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Paiva, Raphael Enoque Ferraz de 1989. "Complexos metálicos com nimesulida : síntese, caracterização e aplicações em química bioinorgânica medicinal". [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/249124.
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Orientador: Pedro Paulo CorbiDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química
Made available in DSpace on 2018-08-25T01:00:34Z (GMT). No. of bitstreams: 1 Paiva_RaphaelEnoqueFerrazde_M.pdf: 15807547 bytes, checksum: e13f0a8a3bbde08ba558ac7cdb13c9a5 (MD5) Previous issue date: 2014
Resumo: Complexos metálicos têm sido estudados quanto as suas propriedades medicinais há décadas. Neste trabalho, dois complexos inéditos de Ag(I) e Pt(II) foram sintetizados com o anti-inflamatório nimesulida (NMS), e avaliados como agentes antibacterianos e antitumorais. O complexo Ag-NMS (AgC13H11N2O5S) apresenta o ligante em uma coordenação bidentada à prata pelos átomos de N e O do grupo sulfonamida. A estrutura proposta foi confirmada por DFT. Devido à baixa solubilidade em água, foi preparado um complexo de inclusão de Ag-NMS em b-CD, pelo método de co-evaporação. Utilizando o método de Scatchard, foi determinado o valor de Ka = 370 2 L mol. Estudos de RMN por correlação H-H através do espaço mostram que a inclusão ocorre pelo grupo fenoxi da NMS. Já o complexo Pt-NMS (PtC26H22N4O10S2) apresenta dois ligantes, coordenados pelos átomos de N e O do grupo sulfonamida, para cada Pt(II). A DFT indica que o isômero N, O trans é o mais estável. O complexo Ag-NMS apresentou valores de MIC na faixa de 15,0-120 mmol L sobre cepas de Pseudomonas aeruginosa, Escherichia col e Staphylococcus aureus. O CE-[(Ag-NMS)·b-CD], embora mais solúvel em água do que o Ag-NMS, não apresentou atividade antibacteriana nas concentrações testadas. Os complexos Ag-NMS e Pt-NMS mostraram-se citotóxicos sobre células normais (Balb/c 3T3) e tumorais (SK-Mel 103 e Panc-1), porém o Pt-NMS foi significativamente mais seletivo contra as linhagens tumorais. Os ensaios de intercalação com EtBr e a avaliação da estrutura do DNA por dicroísmo circular indicam que o DNA não é um alvo biológico para o complexo Pt-NMS, indicando um mecanismo de ação diferente da cisplatina
Abstract: Metal complexes have been studied regarding its medicinal properties for decades. In this work, novel complexes of Ag(I) and Pt(II) with the anti-inflammatory nimesulide were synthesized and evaluated regarding their antibacterial and antitumoral properties. The Ag-NMS complex (AgC13H11N2O5S) shows the ligand in a bidentate coordination mode, bound to silver through the N and O atoms of the sulfonamide group. The proposed structure was confirmed by DFT. Due to its poor solubility in water, the Ag-NMS complex was included in b-CD, by co-evaporation. The Ka = 370 2 L mol was determined using the Scatchard method. Studies by H-H NMR correlation through space shows the inclusion of NMS by the fenoxi group. The Pt-NMS complex (PtC26H22N4O10S2) contain two ligands, coordinated through the N and O atoms of the sulfonamide group, for each Pt(II). DFT studies indicate that the N,O trans isomer is the most stable. The Ag-NMS complex presents MIC values in the range 15.0-120 mmol L over Pseudomonas aeruginosa, Escherichia coli e Staphylococcus aureus. The inclusion complex CE-[(Ag-NMS)·b-CD], although more soluble in water than Ag-NMS, shows no antibacterial activity in the tested concentrations. Both complexes were cytotoxic against normal (Balb/c 3T3) and tumor (SK-Mel 103 and Panc-1) cells, but the Pt-NMS complex was significantly more selective against tumor cells. The EtBr competitive intercalation assay and the evaluation of CT-DNA structure using circular dichroism show that DNA is not a biological target for the Pt-NMS complex, indicating a mechanism of action different of the cisplatin one
Mestrado
Quimica Inorganica
Mestre em Química
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Karges, Johannes. "Design, Synthèse, Caractérisation et Evaluation Biologique de Complexes Métalliques pour la Thérapie Photodynamique à un et deux Photons". Thesis, Paris Sciences et Lettres (ComUE), 2019. http://www.theses.fr/2019PSLEC028.
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Le cancer est un problème de santé majeur dans le monde entier. Les statistiques des dernières décennies des organismes internationaux GLOBOCAN et OMS ont montré que le cancer est la cause principale de mortalité dans les pays développés et la deuxième maladie la plus meurtrière dans les pays en voie de développement. Dans les pays développés, ce phénomène peut s’expliquer par une croissance et un vieillissement de la population et l’adoption d’un mode de vie malsain comme par exemple le tabagisme ou encore l’inactivité physique. Alors que le nombre de patients diagnostiqués d’un cancer augmente d’année en année, le traitement et l’espérance de vie des patients ont été considérablement améliorés. Aujourd’hui, les traitements classiques contre le cancer sont la chirurgie, la chimiothérapie, l’immunothérapie et la radiothérapie qui peuvent être utilisés seuls ou en association. Pour diminuer les effets secondaires de ces traitements et augmenter la survie du patient, de nombreux efforts de recherche sont actuellement consacrés au développement de nouvelles stratégies thérapeutiques et de nouveaux médicaments. Parmi elles, la thérapie photodynamique (PDT, l’acronyme de l’anglais photodynamic therapy) a récemment fait l’objet d’une attention croissante en tant que technique complémentaire pour le traitement de divers cancers. La PDT consiste à administrer au patient un médicament photoactivable nommé photosensibilisateur. Ce médicament est, ensuite, activé localement après une exposition à la lumière. Les médicaments actuellement approuvés cliniquement ont une capacité limitée, en raison de leur faible stabilité biologique, solubilité et sélectivité vis-à-vis des cellules tumorales. Dans ce travail, différents types de nouveaux complexes métalliques ont été étudiés en tant que potentiels photosensibilisateurs pour surmonter les limitations actuellement rencontrées en PDTCancer is and remains a major health problem all around the world. Statistics over the last decades of GLOBOCAN and WHO shows that it is the leading cause of death in developed countries and the second most lethal disease in non-developed countries. It is suggested that the increasing impact of cancer on the life expectation and life quality in developed countries is a result of population aging and growth and adoption of an unhealthy life style such as for example smoking or physical inactivity. While the number of reported patients diagnosed with cancer is from year to year rising, significant improvements in the treatment and life expectations of patients were made. To date, cancer is commonly treated by surgery, chemotherapy, immunotherapy, radiotherapy or a combination of these to overcome the limitations of a single treatment. To attenuate the side effects of such treatments and to increase the overall survival of the patient, much research efforts are currently devoted towards the development of new therapeutic strategies and drugs. Recently, photodynamic therapy (PDT) has received increasing attention as a complementary technique for the treatment of a variety of cancers. During a therapeutic session, a photoactivable drug is administered to a patient. Afterward, this drug is locally activated upon light exposure. Despite the success of the currently approved drugs, the ability of these are limited, among others, due to their poor biological stability, solubility and cancer selectivity. To overcome these limitations, in this work, different types of new metal complexes were investigated as potential drug candidates
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Keter, Frankline Kiplangat. "Pyrazole and pyrazolyl palladium(II) and platinum(II) complexes: synthesis and in vitro evaluation as anticancer agents". Thesis, University of the Western Cape, 2004. http://etd.uwc.ac.za/index.php?module=etd&.
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The use of metallo-pharmaceuticals, such as the platinum drugs, for cancer treatment illustrates the utility of metal complexes as therapeutic agents. Platinum group metal complexes therefore offer potential as anti-tumour agents to fight cancer. This study was aimed at synthesizing and evaluating the effects of palladium(II) and platinum(II) complexes as anticancer agents.
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Pettenuzzo, Nicolò. "Steps forwards to a new type of oncotherapy: from the solution chemistry of Au(III)-dithiocarbamato complexes to the design and development of innovative Au(III)- and Cu(II)-based cancer-targeting agents". Doctoral thesis, Università degli studi di Padova, 2018. http://hdl.handle.net/11577/3426685.
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In order to overcome the side effects of the chemotherapy, but remaining firmly convinced in the powerful role of the medicinal inorganic chemistry, Fregona’s research group, since 2000, developed a series of metal-based dithiocarbamato molecules, in particular containing Au(III), Ru(III) and Cu(II) metal centers, which are highly active in vitro toward a great number of human tumor cell lines and less toxic in vivo, compared to other chemotherapeutics. Although several insights into the chemistry of these powerful coordination compounds were performed in last years, some aspects remain to be elucidating.
In the first part of this work, we present a comprehensive study concerning the synthesis, the characterization and the solution behavior of eight Au(III) dithiocarbamato complexes, revealing their peculiar and fascinating chemistry. Moreover, seven of them showed interesting biological properties in vitro toward a selected human tumor cell line.
The second part of the Ph.D. research was focused on the synthesis, characterization and biological evaluation of novel bio-conjugated Au(III) and Cu(II) complexes with the aim of improve the accumulation of the anticancer metal payload into malignant cells. In order to reach this goal, three different cancer-targeting agents were chosen and, on the whole, nine different complexes were synthetized and tested as anticancer agents.
Intriguingly, one of them proved a high cytotoxic activity toward a selected human tumor cell line, paving the way to future studies investigating the role of the cancer-targeting functionalization in the selective targeting of the complex toward cancerous tissues.Al fine di superare gli effetti collaterali della chemioterapia, ma rimanendo fortemente convinti del ruolo potente che può svolgere la chimica inorganica applicata alla medicina, la Prof.ssa Fregona e i suoi collaboratori si sono occupati, fin dai primi anni 2000, dello sviluppo di una serie di molecole a base metallica con leganti ditiocarbammici, in particolare contenenti centri metalli quali Au(III), Ru(III) e Cu(II). Queste si sono rivelate altamente attive in vitro verso un gran numero di linee cellulari tumorali umane e meno tossiche, in vivo, rispetto ad altri chemioterapici di uso clinico. Benchè negli ultimi anni siano stati condotti diversi studi approfonditi sulla chimica di questi potenti composti di coordinazione, alcuni aspetti rimangono ancora da spiegare. Nella prima parte di questo lavoro, si presenta uno studio completo sulla sintesi, la caratterizzazione e sulla chimica in soluzione di otto complessi ditiocarbammici di Au(III), che hanno rivelato una reattivià peculiare ed affascinante. Inoltre, sette di essi hanno dimostrato interessanti proprietà biologiche in vitro verso una linea cellulare tumorale del cancro colon-rettale. Nella seconda parte del progetto di dottorato, il lavoro si è focalizzato sulla sintesi, la caratterizzazione e la valutazione biologica di nuovi complessi ditiocarbammici di Au(III) e Cu(II), bioconiugati con una funzione molecolare targettante, con l'obiettivo di migliorare l’accumulo di questa classe di molecole all’interno delle cellule cancerose. Al fine di raggiungere questo obiettivo, sono stati scelti tre differenti agenti di targeting, che sfruttano il diverso metabolismo delle cellule neoplastiche rispetto a quelle sane. Nel complesso, sono stati sintetizzati nove diversi composti di coordinazione che sono stati testati come agenti antitumorali in vitro. Fra questi, uno di loro ha dimostrato un'elevata attività citotossica contro una linea cellulare tumorale, aprendo la strada a futuri studi che indagheranno il ruolo della funzionalizzazione targettante nel delivery selettivo del complesso verso i tessuti cancerosi.
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PAIOTTA, ALICE. "Synthesis of Glycoderivatives as Molecular Tools in Medicinal Chemistry and Nano-Medicinal Chemistry". Doctoral thesis, Università degli Studi di Milano-Bicocca, 2018. http://hdl.handle.net/10281/199137.
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Durante il terzo anno di dottorato mi sono occupata della sintesi finale dei glicomimetici del substrato naturale dell’enzima AGM1 GlcNAc-6P o del prodotto GlcNAc-1P.
Le sintesi messe a punto sono necessarie per ottenere prodotti finali utilizzabili come strumenti molecolari chimici per studiare il ruolo dell’HBP nella regolazione della proliferazione e la sopravvivenza delle cellule tumorali.
I prodotti presentati (caratterizzati mediante NMR (1H. COSY, HSQC e 13C) e Massa) sono stati preparati protetti (acetilati sugli ossidrili) per i test cellulari per favorire la loro diffusione attraverso la membrana cellulare e nella forma de-protetta per il test enzimatico, per poterne valutare la potenza inibitoria direttamente sull’enzima AGM1.
La messa a punto del test enzimatico ha come obiettivo la valutazione dell’effettiva capacità inibitoria dei composti sintetizzati. Il test prevede la comparazione della quantità di UDP-GlcNAc prodotto dalla reazione accoppiata dell’enzima AGM1 e AGX1, utilizzando un estratto enzimatico cellulare, in assenza e in presenza dei potenziali inibitori. La quantificazione è stata effettuata mediante l’utilizzo della tecnica cromatografica HPLC, con un metodo ion-pair a fase inversa associato ad un rilevatore UV impostato ad una lamda di 254 nm.
Inizialmente è stata preparata la retta di taratura dell’UDP-GlcNAc costruita partendo da una madre 1.5 mM e attraverso diluzioni sono state effettuate le analisi in triplicato per ogni punto della retta. Sono stati calcolati i valori del limite di rilevabilità (LOD) e di quantificazione (LOQ).
Il test messo a punto prevede la quantificazione della produzione di UDP-GlcNAc a partire dai substrati GlcNAc-6P e UTP utilizzando estratti cellulari lisati. In una prima analisi si è esaminato l’estratto enzimatico per verificare la presenza di UDP-GlcNAc endogena, che non è stata riscontrata. Quindi si è verificata l’effettiva efficacia dell’estratto nel catalizzare la produzione di UDP-GlcNAc a partire dai substrati forniti e si sono messe a punto le condizioni di reazione. Infine, si è proceduto con l’analisi degli inibitori sintetizzati. Dati preliminari non hanno evidenziato una diminuzione del segnale di UDP-GlcNAc, il che farebbe escludere una buona attività inibitoria.
Durante il periodo di Traineeship presso il CycloLab di Budapest ho potuto effettuare l'incapsulamento di un potenziale inibitore enzimatico in ciclodestrine funzionalizzate per il targeting di cellule tumorali.
Alcuni dei composti sintetizzati possiedono caratteristiche chimico-fisiche che rendono il loro passaggio attraverso la membrana cellulare molto difficile: la presenza di gruppi solfati, solfonati e fosforamidati, che possiedono cariche negative, li rendono particolarmente polari. Lo scopo del progetto è quello di sfruttare ciclodestrine (CD) opportunamente funzionalizzate come un “cavallo di Troia” per veicolare gli inibitori enzimatici all'interno delle cellule tumorali.
Al CycloLab mi sono quindi occupata della sintesi dello scaffold di interesse e dell’incapsulamento del potenziale inibitore.The project carried out during the 3 years-Ph.D. has had the objective to identify and synthesize new glycomimetics as molecular tools to study the Hexosamine Biosynthetic Pathway (HBP), which role is to regulate the proliferation and survival of cancer cells. The project has been funded by AIRC and the principal aim was to identify the Adenocarcinoma of the Pancreatic Duct (PDAC) as the target of research. The synthesis of innovative chemical tools helps the understanding of the HBP pathway and its response in PDAC: new potential inhibitors, which are similar to the natural substrate of enzyme, can be recognized but trick the enzyme and block its activity in order to decrease the UDP-GlcNAc production and consequently modify the protein glycosylation. Due to the important role of the HBP in the cells, alteration of this pathway can bring to alteration of N- and O- glycosylation and activate the Unfolded Protein Response (UPR) during the Endoplasmic Reticulum (ER) stress. The description of the research target helps the understanding of the design of molecular tools: the focus point is the inhibition of the enzyme N-acetylglucosamine-phosphate mutase (AGM1): its inhibition could represent the way to induce apoptosis in cancer cells. Through the Molecular Design, a rational design of potential inhibitors has been done. This design is based on the similarity with the structures of the natural substrate of enzyme AGM1, with some modifications. All of the drawn structures have been used for Molecular Docking in order to get a first virtual screening on the compounds library. Starting from preliminary results of theoretical approach, the synthesis of compounds have been done following three different synthetic strategies. All the steps and reaction condition are described in details and are shown the characterization (1H, 13C NMR spectra, m/z) of all the synthetized compound. The optimization of the analytical method on High Performance Liquid Chromatography is necessary in order to achieve experimental data on the ability of the designed compounds to inhibit the target enzyme, data to be compared to those obtained through a computational theoretical approach. To this aim an HPLC method has been set-up for the quantification of UDP-GlcNAc produced using the cellular extract as enzyme source, and carrying out the reaction with the natural substrates GlcNAc-6P, UTP in the presence or not of the test molecules. Using 10 and 30 µL of extract, three compounds lead to a decrease of production of UDP-GlcNAc. The computational data ”describes” the interaction between the enzyme and the molecules. The calculation of C LogP has confirmed the most apolar character of compound 3B in the acetylated form. Some preliminary evaluation of the effect of compound 2B in a Triple Negative Breast Cancer (TNBC) cell model has been carried out. In conclusion, the study of the target of this research, the HBP pathway, and the focus on the inhibition of AGM1 are the starting point for a complete project, that includes at first the design of a library of compound based on the structural properties of the natural substrate. the “in silico” evaluation of their interaction with the target enzyme, the synthesis and the screening through an enzymatic assay.. The tuning of the strategy of synthesis is important to obtain the compound for the in vitro test. The analytical method with HPLC gives results comparable to the docking scores, and then, after a calculation of C LogP, the test on cells gives the final results of potency of compound 3B (2B the acetylated form). The last part describes the collaboration with CycloLab (Budapest): some compounds of the library possess chemical-physical characteristics that make their passage through cell membrane very harsh: they are very polar and some of them possess negative charges (sulphate, sulphonates, phosphoramidate). This preliminary work is still in progress.
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Brophy, Megan Brunjes. "Bioinorganic Chemistry of the Human Host-Defense Protein Calprotectin". Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/98823.
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Thesis: Ph. D. in Biological Chemistry, Massachusetts Institute of Technology, Department of Chemistry, 2015.Vita. Cataloged from PDF version of thesis.
Includes bibliographical references.
The human innate immune system responds to bacterial and fungal pathogens by releasing the metal-chelating protein calprotectin (CP) at sites of infection and in the upper layers of the epidermis. CP is a Mn(II)- and Zn(ll)-binding protein. The work described in this thesis elucidates the metal-binding properties of CP, and correlates these properties with in vitro growth inhibition of bacteria and fungi. We report that the metal-binding properties of CP are modulated by Ca(ll), and we propose a working model in which CP responds to physiological Ca(Il)-ion gradients to become a potent Zn(ll)- and Mn(Il)-chelating agent in the extracellular space. Individual chapter summaries follow. Chapter 1: Bioinorganic Chemistry of the Host Pathogen Interaction. Transition metal ions are required for all forms of life. During the course of infection, pathogenic microorganisms must acquire transition metals from the host. Three metals of interest from this standpoint are iron, zinc, and manganese. This chapter describes bacterial metal-ion homeostasis machineries, and metal-requiring processes with a focus on Zn(II) and Mn(II). This chapter then highlights the S100 family of Ca(ll)-binding proteins and discuses the Zn(Il)-, Cu(ll)-, and Mn(Il)-binding properties of S100B, S100A12, S100A7, S10OA15, and S100A8/S100A9. Finally, an overview of the scope of this thesis is presented. Chapter 2: Calcium Ion Gradients Modulate the Zinc(Il) Affinity and Antibacterial Activity of Human Calprotectin. Calprotectin (CP) is a human neutrophil protein that is produced and released by neutrophils at sites of infection, where it prevents the growth of microorganisms by sequestering bioavailable zinc(II) and manganese(II). In this chapter, we present metalbinding studies to elucidate the Zn(ll)-binding properties of CP. We report unique optical absorption and EPR spectroscopic signatures for the interfacial His 3Asp and His 4 sites of human CP by using Co(II) as a spectroscopic probe. Zinc competition titrations employing colorimetric and fluorimetric Zn(II) sensors establish that CP coordinates two Zn(II) ions / CP heterodimer. The Ca(ll)-insensitive Zn(ll) sensor ZP4 is used to determine the Kd of CP for Zn(II) in Ca(Il)-deplete and Ca(Il)-replete conditions. These competition titrations afford apparent Kdsitel = 133 58 pM and Kdsite2 = 185 219 nM in the absence of Ca(II). In the presence of excess Ca(Il) these values decrease to Kd,sitel 5 10 pM and Kd,site2 : 240 pM. In vitro antibacterial assays indicate that the metal-binding sites and Ca(ll)-replete conditions are required to inhibit the growth of Gram-negative and Gram-positive bacteria. We propose a model in which Ca(II) ion gradients modulate the antibacterial activity and Zn(Il)-binding properties of human CP. Chapter 3: High-Affinity Manganese Coordination by Human Calprotectin Is Calcium- Dependent and Requires the Histidine-Rich Site at the Dimer Interface. In this chapter, we report that the His 4 motif at the S10OA8/S100A9 dimer interface of CP is required for high-affinity Mn(II) coordination. We identify a low-temperature EPR spectroscopic signal for this site that is consistent with high-spin Mn(II) in an octahedral coordination sphere. This site could be simulated with zero-field splitting parameters D = 270 MHz and EID = 0.30 (E = 81 MHz). This analysis, combined with studies of mutant proteins, suggests that (A8)Hisl7, (A8)His27, (A9)His9l, (A9)His95 and two as-yet unidentified ligands coordinate Mn(ll) at site 2. These studies support a model in which CP responds to Ca(ll) ion gradients to become a potent metal-ion chelator in the extracellular space. Chapter 4: Contributions of the C-terminal Tail of S100A9 to High-Affinity Manganese Binding by Human Calprotectin. This chapter examines the role of the S100A9 C-terminal tail to high-affinity Mn(ll) coordination by human CP. We present a 16-member mutant family with mutations in the S100A9 C-terminal tail (residues 96-114), which houses three histidine and four acidic residues, to evaluate its contribution to Mn(ll) sequestration. These studies confirm that two His residues at positions 103 and 105 complete the octahedral coordination sphere of CP in solution. Appendix 1: Sequence Alignments of Transition-Metal Binding S100 Proteins. Sequence alignments of S100A7, S100A8, S100A9, S100A12, S100A15, and S100B proteins from multiple organisms are presented. Appendix 2: Characterization of CP Mutant Proteins by Circular Dichroism and Analytical Size Exclusion Chromatography. Additional characterization of CP and mutant proteins employed in Chapters 2-4 is presented. Appendix 3: Structures of Sensors Used In this Work. The structures of Zincon, MagFura-2, Zinpyr-1, and Zinpyr-4 are presented. Appendix 4: Manganese Binding Properties of Human Calprotectin under Conditions of High and Low Calcium. This appendix represents a collaborative work with the Drennan Lab (MIT) and Britt Lab (UC Davis) to study the Mn(Il)-CP complex in low- and high-Ca(II) conditions. We report a crystal structure of Mn(Il)-, Ca(Il)-, and Na(l)-bound CP with Mn(II) exclusively coordinated to the His6 motif. Electron spin-echo envelope modulation and electron-nuclear double resonance experiments demonstrate that the six coordinating histidine residues are spectroscopically equivalent. The observed 15N ( = %/h)y perfine couplings (A) arise from two distinct classes of nitrogen atoms: the coordinating E-nitrogen of the imidazole ring of each histidine (A = [3.45, 3.71, 5.91] MHz) and the distal 6-nitrogen (A = [0.11, 0.18, 0.42] MHz). In the absence of Ca(II), the affinity of CP for Mn(II) drops by two to three orders of magnitude, and Mn(II) coordinates to the His6 site as well as other sites on the protein.
by Megan Brunjes Brophy.
Ph. D. in Biological Chemistry
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Uchiyama, Mayara Klimuk. "Estudo de nanopartículas de ouro e de magnetita voltadas para medicina diagnóstica". Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/46/46136/tde-18092015-104822/.
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A teragnóstica de doenças tem sido extremamente marcada nos últimos anos por nanomateriais formados pela conjugação de nanopartículas a biomoléculas, pois a aplicação de tecnologias baseadas em materiais na dimensão nanométrica é capaz de aumentar a seletividade, sensibilidade e praticidade dos métodos atualmente empregados, ou mesmo criar novos métodos de diagnóstico e tratamento de doenças. Dentre os vários tipos de nanomateriais desenvolvidos, aqueles baseados em nanopartículas de ouro ou nanopartículas magnéticas apresentam propriedades químicas e físicas diferenciadas que propiciam novas possibilidades. Por exemplo, a presente tese demonstrou que nanopartículas superparamagnéticas são excelentes agentes de contraste em exames de imagem por ressonância magnética (IRM) por serem mais seguros, apresentarem melhor contraste nas imagens e possibilitarem direcionar/concentrar o material em tecidos ou tumores através de um gradiente de campo magnético aplicado. Foram feitos numerosos ensaios de toxicidade tanto in vitro quanto in vivo para assegurar a segurança da aplicação de nanopartículas no organismo, cujo potencial de uso somente se tornará uma realidade caso os nanomateriais se mostrem não tóxicos e biocompatíveis. Apesar dos significativos avanços na área da aplicação desses nanomateriais, não foram encontrados na literatura modelos capazes de explicar ou prever por quais sítios de ligação devem ocorrer as interações proteína-nanopartícula, como também não foram encontrados estudos sistemáticos acerca dos fatores que determinam a estabilidade e a funcionalidade dos nanobioconjugados (NBCs). Assim, nesta tese buscamos compreender os fatores responsáveis pela ligação/adsorção das proteínas nas nanopartículas de ouro e sua influência sobre a estabilidade das suspensões e a funcionalidade das proteínas. Desta forma, foram obtidos NBCs com propriedades adequadas para o desenvolvimento ou aprimoramento de ensaios de diagnóstico e até para o tratamento de doenças. Foi demonstrado o potencial das nanopartículas de ouro para melhorar a performance de imunoensaios do tipo ELISA, mas também podem ser utilizadas para o desenvolvimento de métodos de diagnóstico, explorando as propriedades plasmônicas das nanopartículas de ouro acopladas a técnicas como SERS, SPR e microscopia Raman confocal.Theranostics has been intensively pursued in recent years using hybrid materials based on nanoparticles conjugated with biomolecules. This is an interesting strategy to increase the selectivity and sensitivity, as well as to improve the currently used methods facilitating their use or creating new ones. Among the various types of nanomaterials, those based on gold and magnetic nanoparticles exhibit interesting chemical and physical properties in the biological environment, differing from that of free drugs or current explored in assay methods. For example, superparamagnetic nanoparticles are excellent contrast agents for magnetic resonance image (MRI) diagnostics because they are safer, present a better contrast efficiency for imaging and can be magnetically accumulated in tissues or tumors using a magnetic field. Numerous in vitro and in vivo toxicity assays were performed to ensure the safety for medical applications. Clearly, these type of applications only will be realized if nanomaterials prove to be nontoxic and biocompatible. This imply an strict control on their structure and composition. However, despite the significant advances in the development of such nanomaterials, there were not found in the literature model systems explaining or that can be used to predict by which sites the protein-nanoparticle binding should take place. In addition, no systematic studies on the factors determining the stability and the functionality of nanobioconjugates (NBC) were found. Thus, this thesis is focused in unveiling the factors responsible for binding/adsorption of proteins on gold nanoparticles and their influence on the colloidal stability of hybrid nanoparticles suspensions while keeping the functionality of biomolecules. In fact, NBC with enhanced properties suitable for the development of diagnostic methods and even for treatment of diseases were obtained. These nanomaterials can improve the ELISA immunoassay, or other diagnosis methods can be developed by using the gold nanoparticles plasmonic properties in association with SERS, SPR and confocal Raman microscopy techniques.
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Rajarathinam, Kayathri. "Nutraceuticals based computational medicinal chemistry". Licentiate thesis, KTH, Teoretisk kemi och biologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-122681.
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In recent years, the edible biomedicinal products called nutraceuticals have been becoming more popular among the pharmaceutical industries and the consumers. In the process of developing nutraceuticals, in silico approaches play an important role in structural elucidation, receptor-ligand interactions, drug designing etc., that critically help the laboratory experiments to avoid biological and financial risk. In this thesis, three nutraceuticals possessing antimicrobial and anticancer activities have been studied. Firstly, a tertiary structure was elucidated for a coagulant protein (MO2.1) of Moringa oleifera based on homology modeling and also studied its oligomerization that is believed to interfere with its medicinal properties. Secondly, the antimicrobial efficiency of a limonoid from neem tree called ‘azadirachtin’ was studied with a bacterial (Proteus mirabilis) detoxification agent, glutathione S-transferase, to propose it as a potent drug candidate for urinary tract infections. Thirdly, sequence specific binding activity was analyzed for a plant alkaloid called ‘palmatine’ for the purpose of developing intercalators in cancer therapy. Cumulatively, we have used in silico methods to propose the structure of an antimicrobial peptide and also to understand the interactions between protein and nucleic acids with these nutraceuticals.QC 20130531
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Pujar, P. P. "Chemistry of Indian medicinal plants". Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 1999. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/3410.
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Yan, Siu-cheong. "Bioinorganic chemistry of antimony : interaction of antimonial with biomolecules /". View the Table of Contents & Abstract, 2004. http://sunzi.lib.hku.hk/hkuto/record/B30575540.
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Seifert, S., i J. Van Den Hoff. "Annual Report 2004 - Institute of Bioinorganic and Radiopharmaceutical Chemistry". Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-28695.
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Seifert, S., i H. Spies. "Annual Report 2003 - Institute of Bioinorganic and Radiopharmaceutical chemistry". Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-28959.
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Johannsen, Bernd, i Sepp Seifert. "Institute of Bioinorganic and Radiopharmaceutical Chemistry; Annual Report 2002". Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-29271.
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Johannsen, Bernd, i Sepp Seifert. "Institute of Bioinorganic and Radiopharmaceutical Chemistry; Annual Report 2001". Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-29488.
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Seifert, Sepp, i Bernd Johannsen. "Institute of Bioinorganic and Radiopharmaceutical Chemistry; Annual Report 2000". Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-29716.
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Johannsen, Bernd, i Sepp Seifert. "Institute of Bioinorganic and Radiopharmaceutical Chemistry; Annual Report 1997". Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-30891.
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Seifert, Sepp, i Bernd Johannsen. "Institute of Bioinorganic and Radiopharmaceutical Chemistry; Annual Report 1996". Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-31238.
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Seifert, Sepp, i Bernd Johannsen. "Institute of Bioinorganic and Radiopharmaceutical Chemistry; Annual Report 1995". Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-31653.
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Johannsen, Bernd. "Institute of Bioinorganic and Radiopharmaceutical Chemistry; Annual Report 1994". Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-32143.
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Johannsen, Bernd. "Institute of Bioinorganic and Radiopharmaceutical Chemistry; Annual Report 1993". Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-32438.
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Johannsen, Bernd. "Institute of Bioinorganic and Radiopharmaceutical Chemistry; Annual Report 1992". Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-32587.
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Yan, Siu-cheong, i 甄肇昌. "Bioinorganic chemistry of antimony: interaction of antimonial with biomolecules". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B4457017X.
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Seifert, S., i J. Van Den Hoff. "Annual Report 2004 - Institute of Bioinorganic and Radiopharmaceutical Chemistry". Forschungszentrum Rossendorf, 2005. https://hzdr.qucosa.de/id/qucosa%3A21696.
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Seifert, S., i H. Spies. "Annual Report 2003 - Institute of Bioinorganic and Radiopharmaceutical chemistry". Forschungszentrum Rossendorf, 2004. https://hzdr.qucosa.de/id/qucosa%3A21722.
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Johannsen, Bernd, i Sepp Seifert. "Institute of Bioinorganic and Radiopharmaceutical Chemistry; Annual Report 2002". Forschungszentrum Rossendorf, 2003. https://hzdr.qucosa.de/id/qucosa%3A21754.
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Johannsen, Bernd, i Sepp Seifert. "Institute of Bioinorganic and Radiopharmaceutical Chemistry; Annual Report 2001". Forschungszentrum Rossendorf, 2002. https://hzdr.qucosa.de/id/qucosa%3A21775.
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Johannsen, Bernd, i Sepp Seifert. "Institute of Bioinorganic and Radiopharmaceutical Chemistry; Annual Report 1997". Forschungszentrum Rossendorf, 1997. https://hzdr.qucosa.de/id/qucosa%3A21916.
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Seifert, Sepp, i Bernd Johannsen. "Institute of Bioinorganic and Radiopharmaceutical Chemistry; Annual Report 1996". Forschungszentrum Rossendorf, 1997. https://hzdr.qucosa.de/id/qucosa%3A21950.
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Seifert, Sepp, i Bernd Johannsen. "Institute of Bioinorganic and Radiopharmaceutical Chemistry; Annual Report 1995". Forschungszentrum Rossendorf, 1996. https://hzdr.qucosa.de/id/qucosa%3A21992.
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Johannsen, Bernd. "Institute of Bioinorganic and Radiopharmaceutical Chemistry; Annual Report 1994". Forschungszentrum Rossendorf, 1995. https://hzdr.qucosa.de/id/qucosa%3A22041.
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Johannsen, Bernd. "Institute of Bioinorganic and Radiopharmaceutical Chemistry; Annual Report 1993". Forschungszentrum Rossendorf, 1994. https://hzdr.qucosa.de/id/qucosa%3A22070.
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Johannsen, Bernd. "Institute of Bioinorganic and Radiopharmaceutical Chemistry; Annual Report 1992". Forschungszentrum Rossendorf, 1993. https://hzdr.qucosa.de/id/qucosa%3A22085.
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Seifert, Sepp, i Bernd Johannsen. "Institute of Bioinorganic and Radiopharmaceutical Chemistry; Annual Report 2000". Forschungszentrum Rossendorf, 2001. https://hzdr.qucosa.de/id/qucosa%3A21798.
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Johannsen, B., i S. Seifert. "Institute of Bioinorganic and Radiopharmaceutical Chemistry, Report July - December 1999". Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-30041.
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Howson, Suzanne E. "Self-assembly and bioinorganic chemistry of optically pure helical complexes". Thesis, University of Warwick, 2011. http://wrap.warwick.ac.uk/35728/.
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Chapter 1 introduces the concept of helicates and the importance of chirality in these complexes. The different literature methods used to synthesise optically pure helicates are reviewed and their advantages and disadvantages discussed. Finally, a new approach towards synthesising diastereomerically pure helicatelike complexes is considered. Chapter 2 describes the syntheses of optically and diastereomerically pure factris( diimine) monometallic complexes of Fe(II) with d.r. > 200:1. The origins of this unprecedented stereo- and chemical selectivity are investigated via computational and structural studies, and compared with analogous complexes of other 3d metals (ZnII, CoII, CoIII). The reactivity of the optically and stereochemically pure Fe(II) complexes towards e.g. copper(I)-catalysed Huisgen 1,3-dipolar cycloaddition ‘click’ reactions is investigated. Recently published Cu(II) complexes of the same ligand by Min et al. are also discussed. Chapter 3 focuses on extending the chemistry described in Chapter 2 to design ligands capable of forming helicate-like structures. The resulting Fe(II) and Zn(II) bimetallic triple stranded complexes are diastereomerically pure with d.r. > 200:1. A detailed structural study is described based on a single crystal X-ray structure. The ability to add substituents to the pyridine rings successfully allows useful functionalities to be incorporated on the periphery of the structure. Chapter 4 describes the synthesis of a second family of diastereomerically pure helicate-like complexes. Useful functionalities are easily incorporated on the periphery of the structure via the use of different (R)-2-phenylglycinol derived amines in a one-pot synthesis. The reactivity of the alkyne hexa-functionalised Fe(II) complex towards copper(I)-catalysed Huisgen 1,3-dipolar cycloaddition reactions is also investigated. Chapter 5 focuses on the synthesis and biological applications of water soluble helicate-like bimetallic complexes. Specifically, experiments probing the binding of these complexes to DNA and DNA structural motifs are described. The antimicrobial activity of the complexes against the Gram-negative bacterium E. coli and the Gram-positive bacterium S. aureus (MRSA252) is also investigated. Chapter 6 details the experimental procedures used to carry out the work in this thesis.
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Johannsen, B., i S. Seifert. "Institute of Bioinorganic and Radiopharmaceutical Chemistry, Report July - December 1999". Forschungszentrum Rossendorf, 2000. https://hzdr.qucosa.de/id/qucosa%3A21831.
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Shi, Dong-Fang. "The medicinal chemistry of antitumour benzazoles". Thesis, University of Nottingham, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283645.
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Brown, Stacy D., Andy Coop, Paul Trippier i Eric Walters. "Contemporary Approaches For Teaching Medicinal Chemistry". Digital Commons @ East Tennessee State University, 2017. https://dc.etsu.edu/etsu-works/5251.
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As the profession of pharmacy has transitioned from a chemistry-centered profession to a patient-centered profession, the role of medicinal chemistry in the curriculum has evolved. There is decreased emphasis on memorization of chemical structures, and priority placed on relating these structures to ADME, physical properties, and pharmacodynamics. Simultaneously, the delivery of this content has shifted from traditional lecture format to other styles. Here we discuss some new approaches to teaching medicinal chemistry.
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Razavet, Mathieu. "Synthetic {2Fe3S} assemblies and the active site of all-iron hydrogenases". Thesis, University of East Anglia, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268566.
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Walton, Paul Howard. "The modelling of copper biosites". Thesis, University of Nottingham, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.276371.
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Kamp, Norbert W. J. "The catalytic oxidation of phenolic substrates using manganese triazacyclononane complexes and hydrogen peroxide". Thesis, University of York, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265366.
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Mars, Craig. "Small molecule models of nitrite reductase". Thesis, University of York, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270037.
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Schilter, David. "Synthesis and DNA-binding of Metallocyclic Architectures". Thesis, The University of Sydney, 2009. http://hdl.handle.net/2123/5317.
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A new family of cationic N-heterocyclic ligand derivatives was prepared and characterised. Among these compounds are halide salts of the dications [Y(spacer)Y]2+, each of which comprise two N heterocyclic donor groups (Y = 4,4′-bipy, pyz, apyz, apym) linked by a conformationally flexible spacer such as (CH2)n, α,α′-xylylene, 2,6-lutidylene or thiabicyclo[3.3.1]nonane-2,6 diyl. The diquaternary halide salts were converted to NO3- and PF6- salts, and interaction of these bridging ligands with labile palladium(II) and platinum(II) precursors afforded several multinuclear complexes. Bis(4,4′-bipyridinium) dications were incorporated into the dinuclear macrocycles [M2(2,2′ bipy)2{4,4′ bipy(CH2)n4,4′-bipy}2]8+ (M = Pd, Pt; n = 4, 6), cis [Pd2Cl4{4,4′ bipy(CH2)34,4′-bipy}2]4+, [Pt2(dppp)2{4,4′-bipy(1,2-xylylene)4,4′-bipy}2]8+ and cis-[Pt2Cl4{4,4′-bipy(1,2-xylylene)4,4′-bipy}2]4+. While bis(pyrazinium) analogues were unreactive towards the palladium(II) and platinum(II) precursors, the doubly deprotonated bis(3 aminopyrazinium) and bis(2 aminopyrimidinium) derivatives served as charge-neutral quadruply-bridging ligands in the complexes [Pt4(2,2′ bipy)4{apyz(CH2)6apyz–2H}2]8+ and [Pt4(2,2′ bipy)4{apym(CH2)5apym–2H}2]8+, both of which feature Pt(II). Pt(II) interactions. Larger species formed when the diamine O,O′-bis(2-aminoethyl)octadeca(ethylene glycol) (PEGda) was treated with cis dinitratopalladium(II) and platinum(II) precursors. The resulting complexes [M(N,N)(PEGda)]2+ (M = Pd, Pt; N,N = 2,2′-bipy, en, tmeda) possessed great size (62 membered chelate rings) and aqueous solubility. DNA-binding studies were conducted with selected complexes in order to investigate the types of interactions these species might participate in. Equimolar mixtures containing either the 16mer duplex DNA D2 or the single strand D2a and palladium(II)/platinum(II) complexes were prepared and analysed by negative-ion ESI MS. Studies of D2/Pd(II) mixtures suggested extensive fragmentation was occuring, and the use of [Pd(tmeda)(PEGda)]2+ and [Pd2(2,2′-bipy)2{4,4′-bipy(CH2)44,4′-bipy}2]8+ resulted in D2 adducts of [Pd(tmeda)]2+ and [4,4′-bipy(CH2)44,4′-bipy]2+, respectively. Decomposition also occurred when D2a was used, although 1 : 1 adducts were observed with [Pd(tmeda)(PEGda)]2+, [Pd(2,2′ bipy)(PEGda)]2+ and [Pd2(2,2′-bipy)2{4,4′-bipy(CH2)44,4′-bipy}2]8+. The low intensities of these adducts indicated that they are unstable towards ESI MS. Analogous ESI-MS experiments using platinum(II) derivatives were performed and, in contrast to those with palladium(II), indicated that the complexes remained largely intact. ESI-MS analysis of D2/Pt(II) mixtures allowed for the detection of 1 : 1 D2 adducts of [Pt(en)(PEGda)]2+, [Pt(tmeda)(PEGda)]2+ and [Pt2(2,2′-bipy)2{4,4′-bipy(CH2)44,4′-bipy}2]8+. Intensities of the adduct ions suggested the greater charge and aryl surface area allow the dinuclear species to bind D2 most strongly. Both [Pt(2,2′-bipy)(Mebipy)2]4+ and [Pt(2,2′ bipy)(NH3)2]2+ gave rise to 1 : 2 adducts of D2, although the latter was found to be a weaker binder, perhaps owing to its lower charge. Data obtained using 1 : 5 (D2 : complex) mixtures were consistent with the results above and suggested that D2 can bind more molecules of daunomycin than any of the platinum(II) species. Analyses of D2a/Pt(II) mixtures gave results similar to those obtained with D2, although fragmentation was more pronounced, indicating that the nucleobases in D2a play more significant roles in mediating decomposition than those in D2, in which they are paired in a complementary manner. Investigations into the effects of selected platinum(II) complexes on the thermal denaturation of calf-thymus DNA (CT-DNA) in solution were conducted. Both [Pt2(2,2′ bipy)2{4,4′-bipy(CH2)64,4′-bipy}2]8+ and [Pt(2,2′-bipy)(Mebipy)2]4+ greatly stabilised CT-DNA, most likely by intercalation. In contrast, [Pt(tmeda)(PEGda)]2+ and [Pt(en)(PEGda)]2+ (as well as PEGda) caused negligible changes in melting temperature (∆Tm), suggesting that these interact weakly with CT-DNA. Data for [Pt(2,2′ bipy)(PEGda)]2+ and [Pt(2,2′-bipy)(NH3)2]2+ indicated that these species perhaps intercalate CT-DNA, with similar ∆Tm values for both complexes implying that PEGda does not play a major role in binding. While findings from ESI-MS experiments were similar to those from the thermal denaturation experiments, discrepancies between results from the two methods could be found. In particular, fragmentation of cyclic species during ESI-MS caused the binding strength of the species to be underestimated when this method was employed.
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Schilter, David. "Synthesis and DNA-binding of Metallocyclic Architectures". University of Sydney, 2009. http://hdl.handle.net/2123/5317.
Pełny tekst źródłaStreszczenie:
PhDA new family of cationic N-heterocyclic ligand derivatives was prepared and characterised. Among these compounds are halide salts of the dications [Y(spacer)Y]2+, each of which comprise two N heterocyclic donor groups (Y = 4,4′-bipy, pyz, apyz, apym) linked by a conformationally flexible spacer such as (CH2)n, α,α′-xylylene, 2,6-lutidylene or thiabicyclo[3.3.1]nonane-2,6 diyl. The diquaternary halide salts were converted to NO3- and PF6- salts, and interaction of these bridging ligands with labile palladium(II) and platinum(II) precursors afforded several multinuclear complexes. Bis(4,4′-bipyridinium) dications were incorporated into the dinuclear macrocycles [M2(2,2′ bipy)2{4,4′ bipy(CH2)n4,4′-bipy}2]8+ (M = Pd, Pt; n = 4, 6), cis [Pd2Cl4{4,4′ bipy(CH2)34,4′-bipy}2]4+, [Pt2(dppp)2{4,4′-bipy(1,2-xylylene)4,4′-bipy}2]8+ and cis-[Pt2Cl4{4,4′-bipy(1,2-xylylene)4,4′-bipy}2]4+. While bis(pyrazinium) analogues were unreactive towards the palladium(II) and platinum(II) precursors, the doubly deprotonated bis(3 aminopyrazinium) and bis(2 aminopyrimidinium) derivatives served as charge-neutral quadruply-bridging ligands in the complexes [Pt4(2,2′ bipy)4{apyz(CH2)6apyz–2H}2]8+ and [Pt4(2,2′ bipy)4{apym(CH2)5apym–2H}2]8+, both of which feature Pt(II). Pt(II) interactions. Larger species formed when the diamine O,O′-bis(2-aminoethyl)octadeca(ethylene glycol) (PEGda) was treated with cis dinitratopalladium(II) and platinum(II) precursors. The resulting complexes [M(N,N)(PEGda)]2+ (M = Pd, Pt; N,N = 2,2′-bipy, en, tmeda) possessed great size (62 membered chelate rings) and aqueous solubility. DNA-binding studies were conducted with selected complexes in order to investigate the types of interactions these species might participate in. Equimolar mixtures containing either the 16mer duplex DNA D2 or the single strand D2a and palladium(II)/platinum(II) complexes were prepared and analysed by negative-ion ESI MS. Studies of D2/Pd(II) mixtures suggested extensive fragmentation was occuring, and the use of [Pd(tmeda)(PEGda)]2+ and [Pd2(2,2′-bipy)2{4,4′-bipy(CH2)44,4′-bipy}2]8+ resulted in D2 adducts of [Pd(tmeda)]2+ and [4,4′-bipy(CH2)44,4′-bipy]2+, respectively. Decomposition also occurred when D2a was used, although 1 : 1 adducts were observed with [Pd(tmeda)(PEGda)]2+, [Pd(2,2′ bipy)(PEGda)]2+ and [Pd2(2,2′-bipy)2{4,4′-bipy(CH2)44,4′-bipy}2]8+. The low intensities of these adducts indicated that they are unstable towards ESI MS. Analogous ESI-MS experiments using platinum(II) derivatives were performed and, in contrast to those with palladium(II), indicated that the complexes remained largely intact. ESI-MS analysis of D2/Pt(II) mixtures allowed for the detection of 1 : 1 D2 adducts of [Pt(en)(PEGda)]2+, [Pt(tmeda)(PEGda)]2+ and [Pt2(2,2′-bipy)2{4,4′-bipy(CH2)44,4′-bipy}2]8+. Intensities of the adduct ions suggested the greater charge and aryl surface area allow the dinuclear species to bind D2 most strongly. Both [Pt(2,2′-bipy)(Mebipy)2]4+ and [Pt(2,2′ bipy)(NH3)2]2+ gave rise to 1 : 2 adducts of D2, although the latter was found to be a weaker binder, perhaps owing to its lower charge. Data obtained using 1 : 5 (D2 : complex) mixtures were consistent with the results above and suggested that D2 can bind more molecules of daunomycin than any of the platinum(II) species. Analyses of D2a/Pt(II) mixtures gave results similar to those obtained with D2, although fragmentation was more pronounced, indicating that the nucleobases in D2a play more significant roles in mediating decomposition than those in D2, in which they are paired in a complementary manner. Investigations into the effects of selected platinum(II) complexes on the thermal denaturation of calf-thymus DNA (CT-DNA) in solution were conducted. Both [Pt2(2,2′ bipy)2{4,4′-bipy(CH2)64,4′-bipy}2]8+ and [Pt(2,2′-bipy)(Mebipy)2]4+ greatly stabilised CT-DNA, most likely by intercalation. In contrast, [Pt(tmeda)(PEGda)]2+ and [Pt(en)(PEGda)]2+ (as well as PEGda) caused negligible changes in melting temperature (∆Tm), suggesting that these interact weakly with CT-DNA. Data for [Pt(2,2′ bipy)(PEGda)]2+ and [Pt(2,2′-bipy)(NH3)2]2+ indicated that these species perhaps intercalate CT-DNA, with similar ∆Tm values for both complexes implying that PEGda does not play a major role in binding. While findings from ESI-MS experiments were similar to those from the thermal denaturation experiments, discrepancies between results from the two methods could be found. In particular, fragmentation of cyclic species during ESI-MS caused the binding strength of the species to be underestimated when this method was employed.
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Golden, Melissa Lynn. "The bioinorganic chemistry of N2S2 metal complexes: reactivity and ligating ability". Diss., Texas A&M University, 2002. http://hdl.handle.net/1969.1/2198.
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[N,N??-bis-(mercaptoethyl)-1,5-diazacyclooctanato]NiII, Ni-1, is known to undergo metallation reactions with numerous metals. [N,N??-bis-(mercaptoethyl)-1,5-diazacycloheptanato]NiII, (bme-dach)Ni or Ni-1??, differs from Ni-1 by one less carbon in its diazacycle backbone ring producing subtle differences in N2S2Ni geometry. Metallation of Ni-1?? with PdCl2, Pd(NO3)2, and NiBr2 produced three structural forms: Ni2Pd basket, Ni4Pd2 C4-paddlewheel, and Ni3 slant chair. In attempts to provide a rationale for the heterogeneity in the active site of Acetyl coA Synthase, metal ion capture studies of Ni-1 in methanol found a qualitative ranking of metal ion preference: Zn2+ < Ni2+ < Cu+. Formation constants for metal ion capture of Ni-1?? in water were determined for Pb2+, Ni2+, Zn2+, Cu+, and Ag+. A quantitative estimate places copper some 15 orders of magnitude above nickel or zinc in binding affinity. Sulfur dioxide uptake by Ni-1?? is characterized by significant color change, improved adduct solubility, and reversible binding of two equivalents of SO2. These combined properties establish Ni-1?? as a suitable model for gas uptake at nickel thiolate sites and as a possibly useful chemical sensor for this poisonous gas. Comparisons of molecular structures, ν(SO) stretching frequencies, and thermal gravimetric analyses are made to reported adducts including the diazacyclooctane derivative, Ni-1·2SO2. Visual SO2 detection limits of Ni-1 and Ni-1?? are established at 25 ppm and 100 ppm, respectively. Structural studies of products resulting from reaction at the nucleophilic S-sites of (bme-dach)Ni and [(bme-dach)Zn]2 included acetyl chloride and sodium iodoacetate as electrophiles are shown. The acetyl group is a natural electrophile important to the citric acid cycle. Acetylation of (bme-dach)Ni produces a five coordinate, paramagnetic species. Iodoacetate is a cysteine modification agent known to inhibit enzymatic activity. The reaction of (bme-dach)Ni and sodium iodoacetate yields a blue, six coordinate nickel complex in a N2S2O2 donor environment. The bismercaptodiazacycloheptane ligand binds lead(II) forming an unprecedented structural form of N2S2M dimers, in which Pb2+ is largely bound to sulfur in a highly distorted trigonal geometry. Its unusual structure is described in comparison to other derivatives of the bme-daco ligand. The synthesis and structural characterization of square pyramidal (bme-dach)GaCl are also given and compared to the analogous (bme-daco)GaCl.
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Johannsen, Bernd, i S. Seifert. "Institute of Bioinorganic and Radiopharmaceutical Chemistry; Report January 1998 - Juni 1999". Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-30215.
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Johannsen, Bernd, i S. Seifert. "Institute of Bioinorganic and Radiopharmaceutical Chemistry; Report January 1998 - Juni 1999". Forschungszentrum Rossendorf, 1999. https://hzdr.qucosa.de/id/qucosa%3A21848.
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Lyon, James Thomas III. "Chemical Studies on Oxomolybdenum(VI,IV) Complexes as Bioinorganic Models for the Molybdenum Oxidases". VCU Scholars Compass, 1985. https://scholarscompass.vcu.edu/etd/5227.
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The synthesis, characterization, and chemical properties of Mo(VI)o2(5-X-SSP) and Mo(VI)o2(5-X-SSE), (5-X- SSP2- = 2-((5-X-salicylidene)amino)benzenethiolate; 5-X- SSE2- = 2-((5-X-salicylidene)amino)ethanethiolate; X = Br, Cl, H, CH3O), which contain tridentate (ONS) Schiff base ligands is described. The chemical properties of these molybdenum complexes are compared with those which possess tridentate (ONO) Schiff base ligands. Cyclic voltammetry was used to obtain cathodic reduction potentials (EPC) for the quasi-reversible reduction of the cis-dioxomolybdenum (VI) complexes. Although the reductions are quasi-reversible, trends are observed in EPC both within series and when different series are compared. Cathodic reduction potentials for the four series of complexes examined span the range -l.53 to -l.05 V versus NHE.
The oxygen atom transfer reactions for Mo(VI)o2(5-X-SSP) and Mo(VI)o2(5-X-SSE) with PEtPh2 were studied in detail between 30 and 60°C. The applicable rate law is +d[Mo(IV)OL]/dt = k1[Mo- (VI)o2L][PEtPh2]. The specific rate constants span the range from 8.4 x 10 (X = CH3O) to 19.6 x 10-4 M-1S-1 (x = Br) for Mo(VI)o2(5-X-SSP) at 30°C and from 21.4 x 10-4 M-1S-1 (x = CH3O) to 34.8 x 10-4 M-1S-1 (X = Br) for Mo(VI)o2(5-X-SSE) at 60°C. Only oxomolybdenum (IV) complexes are observed as products of these reactions. This is a significant result. A linear dependence is observed between log(k1X/k1H) and the Hammett oP parameter for the ligand x substituents for the two series Mo(VI)o2(5-X-SSP) (p = +0.75) and Mo(VI)o2(5-X-SSE) (p = +0.42). Activation parameter data were obtained for Mo(VI)02(5-H-SSP) (Ea = 67.9 kJ/mol, ΔH+ = 65.2 kJ/mol, ΔS+ = -86.5 J/(mol-K)) and 70.3 kJ/mol, ΔS+ Mo(VI)o2(5-H-SSE) (Ea 72.0 kJ/mol, ΔH+ = -82.6 J/(mol-K)). There are three ligand features whose effect systematically alters both the cis-dioxomolybdenum- (VI) cathodic reduction potentials and specific rate constants. These include (1) the X-substituent on the salicylaldehyde portion of each ligand; (2) the degree of ligand delocalization; and (3) the substitution of a sulfur donor atom for an oxygen donor atom. Each of these effects is considered separately with regard to both the cis-dioxo- molybdenum(VI) cathodic reduction potentials and specific rate constants, then their cumulative effect is discussed. There exists a correlation between the specific rate constants and Epc for Mo(VI)02(5-X-SSP) and Mo(VI)02(5-X- SSE). Initial results are included on the reaction of Mo(IV)02(5-H-SSP) with NO3-. Spectral results suggest conversion of Mo(IV)02(5-H-SSP) to Mo(VI)02(5-H-SSP) by way of an oxygen atom transfer reaction.
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Rae, K. J. "The variation of some bioinorganic parameters in rheumatoid arthritis". Thesis, University of Strathclyde, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.371978.
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Akay, Senol. "Diagnosis and Inhibition Tools in Medicinal Chemistry". Digital Archive @ GSU, 2009. http://digitalarchive.gsu.edu/chemistry_diss/41.
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Cell surface saccharides are involved in a variety of essential biological events. Fluorescent sensors for saccharides can be used for detection, diagnosis, analysis and monitoring of pathological processes. The boronic acid functional group is known to bind strongly and reversibly to compounds with diol groups, which are commonly found on saccharides. Sensors that have been developed for the purpose of saccharide recognition have shown great potential. However, they are very hydrophobic and this lack of essential water-solubility makes them useful in biological applications. The first section of this dissertation details the process of developing water-soluble saccharide sensors that change fluorescent properties upon binding to saccharides. The second section of the dissertation focuses on the development of DNA-minor groove binders as antiparasitical agents. Parasitical diseases comprise some of the world’s largest health problems and yet current medication and treatments for these parasitical diseases are often difficult to administer, costly to the patients, and have disruptive side effects. Worse yet, these parasites are developing drug resistance, thus creating an urgent need for new treatments. Dicationic molecules constitute a class of antimicrobial drug candidates that possess high activity against various parasites. The second section details the development of a series of di-cationic agents that were then screened in in vitro activities against parasitical species.