supervisor: Pharm.Dr. Daniela Hulcová, Ph.D. Title of diploma thesis: Derivatives of Amaryllidaceae alkaloids as potential drugs in the treatment of tumor diseases Twelve aromatic derivatives were prepared. The substitutions were performed on the hydroxyl group at C-3. This was acylated with differently substituted benzoyl chlorides affording the corresponding esters. Structural identification was performed by 1D- and 2D- NMR, ESI-HRMS spectroscopic techniques and optical rotation measurement. The yield of all reactions was more than 60 %. After converting these derivatives to hydrochlorides, their biological activity was tested. The Amaryllidaceae alkaloid vittaine itself exhibits cytotoxic activity and therefore its derivatives have been investigated in this respect. It has been tested against 9 cancerous and 1 non-cancerous cell lines. 3-O-(4-Chloro-3-nitrobenzoyl)vittatine showed the highest cytotoxic activity, unfortunatelly, it does not selectively affect only cancerous cells. Conversely, 3-O-(2-naphthoyl)vittatine has a selective effect on the HT-29 cancerous cell line (colorectal carcinoma) with a viability value of 32 ± 3 %, potentially being the subject of further studies of cytotoxicity...
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Deriváty Amaryllidaceae alkaloidů a jejich biologická aktivita: Deriváty tazetinu II / Derivatives of Amaryllidaceae alkaloids and their biological activity: Derivatives of tazettine IIZelina, Dušan January 2020 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany Candidate: Dušan Zelina Supervisor: doc. Ing. Lucie Cahlíková, Ph.D. Title of diploma thesis: Derivates of Amaryllidaceae alkaloids and their biological activity: Derivates of tazettine II Plants of family Amaryllidaceae are a rich source of alkaloids that are characterized by a broad biological activity. Perhaps the world's best-known member of this family has become galanthamine, which, because of its potent inhibitory potential, has found a place in the treatment of Alzheimer's disease. Based on the conducted studies, the alkaloid tazettine has been chosen for this thesis. The main purpose was to prepare more active derivatives of tazettine and to test the biological activity for potential use in the treatment of cancer and Alzheimer's disease. Ten aromatic esters of tazettine were prepared. Reaction yields ranged from 33,5-69,3 %. Derivatives were identified by MS, NMR and optical rotation. Prepared compounds were tested for their inhibitory potential against human cholinesterases - AChE and BuChE. Unfortunately, it has not been possible to prepare derivatives, which exhibit significant activity in inhibiting AChE or BuChE. Anti-tumor activity of the derivates has been tested on the panel of selected...
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Deriváty Amaryllidaceae alkaloidů a jejich biologická aktivita: Deriváty tazettinu I / Derivatives of Amaryllidaceae alkaloids and their biological activity: Derivatives of tazettine IPidaný, Filip January 2020 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany Candidate: Filip Pidaný Supervisor: Assoc. Prof. Ing. Lucie Cahlíková, Ph.D. Title of diploma thesis: Derivatives of Amaryllidaceae alkaloids and their their biological activity: Derivatives of tazettine I A study conducted between 1981 and 2014 found that 65% of small molecule based drugs are related to natural substances. The plants of the family Amaryllidaceae contain a particular and still not fully investigated group of alkaloids called Amaryllidaceae alkaloids. Their important biological effects include, for example, antiviral, antibacterial, antifungal, antiparasitic, cytotoxic and, in particular, motor-neuronal system-mediated effects mediated by inhibition of cholinesterases. A widespread Amaryllidaceae alkaloid is tazettine, a structural type alkaloid of tazettine that has increased interest in the early 1970s due to its cytotoxic acitivity, but appears less interesting in the studies conducted. The subject of this thesis was the preparation of tazettin alkaloid derivatives. The cholinesterase inhibitory activity was then tested. Cytotoxic activity in a panel of selected tumor and healthy cell lines was studied by screening. Unfortunately, none of the derivatives prepared by us showed an...
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Alkaloidy rodu Narcissus: isolace, strukturní identifikace, biologická aktivita / Alkaloids of genus Narcissus: isolation, structural identification, biological activityŠimková, Hana January 2021 (has links)
Charles University, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany Author: Hana Šimková Supervisor: prof. Ing. Lucie Cahlíková, Ph.D. Title of diploma thesis: Alkaloids of genus Narcissus: isolation, structural identification, biological activity Key words: Narcissus, alkaloids, biological activity, Alzheimer's disease, cytotoxic activity The aim of the diploma thesis was an isolation of alkaloids with a focus on minor fractions. These fractions were obtained from the summary alkaloid extract of Narcissus pseudonarcissus cv. Carlton. The method of preparative TLC was used for the isolation of alkaloids. Three substances of alkaloid origin marked as Fj 3-4/kr, F 7/2-1, F 7/2-3 were isolated from the assigned fractions. These substances were identified as alkaloids of homolycorine type lycorenine, homolycorine and hippeastrine by using GC-MS, NMR and optical rotation. The results were also compared with data in the literature. These three alkaloids were tested for their inhibitory activity against AChE, BuChE, POP and GSK-3β. The inhibitory activity against AChE and BuChE was compared with the reference substances galanthamine (IC50 AChE = 1,71 ± 0,07 μM, IC50 BuChE = 42,3 ± 1,3 μM) and huperzine A (IC50 AChE = 0,033 ± 0,001 μM, IC50 BuChE> 1000 μM). The inhibitory...
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Intramolecular Ring Opening Reactions of Aziridines by π-NucleophilesPulipaka, Aravinda B. 22 April 2008 (has links)
No description available.
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Synthèse et désymétrisation d'arylcyclohexa-2,5-diènes : application à la synthèse totale de l'épi-ElwesineRousseau, Géraldine 13 November 2008 (has links)
La désymétrisation d’arylcyclohexa-2,5-diènes est une méthode très efficace pour obtenir en une seule étape des squelettes complexes à partir de synthons simples. Lors de cette thèse, une nouvelle approche à la synthèse d’arylcyclohexadiènes porteur d’un centre quaternaire a été développée. L’une des structures synthétisées par cette voie a ensuite été désymétrisée par une réaction d’hydroamination diastéréosélective, nous permettant de réaliser la première synthèse énantiosélective de l’épi-Elwesine. Notre démarche s’est ensuite orientée vers la synthèse et la désymétrisation de nouveaux types de diènes spirocycliques de type oxindoles. La présence dans ces diènes de deux faces très différenciées nous a permis de réaliser des processus complètement diastéréosélectifs. De plus une nouvelle séquence réarrangement-alkylation a été mise au point, nous permettant d’accéder efficacement à des squelettes de type phénanthridinones de façon régio- et diastéréosélective. / The desymmetrization of arylcyclohexa-2,5-dienes is a powerful method to synthesize complex structures from simple synthons in a single step. We first developed a new protocol to obtain arylcyclohexa-2,5-dienes bearing a quaternary center. One of these structures was desymmetrized via a diastereoselective hydroamination and further elaborated into epi-Elwesine, an Amaryllidaceae alkaloid. We next turned our attention towards the synthesis and desymmetrization of spirocyclic cyclohexadienes. Diastereoselective processes were carried out due to the presence of two well- differentiated faces. A new rearrangement-alkylation process was developed and provides efficient access to phenanthridinones regio- and diastereoselectively.
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Supercritical fluid extraction and analysis of indigenous medicinal plants for uterotonic activity.Sewram, Vikash. January 1997 (has links)
Ingestion of extracts prepared from various medicinal plants to induce or augment labour
is common amongst Black South African women during the late stages of pregnancy.
This applies particularly to the rural areas where modern health care facilities are often
lacking. Many of these plants have not been investigated scientifically and one needs to
substantiate claims of quality, safety and efficacy. Furthermore, it is believed that the
consumption of these plant extracts can result in foetal meconium staining at delivery.
An investigation into the uterotonic properties of three plants viz. Ekebergia capensis
Sparrm. Clivia miniata (Lindl.) Regel. and Grewia occidentalis L. were carried out using
guinea pig uterine smooth muscle in vitro. Supercritical fluid extraction was performed
with water modified supercritical carbon dioxide to extract the uterotonic components.
An attempt was also made to couple supercritical fluid extraction directly on-line to the
bioassay so that on line screening of crude plant extracts could be performed within short
periods of time. The effects of supercritical CO2 decompression on temperature and pH of
the muscle bathing solution were considered since these factors affect muscle
contractility. The direct effects of excess CO2 on intracellular mechanisms were
eliminated by constructing a CO2 reduction interface together with passage of carbogen
which aided in the rapid displacement of excess CO2, As samples of these extracts were
found to induce muscle contraction, supercritical fluid fractionation (SFF) was performed
by sequentially increasing the fluid density. Extracted fractions were obtained by
sequentially increasing the pressure at constant temperature and modifier concentration in
an attempt to identify the active fractions. Extractions were performed at 200 atm, 300
atm and 400 atm respectively. Subsequent testing of these fractions enabled the detection
of active and inactive fractions as well as a fraction that had a spasmolytic effect on
uterine muscle. The 400 atm extracts of E. capensis and C. miniata displayed maximum
activity while only the 300 atm extract of G. occidentalis induced uterine muscle
contraction. Subsequent analysis of the sequentially extracted fractions, by high
performance liquid chromatography and micellar electrokinetic capillary chromatography
revealed that certain compounds present in the fractions that stimulated muscle
contraction, were sensitive to the extraction pressure hence making it possible to
determine the compounds that were likely to be active. Column chromatography
followed by various spectroscopic techniques were performed in an attempt to isolate and
elucidate the structures of the compounds that were present in the plant extracts. The
extract of Ekebergia capensis yielded five known compounds (B-sitosterol, oleanonic
acid, 3-epioleanolic acid, 2,3,22,23-tetrahydroxy-2,6,1 0, 15,19 ,23-hexamethyl-6, 10, 14, 18-
tetracosatetrene and 7-hydroxy-6-methoxy coumarin. The extract of Clivia miniata
yieded linoleic acid and 5-hydroxymethyl-2-furancarboxaldehyde while the extract of
Grewia occidentalis yielded 3-(4-hydroxy-3-methoxyphenyl)-2-propenal, a novel
compound 2,2' ,6,6'-tetramethoxy-4'-al-4-(w-oxo-E-propenyl)-biphenyl and oleanonic
acid. The pure compounds were further evaluated pharmacologically to identify the
active components and assess the physiological mode of action by the use of various
receptor blockers. Oleanonic acid, 3-epioleanolic acid, linoleic acid and 5-
hydroxymethyl-2-furancarboxaldehyde and 3-(4-hydroxy-3-methoxyphenyl)-2-propenal
were found to induce an agonistic muscle response. All these compounds were observed
to mediate their effects through the cholinergic receptors. The results obtained in this
study supports the claim of these plants possessing uterotonic properties. / Thesis (Ph.D.)-University of Natal, Durban, 1997.
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Alkaloidy rostlin čeledi Amaryllidaceae jako potenciální léčiva v terapii civilizačních onemocnění / Alkaloids of the Amaryllidaceae family as potential drugs in therapy of diseases of affluenceBreiterová, Kateřina January 2019 (has links)
Charles University, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany Candidate: Mgr. Kateřina Breiterová Supervisor: Assoc. prof. Ing. Lucie Cahlíková PhD. Title of Doctoral Thesis: Alkaloids of the Amaryllidaceae family as potential drugs in therapy of diseases of affluence Key words: alkaloids, Amaryllidaceae, analogues, AChE, BuChE, POP, GSK-3β, cell cycle progression, apoptosis Narcissus cv. Professor Einstein was chosen based on results of previous screening studies for detailed phytochemical work for the purpose of isolation of the widest range of AmA. From 34,3 kg of fresh bulbs was obtained 31,7 g of purified alkaloidal extract, which was processed using column chromatography with stepwise elution by light petrol, chloroform and ethanol in different ratios to almost 500 fractions. These fractions were fused into 27 subfractions, which were processed by preparative TLC, vacuum column chromatography and crystallization. Finally, 25 pure alkaloids were isolated. All compounds were identified by GC-MS, ESI-MS, NMR, optical rotation and literature. One compound was identified as a new unpublished alkaloid of lycorine structure type. All alkaloids isolated in sufficient amount were tested for their biological activities associated with Alzheimer's disease (inhibition of...
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Caractérisation des propriétés anticancéreuses in vitro et in vivo de la narciclasine au sein de modèles expérimentaux de mélanomes murins et humains / Characterization of in vitro and in vivo anti-cancer properties of narciclasine in experimental models of murin and human melanomaVan Goietsenoven, Gwendoline 07 June 2012 (has links)
Le mauvais pronostic associé aux mélanomes est dû aux taux de réponses très faibles de ces cancers à la radiothérapie et à la chimiothérapie, cette résistance provenant essentiellement de la résistance des mélanomes aux stimuli pro-apoptotiques qui représentent la majorité de l’arsenal anticancéreux actuel.<p>Les plantes de la famille des Amaryllidaceae ont été utilisées dans la médecine traditionnelle à travers le monde notamment pour le traitement des tumeurs. Il s’est avéré que les composés responsables de l’activité anticancéreuse de ces traitements traditionnels étaient des alcaloïdes, dont les isocarbostyriles. Nous avons voulu caractériser les propriétés anticancéreuses de la narciclasine, un isocarbostyrile, in vitro et in vivo, et étudier son mécanisme d’action antitumoral dans des cellules de mélanome.<p>Nous avons tout d’abord analysé l’activité inhibitrice de croissance in vitro de ces composés et nous avons observé que l’activité de ces produits était indépendante du caractère résistant ou non des lignées cancéreuses aux stimuli pro-apoptotiques. De plus, à l’exception de la pseudolycorine, ces composés ont une activité cytostatique au niveau de la croissance des cellules cancéreuses. <p>Nous avons ensuite identifié le facteur d’élongation eEF1A, une GTPase, comme étant une cible potentielle de la narciclasine. De nombreux effets biologiques exercés par la narciclasine (inhibition de la synthèse protéique, désorganisation du cytosquelette d’actine, etc…) peuvent s’expliquer grâce à cette cible. Des travaux antérieurs à ma thèse mais auxquels j’ai participé, suggéraient déjà l’implication d’autres GTPases appartenant à la famille des Rho GTPases comme pouvant être également des cibles de la narciclasine. Nous avons également identifié au cours de notre travail de thèse d’autres GTPases, telle que Rac1, comme étant des cibles de la narciclasine. Nous avons toutefois observé que certaines GTPases telles que Ran ne semblaient pas être des cibles de la narciclasine lorsque celle-ci exerce ses effets antitumoraux. Ainsi, si de nombreuses GTPases semblent être des cibles privilégiées de l’action antitumorale de la narciclasine, toutes les GTPases ne le sont pas. Nous avons observé en fait que la narciclasine n’entre pas en compétition avec le GDP / GTP au sein de la poche GTP du facteur d’élongation eEF1A. <p>Des études d’activité in vivo réalisées par notre groupe, soit antérieures à mon travail de thèse (gliomes, cancer du poumon NSCLC), soit au cours de ma thèse (mélanomes), ont montré que la narciclasine à des doses non toxiques (administrations chroniques de 1 mg/kg par voie orale ou par voie intraveineuse) apporte un bénéfice thérapeutique dans différents types de modèles de cancers (gliomes, mélanomes, cancers NSCLC) à conditions que les cellules tumorales soient greffées de manière orthotopique au sein du cerveau de souris immunodéficientes. Ces mêmes cancers s’avèrent insensibles à ces doses non toxiques de narciclasine lorsque les cellules sont greffées en dehors du cerveau chez la souris immunodéficiente. <p>L’ensemble de nos résultats suggèrent que la narciclasine pourrait devenir un nouvel outil dans le combat contre les cancers cérébraux primaires et secondaires, les métastases cérébrales constituants un problème d’importance pour des cancers tels que les mélanomes, les cancers du poumon, les cancers du sein, les cancers rénaux et les cancers colorectaux. Les cancers primaires du cerveau représentent environ 5% de l’ensemble des cancers solides de l’adulte et jusqu’à 20-30% chez l’enfant. Les métastases cérébrales, dont principalement les métastases cérébrales de mélanomes, représentent également environ 5% de l’ensemble des cancers solides de l’adulte. / Doctorat en Sciences biomédicales et pharmaceutiques / info:eu-repo/semantics/nonPublished
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Alkaloidy Narcissus 'Dutch 'Master' (Amaryllidaceae) a jejich biologická aktivita. II. / Alkaloids of Narcissus'Dutch Master ' (Amaryllidaceae) and their biological activity. II.Dvořáková, Zdeňka January 2016 (has links)
Dvořáková Zdeňka: Alkaloids of Narcissus 'Dutch Master' (Amaryllidaceae) and their biological activity II. Diploma thesis 2016, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology. The content of this work was isolation of compounds from the selected fraction ND-6 obtained by column chromatography of Narcissus 'Dutch Master' alkaloid extract. Preparation of extract and its column chromatography was performed by Mrg. Daniela Hulcová as part of her doctoral studies. By the means preparative TLC was from fraction ND- 6 homolycorine type alkaloid (+)-O-methyllycorenine gained. Its structure was determined on the basis NMR, GC-MS analysis and optical rotation. The obtained data were compared with facts in known literature. By the isolated alkaloid was determined its cholinesterase inhibitory activity against acetylcholinesterase and butyrylcholinesterase. Its inhibitory activity was expressed as IC50 (M) and compared with known standards galanthamine, physostigmine, and Huperzine A. This alkaloid is inactive against cholinesterase (IC50 AChE > 1000 M, IC50 BChE > 1000 M). On the basis of gained results, we can evaluate this alkaloid from the point of view of cholinesterase inhibition as potentially unusable in the treatment of AD. Key...
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