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Baugaard, Carlo. "The synthesis and electrochemical studies of chalcones and flavanones: an investigation of their antioxidant activity." Thesis, University of Western Cape, 2013. http://hdl.handle.net/11394/3312.
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>Magister Scientiae - MScFlavonoids, one of the biggest classes of secondary metabolites, are found abundantly in nature in a broad range of fruits, vegetables and beverages such as tea, coffee, beer, wine and fruit drinks. Flavonoids have been reported to exert multiple biological functions as well as tremendous pharmacological activity, including anticancer activity, protection, antioxidant activity, cardiovascular protection, antibacterial, antifungal and antiviral activity. The antioxidant activity of flavones is reported to be associated with those bearing hydroxyl functions. In the present study, several reaction steps have been carried out to synthesize three sub classes of flavonoids namely; chalcones, dihydrochalcones and flavanones with various substituents attached. The first step involved protection of hydroxyl groups of acetophenone and benaldehyde as starting materials. Thereafter the Clasien Schmidt condensation reaction, under basic conditions, was performed to afford chalcone intermediates. Treatment of these chalcones with sodium acetate, under reflux, afforded flavanones as a single product in high yields. Thereafter all protecting groups where removed to yield the final products. All products and intermediates where purified by column chromatography and were characterized by Nuclear Magnetic Resonance Spectroscopy (NMR) (1H NMR and 13C NMR). An electrochemical analysis on all flavonoid compounds was performed by Cyclic Voltammetry (CV) and Square Wave Voltammetry (SWV) to give information on the accessible redox couples identified by their oxidation potentials. Oxidation potentials, which gave valuable information about reducing ability and hence the antioxidant activity, where used to compare all compounds. The antioxidant activity was observed to increase with the addition of hydroxyl groups on the B-ring. Compounds with a combination of hydroxyl groups on the A-ring and methoxy groups on the B-ring showed increased antioxidant activity when compared to those with only hydroxyl groups on the base structure. 2, 5, 4’-trihydroxy dihydrochalcone showed moderate antioxidant ability. However the 2, 5, 4’-trihydroxychalcone, containing the α, β unsaturated double bond, proved to have the greatest antioxidant ability.
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Armitage, Edward Simon Marco. "Design and synthesis of Combretastatin A-4 like chalcones and their analogues, and other anticancer agents." Thesis, Cardiff University, 2007. http://orca.cf.ac.uk/56191/.
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This thesis covers work investigating the design, synthesis and evaluation of Combretastatin A-4 like chalcones and their analogues, and other anticancer agents. The first two chapters are an introduction to cancer chemotherapy and the development of tubulin as a target for chemotherapy. Chapter one includes information on cancer epidemiology, the history of cancer and the development of important cancer chemotherapy agents. While the second chapter describes the role of tubulin in mitosis, and the development of anticancer agents that target tubulin. The third chapter describes the background to the chalcone project, as well as the design and synthesis of new Combretastatin A-4 like chalcones and their analogues. To further the investigation of the substitution of the a-hydrogen of the chalcone with various groups, a series of a-arylchalcones was synthesized. The substitution of a-hydrogen with various aryl groups generally shows a significant increase in the anticancer activity of the chalcone. The effect of the conformation of the chalcone on its anticancer activity was also investigated by synthesizing two series of chalcone analogues which mimic the s-trans arrangement of chalcone, the indanones and indenones. Several of the indanones and indenones showed high levels of cytotoxicity with the CA-4 like indenone having an IC5o(K562) value of 0.019 uM. Chapter four looks at other chalcones with anticancer activity including the naturally occurring chalcone 4-hydroxyderricin, which has been isolated from the roots of Angelica keiskei and has shown to have anti-tumour promoting properties. As part of my PhD study the natural product 4-hydroxyderricin and a series of analogues was synthesized to investigate its anticancer activity. In chapter five I synthesized the anticancer agent KNK437 which has been shown to be a dose dependant inhibitor of the acquisition of thermotolerance in several different tumours. The study found that KNK437 sensitizes human leukaemia cells to the 17-allylamino-demethoxy geldanamycin induced apoptosis.
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Anjos, Murilo Machado dos. "Síntese, otimização e avaliação da atividade biológica de derivados de chalconas." Universidade Federal de Goiás, 2015. http://repositorio.bc.ufg.br/tede/handle/tede/5610.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
The world's population sees aging and some diseases that become more common. Alzheimer's disease (AD) is a dementia caused by loss of cognitive function of the individual and drugs used in their treatment is based on the inhibition of the enzyme acetylcholinesterase (AChE). Cancer is a group of diseases that develop due to the disorderly proliferation of cells may be related to genetic factors as well as dietary habits and exposure to radiation, the treatment being based on three main techniques: surgery, radiation and chemotherapy. In this work we synthesized 15 compounds (11 chalcones and 4 imines), based on the condensation of Claisen-Smth, and they are characterized by NMR (1H and 13C), IV These compounds were submitted to acetylcholinesterase activity by the modified method of Elman, using CCD and Martson, in addition to the evaluation of cytotoxic tumorias lines SF-295 (glioblastoma - human), HL-60 (acute leukemia promielítica) and HCT-116 (colon). The compounds showed no activity for the enzyme AChE front of the methods employed, and this cause investigated using molecular modeling methods, which sought in the literature active compounds for this enzyme, containing resemblance with the structures synthesized in this work. 80 descriptors were calculated being submitted to statistical analysis (Fisher's weight) where the number of variables is reduced to 24 and these have been selected GAP and bond angle where it was observed that the values of the synthesized compounds, mostly It was found out of range for the active compounds. The previous modeling studies are not sufficient to determine the causes of inactivity of the compounds, being necessary to the realization of a structure and reactivity studies. The evaluation of the antitumor compounds presented become more positive as the MCH-1
A população mundial veem envelhecendo e com isto algumas doenças tornam-se mais comum. A doença de Alzheimer (DA) é uma demencia causada pela perda da função cognitiva do indivíduo e as drogas empregadas no seu tratamento tem como base a inibição da enzima acetilcolinesteráse (AChE). O cancer é um conjunto de doenças que se desenvolvem pela multiplicação desordenada de células, pode estar relacionado com fatores genéticos como também hábitos alimentares e exposição à radiação, sendo o tratamento baseado em três principais técnicas: cirurgia, radioterapia e quimioterapia. Neste trabalho foram sintetizados 15 compostos (11 chalconas e 4 iminas), baseando-se na condensação de Claisen-Smth, sendo os mesmos caracterizados por RMN (1H e 13C) e I.V. Estes compostos foram submetidos à atividade anticolinesterásica pelo método modificado de Elman, utilizando-se CCD, e Martson, além da avaliação citotóxica para as linhagens tumorias SF-295 (glioblastoma - humano), HL-60 (leucemia promielítica aguda) e HCT-116 (colón). Os compostos não apresentaram atividade para a enzima AChE frente aos métodos empregado, sendo esta causa investigada utilizando métodos de modelagem molecular, onde buscou-se na literatura compostos ativos para esta enzima, que continham similiaridades com as estruturas sintetizadas neste trabalho. Foram calculados 80 descritores sendo estes submetidos à uma análise estátistica (peso de fisher) onde o número de variáveis foi reduzido para 24 e destas foram selecionadas o GAP e ângulo de ligação, onde observou-se que os valores dos compostos sintetizados, em sua maioria, estavam fora da faixa encontrada para os compostos ativos. Os estudos prévios de modelagem não são suficientes para determinar as causas da inatividade dos compostos, sendo necessário a realização de um estudo de estrutura e reatividade. A avaliação antitumoral dos compostos apresentou-se mais positiva, sendo as chalconas Mch-1 e Mch-7 ativas para duas linhagens celulares tumorais (HCT-116 e SF-265).
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Rivera, Sylvie. "Synthèse et réactivité des chalcones." Paris 5, 1997. http://www.theses.fr/1997PA05P150.
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Schicker, Susanna Heidi. "Synthesis of intermediates for chalcone and 6-MSA biosynthesis." Thesis, University of Bristol, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336910.
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Zakai, Uzma I. "Design, Synthesis, and Evaluation of Chalcogen Interactions." Diss., The University of Arizona, 2007. http://hdl.handle.net/10150/195272.
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Contributions in the area of cationic chalcogen-chalcogen and chalcogen-π interactions as well as chalcogen mediated Group 14-iron interactions have been made. This work reports the electrochemical oxidation of 8- and 10-membered ring dichalcogenides appended with β-silicon and tin substituents. The heterocycles with tellurium undergo reversible oxidation but those with sulfur or selenium are irreversibly oxidized. The ionization energies of these mesocyclic chalcogenoethers were determined by photoelectron spectroscopy. These lowest ionization energies reflect substantial (0.53-0.75 eV) orbital destabilizations due to the neighboring C-Si or C-Sn bonds. In particular, a novel Si-Si effect on the ionization of these β-disilyl sulfides and selenides was found by PES measurements. Fe₂S₂(CO)₆ clusters with a C-Sn or C-Sn-C moiety bridging the sulfur atoms or a CH₂SnMe₃ group attached to each sulfur have also been studied by photoelectron spectroscopy. Stannylation lowers the ionization energy of sulfur lone pair orbitals in these systems owing to a geometry dependent interaction as well as the Fe-Fe HOMO. Additionally, various sulfur and phosphine substituted hydroquinone and catechol redox ligands have been synthesized to append to iron sulfur clusters. Lastly, model m-terphenyl methyl and phenyl chalcogenoethers that will be further used to study cationic aromatic-chalcogen interactions have been synthesized in either of two ways. Suzuki couplings of 2,6-dibromoaniline and (2,6-diiodo-4-methylphenyl)(methyl)sulfane afford m-terphenyl methyl thioethers in 27-42% yield. Deprotonation of 1,3-dichlorobenzene and treatment with substituted aryl Grignard reagents generated m-terphenyl anions which were quenched with alkyl or aryl dichalcogenides to give m-terphenyl chalcogenoethers in 16-74% yields. A new synthesis of phenyl m-terphenyl chalcogenoethers was found. Treatment of substituted iodo-m-terphenyls with diphenyl dichalcogenides using CsOH⋅H₂O in DMSO affords phenyl m-terphenyl chalcogenoethers in 19-84% yields. Extending the scope of this methodology to other 2,6-blocked aryl halides as well as the use of aliphatic and aromatic thiols or secondary alicyclic amines has been initially explored. Finally, o-methoxy substituted m-terphenyl chalcogenoethers show atropisomerism, with barriers in the range of 66-80 kJ/mol, as determined by variable temperature ¹H NMR spectroscopic studies.
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Malmström, Jonas. "Synthesis, properties and applications of chalcogen-containing antioxidants." Doctoral thesis, Uppsala University, Department of Chemistry, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-1085.
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In the first part, the preparation and properties of chalcogen-containing vitamin E analogues are described. The sulfur compound 3,3,4,6,7-pentamethyl-2,3-dihydrobenzo[b]thiophene-5-ol was prepared by two different routes using ionic and radical chemistry. Interesting rearrangements were observed in the two synthetic pathways.
A new methodology for the synthesis of dihydroselenophene and dihydrotellurophene derivatives is described. In the preparation of the vitamin E analogues 2,3-dihydrobenzo[b]selenophene-5-ol and 2,3-dihydrobenzo[b]tellurophene-5-ol a tellurium-mediated tandem SRN1/SHi sequence was suggested to be operative. 2,3-Dihydrobenzo[b]thiophene-5-ol and the vitamin E-like selenide 2-methyl-2-(4,8,12-trimethyl-tridecyl)-selenochroman-6-ol were prepared via intramolecular homolytic substitution at sulfur and selenium, respectively. The first rate constant for intramolecular homolytic substitution at tellurium is also reported (5x108 s-1 at 25 °C).
The antioxidant profile for 2,3-dihydrobenzo[b]furan-5-ol and its 1-thio, 1-seleno, and 1-telluro analogues is described. By means of pulse radiolysis, it was shown that the one-electron reduction potentials (ArO·/ArO-) were independent of the chalcogen (0.49-0.52 V vs NHE). The O-H bond dissociation enthalpies for the compounds were also estimated to be similar (336-340 kJ mol-1). The pKa values and the oxidation potentials were also determined for these compounds. For some compounds the rate of hydrogen atom donation to tert-butoxyl radicals was determined by means of laser flash photolysis. Using a two-phase lipid peroxidation model, it was demonstrated that the selenium and tellurium analogues could be regenerated in the presence of a stoichiometric amount of a reducing agent. The organotellurium analogue also acted as a good glutathione-peroxidase mimic and as a potent inhibitor of lipid peroxidation in liver microsomes.
In the second part of the thesis the stabilizing capacity of bis[4-(dimethylamino)phenyl]telluride was investigated in the thermoplastic elastomer PACREL®. It was demonstrated that the addition of 0.17-0.50 % of the telluride significantly improved the tensile strength and elongation at break of the polymer. Chemiluminescence measurements showed that the organotellurium compound prolonged the induction period of thermo-oxidation and reduced the total luminescence intensity of the material.
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Evangelista, Fernanda Cristina Gontijo. "Evaluation of in vitro antitumor activity of triazole / azide synthetic chalcones." Instituto Nacional de Pesquisas da Amazônia, 2018. http://bdtd.inpa.gov.br/handle/tede/2639.
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Fundação de Amparo à Pesquisa do Estado de São Paulo - FAPESP
Many compounds isolated from lichens exhibit biological activity, and a number of them are proven sources of antitumor drugs. Even simple structural changes to these bioactive compounds can lead to potentiation of their activity. The purposes of this study were to evaluate the antiproliferative activity and selectivity of the following compounds isolated from lichens: atranorin; diffractaic, divaricatic, perlatolic, psoromic, norstitic, protocetraric, and fumarprotocetraric acids; and alkyl derivatives. Cytotoxicity tests based on the sulforhodamine B dye were performed on seven lines of neoplastic cells and one line of normal cells (3T3)
Muitas substâncias isoladas de liquens apresentam atividades biológicas, e algumas demonstraram ser fontes promissoras de drogas antitumorais. Modificações estruturais simples a partir dessas substâncias bioativas podem levar a potencialização da atividade apresentada. Os objetivos deste estudo foram avaliar a atividade antiproliferativa e seletividade dos seguintes compostos isolados de liquens: atranorina, ácidos difractaico, divaricático, perlatólico, psorômico, norstítico, protocetrárico e fumarprotocetrárico e derivados alquílicos. O ensaio de citotoxicidade foi realizado com corante sulforrodamina B em sete linhagens de células neoplásicas e uma linhagem de células normais (3T3)
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鄭重展 and Chung-chin Cheng. "Syntheses and photophysics of luminescent polynuclear coinage metal complexes with chalcogen and pnictogen: containing bridging ligands." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31241530.
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Khan, Jamal Rafique. "Synthesis of heterocycles containing chalcogens by C-H functionalization." reponame:Repositório Institucional da UFSC, 2014. https://repositorio.ufsc.br/xmlui/handle/123456789/131002.
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Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Físicas e Matemáticas, Programa de Pós-Graduação em Química, Florianópolis, 2014.Made available in DSpace on 2015-03-18T21:07:51Z (GMT). No. of bitstreams: 1 332770.pdf: 14134351 bytes, checksum: cc0da4f1aceec596f78e10884c146b30 (MD5) Previous issue date: 2014
No presente trabalho desenvolveram-se novas metodologias eficientes, econômicas e ambientalmente adequadas para a síntese de oxadiazóis e benzotiazóis contendo uma porção organocalcogênio. Primeiramente, desenvolvemos a síntese de oxadiazóis selenados e tiolados através da funcionalização de ligação Csp2-H promovida por K2CO3, em um meio reacional livre de metais de transição. Em uma primeira etapa foram preparados oxadiazóis selenados com potencial para aplicações biológicas. Sob condições suaves, a reação ocorreu de maneira eficiente na presença de um equivalente do correspondente oxadiazol I, um equivalente de base (K2CO3), 0,5 equivalentes do correspondente dicalcogeneto de organoíla II, na presença de ar atmosférico. Através dessa metodologia, uma série de oxadiazóis calcogenados III na posição 5 do heterociclo foram obtidos em rendimentos que variaram de bons a excelentes. Adicionalmente, explorou-se a reatividade dos oxadiazóis selenados 3 em reações de troca calcogênio-lítio. Os intermediários oxadiazóis litiado assim obtidos foram capturados, in situ, com diferentes eletrófilos. É importante salientar, também que essa reação ocorreu de forma eficiente quando se aumentou sua escala para 10 mmol.Em uma segunda etapa desenvolvemos um novo método para a incorporação de calcogênios em benzotiazóis via reação de calcogenação direta da ligação C-H. Realizou-se a síntese de 2-organocalcogeno-1,3- benzotiazóis V através da calcogenação direta entre 1,3-benzotiazóis IV e dicalcogenetos de organoíla II catalizada por Fe3O4 nanopartículado. Esta metodologia permitiu a obtenção dos respectivos produtos calcogenolados V, em rendimentos que variaram de moderados a excelentes. Realizou-se, também, com sucesso, a reciclagem do catalisador em 4 ciclos sem um decréscimo acentuado no rendimento.
Abstract : In the present work, we developed efficient, economical and greener procedures for to the synthesis of chalcogenated oxadiazoles and benzothiazoles. In the first part, we developed a K2CO3-promoted procedure for the synthesis of selenated and thiolated oxadiazoles 3 through Csp2-H bond functionalization, under transition metal-free conditions. We prepared for the first time selenated oxadiazoles, compounds with potential for biological applications. Under mild conditions, the reaction worked well in the presence of 1equiv. of oxadiazole I, a half equiv. of diorganyl dichalcogenides II, 1 equiv. of base (K2CO3), without the exclusion of air and moisture, affording a wide range of chalcogenated oxadiazoles III at the C5 position in good to excellent yields. The various substituents with different electronic effects and steric effects tolerated the optimized reaction conditions. Furthermore, selenated oxadiazole was explored for selenium-lithium exchange reaction and lithium-intermediate was trapped by different electrophiles. We were also successful in scaling up the reaction in up to 10 mmol. Subsequently, we developed a new method of incorporation of organoyl chalcogenides in benzothiazoles via direct chalcogenation of C-H bond. In this work, we report the synthesis of 2-organochalcogeno-1,3-benzothiazoles V via direct chalcogenation reactions between 1,3-benzothiazoles IV and diorganyl dichalcogenides II catalyzed by Fe3O4 nano particle. This methodology allowed us to obtain 2-chalcogen-1,3-benzothiazoles in moderate to excellent yields, as well as recycling successful the catalyst in up to 4 cycles without any major decrease in the yield.
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Zulu, Ayanda Ignatia. "Synthesis and evaluation of arylpyrrole-chalcone hybrids as antiplasmodial and antitrypanosomal agents." Thesis, Rhodes University, 2017. http://hdl.handle.net/10962/65268.
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林智豪 and Chi-ho Aaron Lam. "Syntheses, characterization and photophysics of polynuclear copper (I)and silver (I) complexes containing monoynyl, diynyl and chalcogen-type ligands." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31240434.
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Lewtas, M. R. "Synthesis and characterisation of palladium and platinum complexes of chalcogen-containing ligands." Thesis, Swansea University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.637897.
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The thesis contains reviews of the chemistry of transition metal polychalcogenides, the characterisation, properties and uses of transition metal dithiolenes and the synthetic history, characterisation and properties of transition metal diselenolenes. There are also reviews of the synthesis, characterisation and properties of dimers and trimers of the nickel triad containing phosphine ligands and two bridging chalcogenide atoms, the synthesis and characterisation of nickel triad polychalcogenides and transition metal ditelluorlenes. Other literature described concerns phosphine substituted dithiolene and diselenolene complexes of the nickel triad and the synthesis of transition metal diselenolenes from 1, 2, 3-selenadiazoles. The reactions of bis[bis(diphenylphosphino)ethane]palladium and -platinum with elemental chalcogens are described. Reaction of bis[bis(diphenylphosphino)ethane]platinum with elemental selenium in toluene under reflux, or of [bis(diphenylphosphino)ethane]dichloroplatinum with lithium polyselenide in tetradhydrofuran, led in good yield to the complex [bis(diphenylphosphino)ethane]-(tetraselenido-Se, Se)platinum whose structure was determined by X-ray crystallography. Reaction of bis[bis(diphenylphosphino)ethane]platinum with elemental tellurium, followed by treatment with dichloromethane led to isolation of the salt tris[bis(diphenylphosphino)ethane]di-μ3-telluridotriplatinum dichloride. Bis[bis(diphenylphosphino)ethane]palladium reacted with elemental selenium to give bis[bis(diphenylphosphino)ethane]di-μ2-selenidodipalladium or tris[bis(diphenylphosphino)ethane]di-μ3-selenidotripalladium dichloride depending on the conditions. The reactivity of palladium and platinum chalcogenide complexes containing dppe towards various activated alkynes was examined. The tetrachalcogenides [bis(diphenylphosphino)ethane](tetrasulphido-S, S)palladium, -platinum and [bis(diphenylphosphino)ethane](tetraselenido-Se, Se)platinum reacted with the activated alkynes dimethyl- and diethylacetylenedicarboxylate to form dithiolenes and diselenolenes such as [bis(diphenylphosphino)ethane]bis(ethoxycarbonyl)ethene-1,2-(diselenolato-Se, Se)]platinum.
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Kawamata, Yu. "Development of Chalcogen-Centred Chiral Catalysts and Their Applications to Asymmetric Synthesis." 京都大学 (Kyoto University), 2016. http://hdl.handle.net/2433/215328.
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Sugamata, Koh. "Studies on the Synthesis and Properties of Low-coordinated Chalcogen(II) Cations." 京都大学 (Kyoto University), 2012. http://hdl.handle.net/2433/157808.
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Matak, Andrija. "Synthesis and spectroscopic analysis of 4'-amino and 4'-sulfonamide chalcone derivatives and ultrastructural effects of 4'-sulfonamide boronic acid chalcone on Eimeria papillata sporozoites in vitro /." Link to Theses, 2008. http://eprint.cc.andrews.edu/38/.
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Rodrigues, Camila Coelho. "Estudo da apocinina, diapocinina e derivados: síntese, modelagem molecular, avaliação da atividade aceptora de radicais e neuroprotetora frente a sintomas da doença de Parkinson." Universidade Federal do Pampa, 2018. http://dspace.unipampa.edu.br:8080/jspui/handle/riu/3362.
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A apocinina apresenta estrutura pequena e possui diversas atividades biológicas, sua estrutura pode ser oxidada em certas condições e resultar na formação do seu dímero, a diapocinina. Como um potencial agente terapêutico, análogos estruturais da diapocinina, contendo grupos substituintes ligados a esta molécula, podem apresentar atividade neuroprotetora e aceptora de radicais. As chalconas apresentam estrutura química 1,3-diaril-2-propen-1-ona simples que permite variadas modificações estruturais com a finalidade de otimizar o perfil farmacológico ou direcioná-las para diferentes atividades biológicas. A resposta de maior destaque é a capacidade aceptora de radicais e atividade neuroprotetora. Neste trabalho foram realizadas a síntese e caracterização da diapocinina e seus derivados, a avaliação das propriedades físico-químicas e da atividade aceptora de radicais, estudos de modelagem e docking molecular, toxicidade in silico e in vivo, com a finalidade de se obter compostos que possam ser empregados como candidatos a novos fármacos aceptores de radicais e antiparkinsonianos. A diapocinina foi sintetizada a partir da apocinina e caracterizada por CLAE, espectroscopia IV, e RMN 1H e 13C. As chalconas derivadas da diapocinina com substituintes 4-Cl, 4-N(CH3)2, 4-OCH3 e 4-NO2, foram sintetizadas através da condensação de Claisen-Schmidt. A análise de capacidade aceptora de radicais foi realizada através do ensaio de DPPH utilizando como padrão BHT. A análise de toxidade in silico, especificamente o risco de causar genotoxidade, mutagenicidade, efeitos irritante e sobre sistema reprodutor, foi realizado através dos programas computacionais Osiris Property Explorer e admetSAR. Os estudos de docking molecular foram realizados utilizando o software iGemdock 2.1 e envolveu a avaliação de ligação individual da apocinina e diapocinina. Os protocolos experimentais pré-clínicos in vivo de avaliação de atividade frente a sintomas de doença de Parkinson foi realizado com Drosophila melanogaster. A apocinina demonstrou capacidade de captura de DPPH maior que seu dímero, sugerindo-se que este composto se apresenta como melhor candidato para o desenvolvimento de compostos com atividade antioxidante potencial. A partir da análise da toxicidade in silico observou-se que somente os compostos 4-N(CH3)2 e 4-NO2 apresentaram riscos de causar os efeitos mutagênicos e genotóxicos, sendo que os demais compostos apresentaram risco teórico baixo. Os resultados obtidos no estudo de docking molecular permitiram a obtenção de modelos teóricos onde a apocinina e a diapocinina não possuem ligação no mesmo sitio de interação. Assim sugere-se que estruturas químicas possam, de maneira simultânea, atuar no mesmo alvo, mas em sítios adjacentes de interação. A avaliação da atividade frente a sintomas da doença de Parkinson realizada através de ensaio de sobrevivência, toxicidade e comportamento com Drosophila melanogaster constata que tanto a apocinina e diapocinina são compostos promissores para o estudo e o desenvolvimento de agentes para se utilizar na terapêutica, com atividade neuroprotetora.
Apocynin is phenolic compound with a small structure which exhibit diverse pharmacological activities. Aromatic ring structure can be oxidized under enzymatic or in oxidizing medium generating its dimer, diapocinin. Structural analogues of diapocinin are considering a potential therapeutic agent, and depending on substituent moieties attached to this molecule. Chalcones have a simple chemical 1,3-diaryl-2-propen-1-one structure which allows structural modifications aiming the optimization of the broad recognized pharmacological profile or to reach some different biological activities. Oxygen radical acceptor (antioxidant) and neuroprotective are highlighted biological activities observed to these class of compounds and they were studied in this research. In this work, the synthesis and characterization of diapocinin and its chalcone derivatives, the evaluation of physicochemical properties and radical acceptor activity, molecular modeling and docking studies, in silico and in vivo toxicity, and evaluation of Parkinson’s disease in Drosophila melanogaster protocols were performed in order to support the new antioxidant and antiparkinsonian drugs. Diapocinin was synthesized from apocynin and characterized by HPLC, IR spectroscopy, and 1H and 13C NMR. Chalcones derived from diapocinin, with 4-Cl, 4-N(CH3)2, 4-OCH3 and 4-NO2, were synthesized by the condensation of Claisen-Schmidt. Radical acceptor evaluation was performed usign DPPH assay using BHT as standard. In silico toxicity analysis, specifically the risk of causing genotoxicity, mutagenicity, irritant effects and activity on the reproductive system, were performed using Osiris Property Explorer and admetSAR. Molecular docking studies were performed using iGemdock 2.1 software, and this study involved the evaluation of individual binding of apocynin and diapocinin and alfa-synuclein and NADPH oxidase. In vivo preclinical experimental protocols of activity against Parkinson's disease symptoms were performed with Drosophila melanogaster. Apocynin demonstrated higher DPPH radical capture than diapocynin, suggesting that this compound is the best candidate for the development of compounds with potential antioxidant activity. From the analysis of in silico toxicity, it was observed the 4-N(CH3)2 and 4-NO2 compounds presented risks of causing the mutagenic and genotoxic effects, and the other compounds presented low theoretical risk. The results obtained in the molecular docking study allowed the generation of theoretical models which the apocynin and diapocinin not show binding or interactions in the same molecular protein site. Thus, it is suggested that chemical structures may, simultaneously, act on the same target, but in adjacent sites of interaction. The evaluation of activity against Parkinson's disease symptoms performed by survival, toxicity and behavior assays with Drosophila melanogaster suggest the both apocynin and diapocinin are promising compounds for the study and development of agents to be used in therapy, with neuroprotective activity.
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Wiseman, Matthew Robert. "Synthetic studies of silver and gold complexes containing chalcogen donor ligands." Thesis, University of Bath, 2001. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341673.
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Poller, Maximilian J. [Verfasser], and Konstantin [Akademischer Betreuer] Karaghiosoff. "Synthesis and investigation of new phosphorus-chalcogen cations / Maximilian J. Poller ; Betreuer: Konstantin Karaghiosoff." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2019. http://d-nb.info/118539379X/34.
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Thevenin, Marion. "Développement de nouveaux agents antiparasitaires : vers la synthèse totale de la cissampeloflavone et de dérivés." Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-00871981.
Full textAbstract:
Les maladies tropicales provoquées par des parasites protozoaires tels que Trypanosoma brucei, Plasmodium falciparum et Leishmania donovani, infectent des milliards d'individus dans le monde et en tuent des millions chaque année. Actuellement, les phénomènes de résistance face aux thérapies actuelles utilisées pour traiter ces maladies dites " négligées " deviennent inquiétants et problématiques. Par conséquent, la découverte de nouvelles classes de molécules bioactives antiparasitaires est primordiale.C'est dans ce contexte que s'inscrit ce travail de thèse. La cissampeloflavone est un dimère chalcone-flavone isolé en 2003 d'une plante vénézuélienne, Cissampelos pareira. Cette molécule a démontré une bonne activité contre T. brucei (CI50 = 1 µM). Par ailleurs, des études de modélisation moléculaire ont prédit que son dérivé 4-désoxycissampeloflavone possèderait une bonne affinité pour une enzyme essentielle à la survie du parasite. Pour ces raisons, nous avons entrepris la synthèse totale de ces deux molécules originales jamais réalisée à ce jour.Des analogues simplifiés ont d'abord été synthétisés afin de mettre au point le schéma réactionnel pour former la cissampeloflavone et la 4-désoxycissampeloflavone. Ces composés ont pour base commune le noyau benzofurane qui porte soit la " partie chalcone " soit la " partie flavone " de ces dimères. Les deux synthèses totales ont ensuite été entreprises.Ce travail de thèse a notamment permis la création d'une librairie d'analogues benzofuranes polysubstitués, la découverte d'une réaction de méthylénation originale et la formation de nouveaux dérivés furanoflavones. La plupart ont été évalués sur T. brucei, P. falciparum et L. donovani. Plusieurs d'entre eux ont présenté une activité trypanocide intéressante et prometteuse.
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Robinson, Sarel Johannes. "Syntheses of chalcones and 2-aminopyrimidines and their evaluation as monoamine oxidase inhibitors and as adenosine receptor antagonists / Sarel Johannes Robinson." Thesis, North-West University, 2013. http://hdl.handle.net/10394/9534.
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Background and rationale -
Parkinson’s disease is a neurodegenerative disorder characterised by reduced levels of
dopamine in the brain. The cause of Parkinson's disease is still unknown; however several
theories pertaining to the etiology exist. Current treatment mainly aims at dopamine
replacement, with agents such as levodopa and dopamine agonists that provide patients
with symptomatic relief. This relief is unfortunately only temporary as the progression of the
disease is not halted. Furthermore, these therapies are associated with a range of side
effects and novel approaches to the treatment are thus urgently required. Adenosine A2A
receptor antagonists recently emerged as a promising non-dopaminergic alternative, not
only as symptomatic treatment, but also as potential neuroprotective therapy.
Adenosine A2A receptors are co-localised with dopamine D2 receptors in the striatum and
other nuclei of the basal ganglia. Adenosine A2A stimulation decreases the affinity of
dopamine for the D2 receptor, and increase cyclic AMP (cAMP) levels. The stimulation of
dopamine D2 receptors, in contrast, decreases cAMP levels and therefore these receptors
(A2A and D2), act in an opposing manner. Adenosine A2A antagonism will thus have similar
effects as dopamine D2 agonism and will reduce the postsynaptic effects of dopamine
depletion to give symptomatic relief. There are also several mechanisms where by
adenosine A2A antagonists may be neuroprotective, for example by preventing glutamate
excitotoxicity, that may cause damage to dopaminergic neurons. A number of adenosine A2A
antagonists have already reached clinical trials and promising results were obtained,
especially when combined with levodopa. Consequently, A2A antagonists are realistic
prospects that have therapeutic potential in diseases with dopaminergic hypofunction, like
Parkinson's disease. Many of the current A2A antagonists contain an amino-substituted
heterocyclic scaffold, such as an aminopyrimidine. The primary aim of this study was the
design, synthesis and evaluation of 2-aminopyrimidine derivatives as adenosine A2A receptor
antagonists.
Monoamine oxidase B (MAO-B) inhibitors are also promising candidates for the symptomatic
treatment of Parkinson's disease, since MAO-B is the enzyme primarily responsible for the catabolism of dopamine in the brain. Irreversible inhibitors of MAO-B, such as selegeline and
rasagiline, have been used clinically for the treatment of Parkinson's disease. This type of
inhibition comes with certain disadvantages as it may take up to several weeks after
termination of treatment for the enzyme activity to recover. Reversible inhibitors in contrast
will have much better safety profiles seeing that they will not inactivate the enzyme
permanently and allow for competition with the substrate.
When dopamine is oxidized by MAO, toxic metabolic by-products, such as hydrogen
peroxide (H2O2) forms, and this is believed to be a possible cause of Parkinson's disease.
MAO-B inhibitors will therefore not only provide symptomatic relief but may also alter the
progression of the disease by preventing the formation of these byproducts. Promising MAOB
inhibitory activities have been reported for chalcones, and since the intermediates
obtained in the synthesis of aminopyrimidines in this study are chalcones, a secondary aim
of this study was the screening of selected chalcone intermediates as inhibitors of MAO–B.
Results -
Design and synthesis: A series of 2-aminopyrimidines were designed using known active
structures and literature pharmacophores. A molecular modelling study (Discovery Studio
3.1, Accelrys) was further done to investigate the feasibility of these compounds as potential
adenosine A2A antagonists. All of the designed aminopyrimidines were successfully docked
in the binding site of the adenosine A2A receptor. Binding orientations and observed
interactions with important residues in the active site were similar to those observed for
known A2A antagonists. It was therefore concluded that these compounds may be potential
A2A antagonists and the designed compounds were thus synthesised. Structures were
primarily confirmed with nuclear magnetic resonance spectroscopy and mass spectrometry.
MAO-B inhibition studies: Selected chalcones were evaluated using a fluorometric assay
and kynuramine as substrate. The compounds were potent and selective inhibitors of the
MAO-B enzyme with IC50 values ranging between 0.49-7.67 μM. (2E)-3-(3-Chlorophenyl)-1-
(5-methyl-2-furyl)prop-2-en-1-one (1c) was the most potent compound with an IC50 value of
0.49 μM and was approximately 60 times more selective towards MAO-B than MAO-A.
Some preliminary structure activity relationships were derived, for example, phenyl
substitution with an electron withdrawing chlorine group generally resulted in better activity
than substitution with electron donating methoxy groups. Further investigation of structure
activity relationships are however required as a very small series of chalcones were
screened.
Reversibility studies and mode of inhibition: A dilution assay was used to determine whether
compound (1c) binds reversibly or irreversibly to the MAO-B enzyme. This was done by measuring the recovery of enzymatic activity after a large dilution of the enzyme-inhibitor
complex. The results from the reversibility studies showed that the inhibition of the most
potent compound (1c) is reversible as the catalytic activities are recovered to approximately
80% and 50% respectively, compared to the control measured in the absence of an inhibitor.
For the mode of inhibition, sets of Lineweaver–Burk plots were constructed. The Lineweaver-
Burk plots intersected on the y-axis which indicates that compound 1c is a competitive inhibitor
of the MAO-B enzyme.
In vitro adenosine A2A assays: Radioligand binding assays were used to determine the
affinity of the synthesised 2-aminopyrimidines for the adenosine A2A receptor. This assay
was performed with the radioligand [3H]NECA in the presence of N6-cyclopentyladenosine
(CPA). Compounds 2a - 2h showed moderate to weak affinity in the assay, while promising
affinities were observed for compounds 2j - 2n, which all exhibited Ki values below 55 nM.
The compound with the highest affinity was 4-(5-methylfuran-2-yl)-6-[3-(piperidine-1-
carbonyl)phenyl]pyrimidin-2-amine (2m) with a Ki value of 5.76 nM, which is comparable to
the Ki value of 2.10 nM obtained for the known amino-substituted heterocyclic adenosine A2A
antagonist, ZM 241385. The higher affinities of compounds (2j – 2n) could, at least in part,
be explained by the molecular modellling studies. In the docking experiments an additional
hydrogen bond interaction was observed between the amide carbonyl and tyrosine 271
indicating that this structural feature is a major contributing factor to the improved affinity
observed for these derivatives.
In vivo adenosine A2A assays: The haloperidol induced catalepsy assay was used to
determine whether the two compounds with the highest affinity for the adenosine A2A
receptor (2m and 2k) are antagonists of the A2A receptor. These compounds caused a
statistically significant reduction in catalepsy, which clearly illustrate that they are adenosine
A2A antagonists.
The objectives of this study as set out were thus successfully realised and promising results
were obtained. During this study, several novel 2-aminopyrimidines and chalcones were
synthesised, and the respective adenosine A2A antagonistic and monoamine oxidase
inhibitory activities for all of the screened compounds were determined for the first time.Thesis (MSc (Pharmaceutical Chemistry))--North-West University, Potchefstroom Campus, 2013
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LELIEVRE, PHILIPPE. "Syntheses d'inducteurs potentiels de genes de virulence : alpha et beta-o-glucosides de coumarines, alpha-o-glucosides de phenols, benzalacetones et chalcones." Amiens, 1996. http://www.theses.fr/1996AMIE0104.
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Le but de ce travail a ete realiser la synthese d'alpha et beta-o-glucosides d'hydroxycoumarines, et d'alpha-o-glucosides de phenols, benzalacetones et chalcones. Dans une partie bibliographique, nous avons recence les principales methodes de o-glycosylation en nous attachant a degager la stereoselectivite de chaque reaction, et la diversite des aglycones greffes. Ainsi, ayant synthetise certaines hydroxycoumarines, la reaction de michael nous a permis d'acceder aux beta-o-glucosides correspondants de facon stereospecifique. Trois methodes d'alpha-o-glucosylation se sont averees efficaces : a partir du chlorure de 2,3,4,6-tetra-o-acetyl-beta-d-glucopyranosyle, les alpha-glucosides sont obtenus avec des rendements corrects, avec une stereoselectivite variable, due a l'anomerisation in situ de l'halogenure de depart. Les fluorures de 2,3,4,6-tetra-o-acetyl-d-glucopyranosyles ont donnes des rendements en glucoside similaires aux precedents, mais avec une meilleure stereoselectivite. Les meilleurs resultats ont ete obtenus a partir des phenylsulfoxydes de glucopyranosyles tetrabenzyles. Les alpha-o-glucosides purs ont ete isoles avec des rendements nettement superieurs a ceux obtenus precedemment. L'acces direct aux alpha-o-glucosides de benzalacetones et chalcones n'ayant pas pu etre realise, une voie indirecte a ete developpee. Celle-ci consiste a glycolyser une cetone ou un aldehyde phenolique, puis a realiser l'aldolisation. Les tests biologiques realises au laboratoire d'androgenese et biotechnologie d'amiens, ont permis de degager certains parametres structuraux necessaires pour que la molecule ait une activite inductrice de transfert de genes de virulence.
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Cheng, Chung-chin. "Syntheses and photophysics of luminescent polynuclear coinage metal complexes with chalcogen and pnictogen containing bridging ligands /." Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B22956372.
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AOUAD, MOHAMMED EL ARABI. "-d-o-glycosides de phenols, chalcones, benzalacetones et esters de -d-glucosyle d'acides phenoliques. Syntheses et activites comme inducteurs de genes de virulence." Amiens, 1994. http://www.theses.fr/1994AMIES041.
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La methode de michael a ete utilisee pour la synthese de -o glycosides d'aryle afin de pouvoir etudier leurs activites comme inducteurs de genes de virulence. Ainsi ont ete synthetises 22 glycosides de derives phenoliques ayant une structure proche de celle de l'acetosyringone. Ensuite, des cetones , ethyleniques comme des chalcones, des benzalacetones et des dibenzalacetones ont ete preparees et glycosylees. Pour les chalcones dihydroxylees, la methode de michael a permis la glycosylation du cote du noyau phenolique portant un ou deux groupes methoxy. Pour acceder au greffage de l'autre cote, nous avons du realiser d'abord la glycosylation d'une cetone ou d'un aldehyde phenolique puis l'aldolisation de ces glycosides. L'acces direct aux -d-o-glycosides d'aryle a ete recherche par une methode originale sans protection prealable de la partie sucre. Il est possible de preparer des derives 1,2-sulfite cyclique et de le faire reagir ensuite avec un ion phenate pour obtenir le -o-glucoside stereoselectivement. Cette methode one pot ne necessite donc aucun groupe protecteur et nous a permis en particulier d'acceder directement a des -d-o-xylosides. Deja une grande majorite de ces produits ont ete testes au laboratoire d'androgenese et biotechnologie d'amiens et il a pu etre degage quelques caracteristiques structurales necessaires a leur efficacite comme inducteurs de genes de virulence
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Long, Nicholas James. "Synthetic and spectroscopic studies on transition metal complexes of chalcogen-containing ferrocene and ruthenocene ligands." Thesis, University of Exeter, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235980.
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Sanz, Camacho Paula. "Synthetic, spectroscopic and structural studies of chalcogen peri-substituted heterocycles : a solid-state NMR perspective." Thesis, University of St Andrews, 2016. http://hdl.handle.net/10023/15854.
Full textAbstract:
Chalcogen-containing materials are an area of increasing interest for spintronic applications. The synthesis, structures and reactivity of these novel compounds are normally studied by solution-state nuclear magnetic resonance (NMR) spectroscopy, density functional theory (DFT) calculations and single-crystal X-ray diffraction. In this thesis, a range of chalcogen-containing heterocycles has been explored, focussing on the solid-state nature and exploring the bulk samples. Therefore, all materials were studied by powder X-ray diffraction and solid-state NMR, in addition to conventional solution-state NMR and single-crystal X-ray diffraction. DFT calculations were also used to interpret the solid-state NMR spectra and to gain insight into the NMR parameters. In the first chapter of results, a series of mixed Te, Se acenaphthenes is investigated. 77Se and 125Te NMR parameters are explored to determine whether changes in the Te aryl-group have an impact on the local environments of both nuclei. Dynamics and the requirement to consider relativistic effects for calculations of NMR parameters of heavy atoms is discussed. In the second results chapter, a series of novel P-S and P-Se six-membered heterocycles are described in terms of their synthesis, reactivity, and 31P and 77Se local environments. We observed and measured some unusual “through-space” couplings that occur between molecules and which mechanism and pathways are supported by DFT calculations. In the third results chapter, these heterocycles are oxidised with O, S and Se and the NMR parameters are discussed in terms of the structure. Polymorphism, phase transitions and weak interactions are some of the phenomena present in these novel compounds. This thesis demonstrated that solid-state NMR is a very good probe to study Se- and Te-containing materials.
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Medu, Erere Ohwofasa. "Examination of the antibacterial activities of some semi-synthetic chalcone-derivatives alone and in combination with polymyxin B." Thesis, Robert Gordon University, 2013. http://hdl.handle.net/10059/832.
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In view of the increasing global challenge of bacterial resistance, there exists an urgent need for the rationale development of antibacterial compounds with either novel or multiple mechanisms of action. Two chalcone-derivatives, F1 and F23, demonstrated MICs within the range of 16 to >512 μg/ml against two plant pathogens (P. caratovoram and C. michiganensis subsp. michiganensis) as well as important clinical bacterial species. Both compounds displayed an MIC of 32 μg/ml against quinolone-resistant S. aureus. Whilst possessing weak activities individually, each semi-synthetic agent displayed notable synergistic action with polymyxin B against S. aureus, C. violaceum, E. coli and Ps. aeruginosa, thereby recording FICs within the range of <0.093 to 2 that indicated the existence of synergism in some instance. These chalcone compounds applied with polymyxin B displayed a notable FICindex of <0.093 against the Neisseriaceae C. violaceum, and a potential noteworthy capacity to extend the spectrum of activity of the latter antibiotic to include Gram-positive S. aureus species. F1 inhibited staphylococcal replication in broth and the combination of either of both chalcone-derivatives with polymyxin B instituted a metabolic blockage in S. aureus and other bacterial species as determined through a modified MTT reduction assay. The combined agents inflicted major disruptions to the S. aureus cytoplasmic membrane bilayer as evidenced by the release of intracellular potassium as well as the influx of Sytox Green fluorescent stain. Notable levels of cell membrane potential dissipation, leakage of intracellular potassium ions and blockage of reducing enzymes activities occurred within the first 30 minutes, well in advance of significant loss in cell viability that was recorded usually after 4 – 8 hours, suggesting these activities were prerequisites to cell death. In erythrocyte lysis assay, the synergistic combinations of 128 μg/ml of either of both chalcone derivatives with 128 μg/ml polymyxin B displayed the lowest degree of haemolysis, followed by that occurring with 32 μg/ml of the chalcone-derivatives combined with 256 μg/ml of the polypeptide antibiotic. In conclusion, further structure activity modifications aimed at improving the aqueous solubility of these chalcone-derivatives as well as the antibacterial activity recorded for certain combination concentrations of polymyxin B with either of these semi-synthetic agents may be required before considerations are made for the possibility for potential external formulations. Such preparations may include antiseptic creams, lotions, ointments, as well as aerosols that can be applied with nebulizers in targeted delivery for such cases like cystic fibrosis.
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Athukorala, Arachchige Kasun S. "Synthesis and crystallographic studies of novel organotin acenaphthene compounds." Thesis, University of St Andrews, 2014. http://hdl.handle.net/10023/6363.
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Organic frameworks with rigid backbones, such as acenaphthene, are highly suitable for the study of interatomic interactions. The short “natural” peri-distance (2.44 Å) and the rigidity of the aromatic system causes considerable steric strain between peri-substituted heteroatoms. As a consequence, substitution at both peri-positions leads to in- and out-of-plane distortions, which often result in buckling of the ring system. In order to relax this geometric strain, weak bonding interactions can also exist between the peri-substituents. This thesis focuses on the synthesis, structural characterisation and investigation of a range of sterically crowded peri-substituted acenaphthene compounds. This involves the study of the acenaphthene geometry, through X-ray crystallography when different peri-substituents occupy the close 5,6-positions; our main focus is to study weak non-bonded interactions that can occur across the peri-gap, for example weakly attractive three-centre four-electron (3c-4e) type interactions which are known to prevail in such compounds under the appropriate conditions. Repulsion within these systems, resulting from the steric crowding of the peri-space is also investigated, employing changes in bond lengths, bay-region angle splay, displacement of atoms from the mean plane and central acenaphthene torsion angles to help quantify the degree of acenaphthene distortion, which are all conveniently probed by the peri-distance. To this end we have synthesised a range of novel sterically crowded mixed bromo-tin acenaphthene derivatives (Chapter 3), chalcogen-tin acenaphthene molecules (Chapter 4), phosphorus–tin derivatives (Chapter 5) and a series of homologous tin-tin acenaphthenes (Chapter 6). All the compounds studied in this thesis were characterised by multinuclear NMR spectroscopy and X-ray crystallography in an effort to gain a greater understanding of the deformation that occurs when disparate functionalities are located in close proximity and explore the potential for weak non-covalent intramolecular interactions to occur.
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Lam, Chi-ho Aaron. "Syntheses, characterization and photophysics of polynuclear copper (I) and silver (I) complexes containing monoynyl, diynyl and chalcogen-type ligands /." Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B22055034.
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Diamond, Louise M. "Synthetic, structural and spectroscopic studies of peri-substituted systems and their complexes." Thesis, University of St Andrews, 2014. http://hdl.handle.net/10023/6135.
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The family of polycyclic aromatic hydrocarbons naphthalene, acenaphthene and acenaphthylene, containing rigid organic backbones, allow the study of non-bonded intramolecular interactions. Due to the rigid framework, heteroatoms that are substituted at the peri-positions (positions 1- and 8- of the naphthalene ring and positions 5- and 6- of the acenaphthene and acenaphthylene rings) are forced to occupy space that is closer than the sum of their van der Waals radii, resulting in severe steric strain and unique interactions. In spite of this, a vast amount of peri-substituted naphthalenes have been prepared, however acenaphthene and acenaphthylene compounds have received much less attention. Preparation of these sterically crowded systems is possible because of the backbones ability to relieve strain as a result of both attractive and repulsive interactions. Attractive interactions relax the backbone via formation of weak or strong bonds between the substituents. Alternatively, repulsive interactions can result in the deformation of the backbone away from its natural geometry by buckling the ring system and causing the peri-bonds to distort in-plane and out-of-plane. Peri-substituted systems can also ease strain by forming compounds with bridging atoms or through bidentate coordination to form metal complexes with, for example, metal bis(phosphine) or bis(thiolate) moieties. The competition between attractive and repulsive forces, the method by which peri-substituted compounds relieve steric strain, is investigated in this thesis using a variety of different peri-moieties and the aforementioned organic backbones. Chapter 2 initially focuses on the formation of a series of platinum bis(phosphine) complexes, constructed from corresponding peri-substituted naphthalenes, 1,8-naphthosultone and 1,8-naphthosultam, the chemistry of which is outlined in Chapter 1. A corresponding study of platinum bis(phosphine) complexes, constructed from analogous 5,6-dihydroacenaphtho[5,6-cd]-1,2-dithiole and 5,6-dihydroacenaphtho[5,6-cd]-1,2-diselenole bidentate ligands is provided in Chapter 6. The chemistry of peri-substituted naphthalenes is well documented and a number of reviews have been written on this subject. Chapter 3, meanwhile, reviews the chemistry of related acenaphthene and acenaphthylenes which have seen increasing use in the literature over the last few years. Chapter 4 investigates the relationship between repulsive and attractive interactions that occur between the peri-substituents in a series of bis-chalcogen, mixed chalcogen-chalcogen and mixed halogen-chalcogen acenaphthylenes. By comparison with their known naphthalene and acenaphthene counterparts, the effect the rigid aromatic ring system has on the molecular geometry is examined. Finally, Chapter 5 looks at a series of acenaphthene and acenaphthylene compounds containing ArTe peri-substituents and explores how repulsive and attractive interactions affect molecular conformation and Te•••Te spin-spin coupling constants.
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Knight, Fergus Ross. "Synthesis and structural studies of group 16 peri-substituted naphthalenes and related compounds." Thesis, University of St Andrews, 2010. http://hdl.handle.net/10023/962.
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Understanding how atoms interact is a fundamental aspect of chemistry, biology and materials science. There have been great advances in the knowledge of covalent and ionic bonding over the past twenty years but one of the major challenges for chemistry is to develop full understanding of weak interatomic/intermolecular forces. This thesis describes fundamental studies that develop the basic understanding of weak interactions between heavier polarisable elements. The chosen methodology is to constrain heavy atoms using a rigid naphthalene backbone. When substituents larger than hydrogen, are positioned at close proximity at the peri-positions of a naphthalene molecule they experience steric strain; the extent of which is dictated by intramolecular interactions. These interactions can be repulsive due to steric hindrance or attractive due to weak or strong bonding. In efforts to understand the factors which influence distortion in sterically crowded naphthalenes and study possible weak intramolecular interactions between peri-atoms, investigations focussed on previously unknown mixed 1,8-disubstituted naphthalene systems. Mixed phosphorus-chalcogenide species were initially studied; three mixed phosphine compounds of the type Nap[ER][PPh2] were prepared along with their chalcogenides and a series of metal complexes. The study of interactions between heavy atoms was progressed by investigations into a series of mixed chalcogenide compounds of the type Nap[EPh][E’Ph] (E = S, Se, Te). Subsequent reaction of the chalcogenide systems with the di-halogens, dibromine and diiodine, afforded a mixture of charge transfer and insertion adducts displaying an array of different geometries around the chalcogen atom. From molecular structural studies, a collection of intramolecular peri-interactions were found, extending from no interaction due to repulsive effects, weak attractive 3c-4e type interactions and one example containing a strong covalent peri-bond. Further weak intramolecular interactions observed include CH-π and E•••E’ type interactions plus π-π stacking between adjacent phenyl rings. It was discovered that the bulk of the peri-atoms is influential on the distance between them, but this is not the only factor determining the naphthalene geometry. Inter- and intramolecular interactions can also have an impact and furthermore the number, size and electronic properties of substituents attached to the peri-atoms can determine molecular distortion.
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Gates, Derek Patrick. "The synthesis, structures, reactivity and polymerization behavior of boron- and sulfur-nitrogen-phosphorus heterocycles and highly strained chalcogen- and boron-bridged (1)ferrocenophanes." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0017/NQ45824.pdf.
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Robinson, Michael W. "Synthesis and Evaluation of Inducers of Methuotic Cell Death and Preliminary Identification of Their Cellular Targets in Glioblastoma Cells." University of Toledo Health Science Campus / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=mco1372430209.
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Back, Davi Fernando. "Estudo sobre a síntese e caracterização de clusters binários e ternários de organocalcogenetos contendo metais de transição." Universidade Federal de Santa Maria, 2008. http://repositorio.ufsm.br/handle/1/4156.
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Conselho Nacional de Desenvolvimento Científico e TecnológicoThis work presents a study related to the synthesis and characterization of a series of clusters with chacogen-metal bonds in which the metals are mercury, silver, cobalt, nickel, palladium, cadmium and zinc. The synthetic strategy is based on the combination a building block, bis-(phenyltellurium)mercury(II), (Hg(TePh)2), as the starting material, with a series of co-ligands and metal salts. In the synthesis of the fourteen clusters presented in this work, evidence of redistribution reactions was observed and, for some syntheses, disproportion reactions occurred concomitantly. In this study the following clusters were obtained: [Hg5(PhTe)7Br3]n;[Hg6(PhTe)15Te2Ag4]n; [Hg4(TePh)7IPy]n;[Hg4(SePh)7IPy]n;[Hg8(TePh)14Te(PPhMe2)2]·DMF; [Hg11(TePh)18Te2(Py)3]·Py2;[Hg6(PhTe16)Ag4];[Hg2(TePh)4Ag2(Cl2)]n; [Hg6(TePh)16Ag4Py4]·H2O;[Hg8Te(TePh)12Cl4]-2[Ni(DMF)6]+2; {[Zn(H2O)2(OH)2]@[Hg16(TePh)32]};[Pd2(TePh)2Cl2(PPh3)2]; [Hg8Te(TePh)12Cl4]-2[Co(DMF)6]+2 and {[Cd(H2O)2(OH)2]@[Hg16(TePh)32]}. The clusters were characterized by single crystal X-ray diffraction, elemental analysis and electron microscopy with X-ray dispersive energy spectroscopy. For some clusters, thermogravimetric analysis was carried out to test their stability.
Este trabalho apresenta um estudo relacionado com a síntese e caracterização de uma série de clusters contendo ligações de organocalcogenetos e metais de transição como mercúrio, prata, cobalto, níquel, paládio, cádmio e zinco. A metodologia de síntese baseou-se na utilização de um bloco de montagem básico, o bis(feniltelureto) de mercúrio (Hg(TePh)2), como material de partida e uma série de coligantes além de diferentes sais de metais. Na formação dos 14 clusters apresentados neste trabalho, houve evidências de reações de redistribuição e oxi-redução. Os clusters obtidos neste trabalho foram: [Hg5(PhTe)7Br3]n; [Hg6(PhTe)15Te2Ag4]n; [Hg4(TePh)7IPy]n; [Hg4(SePh)7IPy]n; [Hg8(TePh)14Te(PPhMe2)2]·DMF; [Hg11(TePh)18Te2(Py)3]·Py2; [Hg6(PhTe16)Ag4]; [Hg2(TePh)4Ag2(Cl2)]n; [Hg6(TePh)16Ag4Py4]·H2O; Hg8Te(TePh)12Cl4]-2[Ni(DMF)6]+2; {[Zn(H2O)2(OH)2]@[Hg16(TePh)32]}; [Pd2(TePh)2Cl2(PPh3)2]; [Hg8Te(TePh)12Cl4]-2[Co(DMF)6]+2 e {[Cd(H2O)2(OH)2]@[Hg16(TePh)32]}. Estruturalmente estes clusters foram caracterizados através da difração de raios-x em monocristal. Além disso, para todos os compostos incluem-se os resultados de análise elementar, espectroscopia de energia dispersiva de raios-x (EDX) e microscopia eletrônica de varredura. Para alguns dos clusters também foram realizados testes de estabilidade térmica através da análise de termogravimetria.
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Rosa, Gonçalo Pereira. "Chalcones : synthesis, bioactivities and biotransformation." Master's thesis, 2018. http://hdl.handle.net/10400.3/4617.
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Dissertação de Mestrado, Ciências Biomédicas, 01 de fevereiro de 2018, Universidade dos Açores.As calconas são compostos carbonílicos a,ß-insaturados que ocorrem na natureza e que apresentam uma ampla variedade de aplicações farmacêuticas e industriais. Devido à cada vez maior atenção que a sociedade tem mostrado pelos problemas ambientais, é altamente recomendável que sejam aplicados métodos de síntese e de transformação mais amigos do ambiente. Um dos métodos ecológicos que pode ser aplicado é a biotransformação, que recorre às capacidades das enzimas e/ou microrganismos para modificar as propriedades biológicas e físico químicas dos compostos. Todos estes factos têm estimulado um grande interesse na síntese, nas atividades biológicas e na biotransformação de calconas. Neste trabalbo, foram sintetizadas por condensação aldólica, 2'-hidroxicalconas com diferentes padrões de substituição com grupos hidroxilo e metoxilo, usando pela primeira vez hidreto de sódio (NaH) ou LiHMDS como base. O método mais eficiente para a síntese de calconas foi aquele em que NaH foi utilizado como base, mas a desproteção dos grupos hidroxilo diminui acentuadamente o rendimento final. O LiHMDS permitiu a síntese de polibidroxicalconas em apenas um passo, o que é uma vantagem, mas os rendimentos foram baixos. Os compostos sintetizados foram avaliados pelas suas atividades antioxidante, anticolinesterásica, antibacteriana e antitumoral, e foram estabelecidas relações estruturalatividade, com a 2',4',4 trihidroxicalcona a mostrar ser o composto mais ativo em termos de atividade antioxidante, anti-butirilcolinesterase e antibacteriana. A 4',7-dihidroxiflavanona inibe ambas as colinesterases, o que é bastante interessante em termos de terapia da Doença de Alzheimer. Também foi efetuada a preparação de um extrato enzimático rico em peroxidase, extraído de Brassica rapa L. bem como a otimização dos seus parâmetros operacionais. Este extrato enzimático não foi capaz de biotransformar nenhuma das calconas testadas, mas catalisa a biotransformação de acetofenonas, que são precursoras do anel aromático A das calconas. Esta biotransformação consiste na bidroxilação do C-6' numa modificação indeterminada no grupo metilo do C-2, as quais só ocorrem se o C-4' já estiver hidroxilado.
ABSTRACT: Chalcones are naturally occurring a,ß-unsaturated carbonyl compounds presenting a wide range of pharmaceutical and industrial applications. Due to our society's increasing attention to environmental problems, the application of eco-friendly methods in synthesis and transformation reactions is higbly desirable. One green approach is biotransformation, which makes use of the capabilities of enzymes and/or microorganisms to modify physicochemical and biological properties of compounds. These facts stimulate vast interest in synthesis, activities and biotransformation of chalcones. ln this work, 2'-hydroxychalcones with different hydroxyl and methoxyl substitution patterns were synthesized by aldol condensation, for the first time using sodium hydride (NaH) or LiHMDS as base. The most efficient method for chalcone synthesis was the one where NaH is the base, but deprotection of hydroxyl groups exerts a marked decrease in the final yield. LiHMDS allowed the one-pot synthesis of polyhydroxychalcones, which is an advantage, but the yields were low. The synthesized compounds were evaluated for antioxidant, anticholinesterasic, antibacterial and antitumor activities, and structure/activity relationships were established, with 2',4',4 trihydroxychalcone being the most active compound in the antioxidant, antibutyrylcholinesterase and antibacterial activities. 4'-7-Dihydroxyflavanone is able to inhibit both cholinesterases, which is very interesting in terms of Alzheimer's Disease therapy. The extraction of a peroxidase rich enzymatic extract from Brassica rapa L. and optimization of its working parameters was also performed. This enzymatic extract is not able to biotransform any chalcone tested but catalyzes the biotransformation of the acetophenones, precursors of chalcones ring A, by hydroxylation of C-6' and an undetermined modification of C-2 methyl group, when the C-4' is hydroxylated.
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Teng, Chi-Huang, and 鄧志煌. "Design, Synthesis and Cytotoxic Activities of Anthraquinones and Chalcones." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/67392882610079555670.
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博士高雄醫學大學
藥學研究所博士班
94
Natural anthraquinones and chalcones exhibited various biological activities. Some anthraquinones mediated their cytotoxicity through apoptosis. In previous reports, a series of anthraquinones were evaluated for their cytotoxicity. In order to understand the structure and cytotoxicity relationship, we continued to design and synthesize twenty one anthraquinone derivatives. In a previous study, we found that chalcone, 2'',5''-dimethoxy-4-hydroxychalcone (29) had significantly cytotoxic activity, therefore we had also to design and synthesize a series of chalcones, all of the compounds of anthraquinone and chalcone were evaluated for their cytotoxic activity and DNA strand scission activity. Anthraquinones were also evaluated for inhibitory effect on the platelet aggregation induced by epinephrine in human PRP. We also predicted their anti-cycloxygenase activity by molecular docking. Compound 3-[3-(4-Methylpiperazinopropoxy)]-9,10-anthraquinone (14) showed significantly cytotoxic activity against HT-29 and MCF-7. MCF-7 were treated with various concentrations of 14 for different time periods. The appearance of cells with low DNA stainability formed a “sub-G1 peak” and DNA fragmentation in MCF-7 cells was significantly observed after 72 hrs. These compounds might induce cell death by apoptosis. Among chalcone derivatives, the chalcones which have thio moiety, 2'',5''-Dimethoxy-2-thienylchalcone (32), 2'',5''-Dimethoxy-3-thienylchalcone (33) and 2'',5''-Dimethoxy-2-(5-methylthienyl)chalcone (35) had potent cytotoxic activity against MCF-7. Compound 35 showed significantly cytotoxic activity against colorectal cancer cell line. A “sub-G1 peak” increased and nuclear fragmentation in MCF-7 cells was significantly observed after 72 hrs. We suggested that these compounds might also induce cell death by apoptosis. 1-Hydroxy-3-[3-(diethylamino)-2-hydroxypropoxy]-9,10-anthraqunione (44) mediated DNA breakage in the presence of Cu (II) (300, 200, 100 ?嵱). The convertion of supercoiled DNA to the relaxed form was inhibited with neocuproine, a Cu (I)-specific sequestering agent. The result suggested that Cu (I) was the essential intermediate in the 44 mediated DNA cleavage reaction. Compound 44 in the presence of Cu (II) induced DNA degradation was completely inhibited by the addition of KI and catalase while superoxide dismutase (SOD) did not protect the DNA from strand breakage. We suggested that compound 44 induce H2O2 and OH• generation in the presence of Cu (II) and subsequent damage to cellular DNA. In epinephrine induced platelet aggregation of human PRP, compounds 9, 17, 42 and 43 prevented secondary aggregations and suppressed the primary aggregation at high concentrations induced by epinephrine. We supposed that these compounds might partially inhibit the thromboxane synthesis. In the molecular docking, compounds with the high Ligscore2 and the Jain score more than 2.46, revealed anti-cyclooxygenase activity. The synthetic chalcones 30-38 had high Ligscore2 and their Jain score also more than 2.46. It suggested that they might reveal anti-cyclooxyganase activity. In epinephrine induced platelet aggregation of human PRP, compounds 32, 33 and 35 prevented secondary aggregations. We suggested that these compounds might partially inhibit the thromboxane synthesis.
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Neves, Marta Alexandra Oliveira Perro. "Prenylflavonoids and Chalcones: Synthesis and Evaluation of the Antitumor Activity." Tese, 2011. https://repositorio-aberto.up.pt/handle/10216/73675.
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Neves, Marta Alexandra Oliveira Perro. "Prenylflavonoids and Chalcones: Synthesis and Evaluation of the Antitumor Activity." Doctoral thesis, 2012. https://repositorio-aberto.up.pt/handle/10216/73675.
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Pinto, Patrícia Alexandra Soares. "Synthesis of bioactive chalcones aond their heterocyclic derivatives as potential antitumor agents." Master's thesis, 2016. http://hdl.handle.net/10316/36300.
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Huang, Chun-Chang, and 黃俊彰. "Synthesis of Naturally Occurring Chalcones Containing 2-Hydroxy-3-methylbut-3-enyl Group." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/46447875158362080023.
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Jesus, Ana Isabel Moreira de. "Haloaryl secondary metabolites from macroalgae as models for the synthesis of brominated chalcones and their derivatives." Dissertação, 2019. https://hdl.handle.net/10216/123105.
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Jesus, Ana Isabel Moreira de. "Haloaryl secondary metabolites from macroalgae as models for the synthesis of brominated chalcones and their derivatives." Master's thesis, 2019. https://hdl.handle.net/10216/123105.
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Maluleka, Marole Maria. "Synthesis, biological evaluation and molecular docking studies of novel indole- and benzofuran-chalcone and benzofuran-quinazoline hybrids as anticancer agents." Thesis, 2019. http://hdl.handle.net/10500/25821.
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Text in EnglishSpecially prepared 2-amino-5-bromo-3-iodoacetophenone and 5-bromo-2-hydroxy-3 iodoacetophenone were subjected to Claisen-Schmidt aldol condensation with benzaldehyde derivatives followed by sequential and/or one-pot palladium catalyzed Sonogashira cross coupling and heteroannulation of the 3-alkynylated intermediates to afford indole-chalcones and benzofuran-chalcones, respectively. The indole-chalcones derivatives were, in turn, subjected to trifluoroacetic anhydride in tetrahydrofuran under reflux to afford the corresponding 3-trifluoroacetyl substituted indole-chalcone derivatives. The coupling constant values (Jtrans) of about 16.0 Hz for the chalcone derivatives corresponding to the vinylic protons confirmed the trans geometry of the α,β-unsaturated carbonyl framework in all the cases. Their trans geometry of the chalcone derivatives was further confirmed by single crystal X-ray diffraction (XRD) analyses. Further structural elaboration of the ambident electrophilic α,β unsaturated carbonyl (chalcone) moiety of the indole-chalcones and the analogous benzofuran chalcones with 2-aminothiophenol afforded novel benzothiezapine-appended indole and benzofuran hybrids, respectively. Sonogashira cross-coupling of 5-bromo-2-hydroxy-3 iodoacetophenone with terminal acetylenes followed by heteroannulation of the intermediate 3-alkynylated 5-bromo-2-hydroxyacetophenones afforded the corresponding 7-acetyl-2-aryl-5-bromobenzofurans in a single-pot operation. The oximes derived from the 7-acetyl–substituted 2-aryl-5-bromobenzofurans were subjected to Beckmann rearrangement with triflic acid in acetonitrile under reflux. We isolated the corresponding 7-amino-2-aryl-5 bromobenzofuran derivatives formed from hydrolysis in situ of the intermediate 7-acetamide 2-aryl-5-bromobenzofurans. Amino-dechlorination of the 4-chloroquinazoline derivatives with the 7-aminobenzofurans afforded novel benzofuran 4-aminoquinazoline hybrids. The prepared compounds were characterized using a combination of nuclear magnetic resonance (1H-NMR & 13C-NMR including 19F-NMR), infrared (IR) and mass spectroscopic techniques complemented with single crystal X-ray diffraction (XRD) analyses and/or density functional (DFT) method. The benzofuran-chalcone 203a–y derivatives were evaluated for anti-growth effect against the breast cancer (MCF-7) cell line by the MTT cell viability assay. Their mode of cancer cell death (apoptosis versus necrosis) was detected by Annexin V-Cy3 SYTOX staining and caspase-3 activation. The most cytotoxic compounds 203i and 203o were also evaluated for potential to inhibit tubulin polymerization and/or epidermal growth factor receptor-tyrosine kinase (EGFR-TK) phosphorylation. The experimental results were complemented with theoretical data from molecular docking into ATP binding site of the EGFR and colchicine binding site of tubulin, respectively. The benzofuran–4-aminoquinazoline hybrids 215a–j, on the other hand, were evaluated for antiproliferative propeties in vitro against the human lung cancer (A549), epithelial colorectal adenocarcinoma (Caco-2) and hepatocellular carcinoma (C3A) cell lines. The benzofuran-aminoquinazoline hybrids were also evaluated for potential to induce apoptosis and for their capability to inhibit EGFR-TK phosphorylation complemented with molecular docking (in silico) into the ATP binding site of EGFR. Mechanistic studies demonstrated that the benzofuran-appended aminoquinazoline hybrids 215d and 215j induced apoptosis via activation of caspase-3 pathway. Moreover, compounds 215d and 215j exhibited significant and moderate inhibitory effects against EGFR (IC50 = 29.3 nM and 61.5 nM, respectively) when compared to Gefitinib (IC50 = 33.1 nM). Molecular docking of compounds 215 into EGFR-TK active site suggested that they bind to the region of EGFR like Gefitinib does.
Chemistry
D. Phil. (Chemistry)
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Lee, Chang-Min, and 李長民. "The Synthesis of Isobarachalcone and the Study of Synthetic Methodology of Chalcone." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/81599402906209978961.
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碩士朝陽科技大學
應用化學系碩士班
89
The derivatives of chalcone have varies pharmacological activity. For example, some chalcone are potential germicides, and useful as sweeteners, with effective against the aggregation of rabbit platelet activating factor etc. According to the literature, isobarachalcone was isolated from Chinese herbs, Psoralea Corylifolia L., has showed the ability to inhibit the aggregation of the platelet. This research will be designed to synthesise isobarachalcone as well as the study of the synthetic methodology of chalcone.
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Lee, Tai-Hua, and 李泰華. "Design,Synthesis and Antiplatelet Effects of Chalcone." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/77111124573300345768.
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Chien, Chun-Kai, and 簡君愷. "Synthesis and characterization of chalcone-containing benzoxazine." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/76181071001805425180.
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碩士國立中興大學
化學工程學系所
103
The photosensitive chalcone-containing benzoxazine (2) was synthesized successfully from chalcone-containing bisphenol, aniline and paraformaldehyde by one-pot procedure. The [2+2] cycloaddition of the chalcone moiety after UV irradiation was monitored by FTIR and UV-vis spectra. To investigate the effect of photodimerization on thermal and mechanical properties, two steps curing procedure was performed. After the cycloaddition of the chalcone moiety by UV-irradiation, the ring-opening polymerization of benzoxazine was performed by thermal curing. Due to the enhancement of the crosslink density, the UV-irradiated thermosets exhibit good thermal and mechanical properties.
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Liu, Cheng-Tsung, and 劉政宗. "Synthesis and Biological Activity of Chalcone Derivatives." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/01509704118093870420.
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碩士高雄醫學大學
藥學研究所
90
In a continual screening on anti-inflammatory agents, we reported brousschalcone A, a natural chalcone of Broussonetia papyrifera, showed a potent inhibitory effect on release of lysozyme from rat neutrophils. So we have synthesized a series of chalcone derivatives and related compounds 1-11, which were prepared by Claisen-Schmidt Condensation of appropriate acetophenones with appropriate aromatic aldehydes, and studied on their anti-inflammatory effects. The anti-inflammatory activities of these synthetic compounds were studied on inhibitory effects on the activation of mast cells, neutrophils, macrophages and microglial cells. Chalcones 1 and 2 showed strong inhibitory effects on the release of β-glucuronidase and histamine from rat peritoneal mast cells stimulated with compound 48/80. Chalcones 1-6 and 9 exhibited inhibitory effects on the release of β-glucuronidase and lysozyme from rat neutrophils stimulated with formyl-Met-Leu-Phe (fMLP). Chalcones 1-5 showed inhibitory effects on superoxide formation of rat neutrophils stimulated with fMLP/cytochalasin B, while 1 and 3 indicated weak inhibitory effects on superoxide formation of rat neutrophils stimulated with phorbol myristate acetate (PMA). Chalcones 1, 5 and 6 exhibited inhibitory effects on nitric oxide (NO) formation from macrophage like cell line RAW 264.7 cells stimulated with lipopolysaccharide (LPS) and murine microglial cell line N9 stimulated with LPS/interferon (IFN-γ). Chalcones 2, 3 and 5 showed distinctively inhibitory effects on tumor necrosis factor (TNF-α) formation from N9 cell line caused by LPS/ IFN-γ. The present results demonstrated most of the chalcone derivatives have anti-inflammatory effects. The main mechanism of these compounds is mediated through the suppression of chemical mediators released from mast cells and neutrophils. The inhibitory effects is not only mediated through the suppression of chemical mediators released from mast cells and neutrophils, but also that of NO formation from macrophage and microglial cells.
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Yu, Kun-Lung, and 游昆龍. "Synthesis and Anti-inflammatory Activity of Chalcone Derivatives." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/08179229109419278859.
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碩士高雄醫學大學
藥學研究所
88
For a continued study of structure-activity relationship of various chalcone derivatives designed as anti-inflammatory agents, we have synthesized a series of new chalcone derivatives and related compounds, 1-11, and studied on their anti-inflammatory effects. All the chalcones and related compounds were prepared by Claisen- Schmidt Condensation of appropriate acetophenones with appropriate aromatic aldehydes. Alkoxylchalcones were prepared by appropriate dihydroxylchalcones and alkyl iodides. One flavone was synthesized by appropriate acetophenone with benzoyl chloride through Baker- Venkataraman rearrangement. The anti-inflammatory activities of these synthetic compounds were studied on inhibitory effects on the activation of mast cells, neutrophils, macrophages and microglial cells. Chalcones, 3, 4, 6, 8, showed strong inhibitory effects on the release of β-glucuronidase and histamine from rat peritoneal mast cells stimulated with compound 48/80. Chalcones, 1, 2, 3, 4, 6, 8, exhibited potent inhibitory effects on the release of β-glucuronidase and lysozyme from rat neutrophils stimulated with formyl-Met-Leu-Phe (fMLP). Chalcones, 1, 2, 3, 4, 6, 10, showed potent inhibitory effects on superoxide formation of rat neutrophils stimulated with fMLP/cytochalasin B(CB) while 8 indicated weak inhibitory effects on superoxide formation of rat neutrophils stimulated with phorbol myristate acetate(PMA). Compounds 1 and 5, alkoxychalcones, exhibited potent inhibitory effects on nitric oxide (NO) formation from macrophage like cell line RAW 264.7 cells stimulated with lipopolysaccharide (LPS) and murine microglial cell line N9 stimulated with LPS/interferon (IFN)-γrespectively. Compound 11, a flavone, showed distinctively inhibitory effects on tumor necrosis factor (TNF)-α formation from N9 cell line caused by LPS/ IFN-γ. The present results demonstrated most of the chalcone derivatives have anti-inflammatory effects. The inhibitory effects of these compounds on inflammation are partly mediated through the suppression of chemical mediators released from mast cells and neutrophils. The inhibitory effects of dialkoxychalcones on inflammation are probably not only due to the inhibition of mast cells and neutrophils degranulation, but also are mediated partially through the suppression of NO formation from N9 cell. These findings suggested that some chalcones might probably have beneficial effects on the central neurodegenerative disorders observed in aging and Alzheimer’s disease.
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Machado, Carmen Mariana Pimenta Carvalho. "Antitumor chalcone derivatives: synthesis and biological activity evaluation." Dissertação, 2017. https://hdl.handle.net/10216/108596.
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Machado, Carmen Mariana Pimenta Carvalho. "Antitumor chalcone derivatives: synthesis and biological activity evaluation." Master's thesis, 2017. https://hdl.handle.net/10216/108596.
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