Made available in DSpace on 2014-06-11T19:35:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-09Bitstream added on 2014-06-13T18:46:23Z : No. of bitstreams: 1 moro_ac_dr_araiq.pdf: 1966130 bytes, checksum: f48d30b6891d8f96c24dc4f6f5cdf2b2 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Os ciclopaladados do tipo [Pd(dmba)(X)L] e [Pd2(dmba)2(μ-L)] (Hdmba = N,N-dimetilbenzilamina; X = haletos ou pseudo-haletos; L = ligantes mono ou bidentados) são compostos estáveis ao ar e empregados em vários estudos biológicos devido a seus potenciais antitumorais. Este trabalho contempla a síntese e caracterização estrutural dos ciclopaladados mononucleares [Pd(dmba)(X)tu] (tu = tiouréia; X = Br (8), I (9)), binucleares [Pd2(dmba)2(X)2(μ-bpp)] (bpp = 1,3-bis(4-piridil)propano; X = Cl (10), Br (11), NCO (12), N3 (13)), e poliméricos [{Pd(dmba)}2{μ-Fe(CN)5NO}]n (14), [{Pd(dmba)}2{μ-Pd(CN)4}]n (15), bem como das espécies [Pd2(Cl)4(PPh3)2(μ-ted)] (16), [Pd2(Br)2(Cl)2(PPh3)2(μ-ted)] (17) e [Pd2(N3)4(PPh3)2(μ-ted)] (18) (PPh3 = trifenilfosfina; ted = trietilenodiamina). As estruturas foram propostas com base em medidas de análise elementar, espectroscopia vibracional na região do infravermelho e espectroscopia de ressonância magnética nuclear. As estruturas de [Pd(dmba)(μ-Br)]2 (4), [Pd(dmba)(Br)tu] (8) e [Pd2(N3)4(PPh3)2(μ-ted)] (18) foram determinadas via difração de raios X por monocristal. Este estudo evidenciou também que as ligações hidrogênio são importantes para direcionar a auto-associação das espécies 8 e 18 durante a cristalização. O comportamento térmico dos compostos 10-12, 14-17 foi investigado por termogravimetria e análise térmica diferencial e os resíduos caracterizados por difração de raios X, método do pó. Além destes, foram sintetizadas as espécies conhecidas [Pd(dmba)(Cl)tu] (6) e [Pd(dmba)(N3)tu] (7), com o intuito de investigar suas atividades biológicas e compará-las com as de outras espécies que apresentam os mesmos ligantes (dmba e tu). As citotoxicidades in vitro dos ciclopaladados e da cisplatina... / Cyclopalladated complexes of the type [Pd(dmba)(X)L] and [Pd2(dmba)2(μ-L)] (Hdmba = N,N-dimethylbenzylamine; X = halides or pseudohalides; L = monodentate or bidentate ligands) are air stable compounds and nowadays employed in several biological studies because of their potential antitumour activities. This research deals with the synthesis and structural characterization of the mononuclear cyclopalladated compounds [Pd(dmba)(X)tu] (tu = thiourea; X = Br (8), I (9)), dinuclear [Pd2(dmba)2(X)2(μ-bpp)] (bpp = 1,3-bis(4-pyridyl)propane); X = Cl (10), Br (11), NCO (12), N3 (13)), and polymers [{Pd(dmba)}2{μ-Fe(CN)5NO}]n (14), [{Pd(dmba)}2{μ-Pd(CN)4}]n (15), as well of the species [Pd2(Cl)4(PPh3)2(μ-ted)] (16), [Pd2(Br)2(Cl)2(PPh3)2(μ-ted)] (17) and [Pd2(N3)4(PPh3)2(μ-ted)] (18) (PPh3 = triphenylphosphine; ted = triethylenediamine). The compounds structures were proposed on the basis of elemental analysis, infrared vibrational spectroscopy and nuclear magnetic resonance spectroscopy. The crystal and molecular structures of [Pd(dmba)(μ-Br)]2 (4), [Pd(dmba)(Br)tu] (8) and [Pd2(N3)4(PPh3)2(μ-ted)] (18) were determined by single-crystal X-ray diffraction measurements. This study also showed that the hydrogen bonds play an important role for directing self-assembly of 8 and 18 species during the crystallization. The thermal behavior of the compounds 10-12, 14-17 was studied by thermogravimetry and differential thermal analysis and the final decomposition products were identified by X-ray powder diffraction. In addition to these compounds, the known ones [Pd(dmba)(Cl)tu] (6) and [Pd(dmba)(N3)tu] (7) were prepared in order to have their biological activities studied and compared with other ones containing the same ligands (dmba and tu). In vitro cytotoxicity assays of cyclopalladated complexes and cisplatin (standard antitumour drug) were carried... (Complete abstract click electronic access below)

Made available in DSpace on 2014-06-11T19:29:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-02-16Bitstream added on 2014-06-13T19:38:02Z : No. of bitstreams: 1 fernandes_rj_me_araiq.pdf: 2025143 bytes, checksum: 148bce40eac5904bbce48967165adccb (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Este trabalho contempla a síntese e caracterização espectroscópica, estrutural, morfológica e térmica de novos polímeros de coordenação de níquel(II) contendo espaçadores nitrogenados lineares (4-aminopiridina, pirazina, trans-1,2- bis(4-piridil)etileno) e os ânions dicarboxílicos oxalato e malonato. A ideia consiste na preparação de sólidos de coordenação que apresentem simultaneamente porosidade e propriedades magnéticas. Em uma segunda etapa, o estudo foi estendido para outros centros metálicos bivalentes, paramagnéticos, e de geometria preferencialmente octaédrica (manganês, cobalto, cobre). A parte final do trabalho contemplou a investigação do comportamento magnético dos sólidos de níquel(II) obtidos e, também dos sistemas MT/mal/4-apy (MT = Mn, Co, Ni, Cu), através de medidas de susceptibilidade magnética a baixa temperatura, realizadas pelo grupo do Prof. Dr. Rafael Sá de Freitas do Instituto de Física da USP-SP / This work describes the synthesis and spectroscopic, structural, morphological and thermal characterization of new coordination polymers of nickel (II) containing nitrogen linear spacers (4-aminopyridine, pyrazine, trans-1,2-bis (4-pyridyl) ethylene) and the dicarboxylic anions oxalate and malonate. The main goal consists in the preparation of coordination solids exhibiting both porosity and magnetic properties. In a second step, the study was extended to other divalent paramagnetic metal centers, with preferably octahedral geometries (manganese, cobalt, copper). The final part of the work included the investigation of the magnetic behavior of the obtained nickel(II) solids and also of the MT/mal/4-apy systems (TM = Mn, Co, Ni, Cu) through the magnetic susceptibility measurements low temperature, performed by the group of the Prof. Dr. Rafael Sá de Freitas of the Institute of Physics, USP-SP

Thesis (MTech (Chemistry))--Cape Peninsula University of Technology, 2017. / Crystal engineering involves the manipulation of intermolecular interactions to design functionalised crystalline materials and has proved to be an effective tool for the modification of physicochemical properties of active pharmaceutical ingredients (APIs). In the first section of this study, the aim was to systematically influence the rate of dissolution of a highly soluble active pharmaceutical ingredient using crystal engineering principles. Salicylic acid (SA) was employed as a model API to form multicomponent crystals with a series of selected cinchona alkaloids, namely quinine (QUIN), quinidine (QUID), cinchonine (CINC), cinchonidine (CIND), N-benzylquininium chloride (NBQUIN), N-benzylcinchonidinium chloride (NBCIND) and N-benzylcinchoninium chloride (NBCINC). The resulting novel crystalline forms were found to be salts, and were characterised using single crystal X-ray diffraction, powder X-ray diffraction, differential scanning calorimetry and thermogravimetric analysis. The dissolution profiles of the salicylate salts, measured from an aqueous media using high performance liquid chromatography-mass spectroscopy, show a significant decrease in the rate of dissolution of SA. Subsequently, Hirshfeld surface analysis was used as a tool for quantitative and qualitative comparison of the crystal structures. This study indicates that the rate of dissolution can be successfully influenced by methodically adding extra hydrophobic groups onto the coformer. In the second section, we applied the information obtained from the SA studies to acetylsalicylic acid (aspirin, ASA). We sought to improve its thermal stability and dissolution via the formation of new solid forms with the aforementioned cinchona alkaloids. We successfully synthesized a novel drug-drug salt of an analgesic, non-steroidal antiinflammatory and antipyretic drug (ASA), and an antimalarial and analgesic drug (QUIN). The salt was formed both by using solution methods and liquid assisted grinding - a green chemistry technique. The salt exhibited physicochemical properties different from the parent drugs, and a reduced rate of dissolution. / National Research Foundation(NRF)

Orientador: Antonio Eduardo Mauro / Coorientador: Adelino Vieira de Godoy Netto / Banca: Gilbert Bannach / Banca: Douglas Wagner Franco / Banca: Roberto Santana da Silva / Banca: Victor Marcelo Deflon / Resumo: Os ciclopaladados do tipo [Pd(dmba)(X)L] e [Pd2(dmba)2(μ-L)] (Hdmba = N,N-dimetilbenzilamina; X = haletos ou pseudo-haletos; L = ligantes mono ou bidentados) são compostos estáveis ao ar e empregados em vários estudos biológicos devido a seus potenciais antitumorais. Este trabalho contempla a síntese e caracterização estrutural dos ciclopaladados mononucleares [Pd(dmba)(X)tu] (tu = tiouréia; X = Br (8), I (9)), binucleares [Pd2(dmba)2(X)2(μ-bpp)] (bpp = 1,3-bis(4-piridil)propano; X = Cl (10), Br (11), NCO (12), N3 (13)), e poliméricos [{Pd(dmba)}2{μ-Fe(CN)5NO}]n (14), [{Pd(dmba)}2{μ-Pd(CN)4}]n (15), bem como das espécies [Pd2(Cl)4(PPh3)2(μ-ted)] (16), [Pd2(Br)2(Cl)2(PPh3)2(μ-ted)] (17) e [Pd2(N3)4(PPh3)2(μ-ted)] (18) (PPh3 = trifenilfosfina; ted = trietilenodiamina). As estruturas foram propostas com base em medidas de análise elementar, espectroscopia vibracional na região do infravermelho e espectroscopia de ressonância magnética nuclear. As estruturas de [Pd(dmba)(μ-Br)]2 (4), [Pd(dmba)(Br)tu] (8) e [Pd2(N3)4(PPh3)2(μ-ted)] (18) foram determinadas via difração de raios X por monocristal. Este estudo evidenciou também que as ligações hidrogênio são importantes para direcionar a auto-associação das espécies 8 e 18 durante a cristalização. O comportamento térmico dos compostos 10-12, 14-17 foi investigado por termogravimetria e análise térmica diferencial e os resíduos caracterizados por difração de raios X, método do pó. Além destes, foram sintetizadas as espécies conhecidas [Pd(dmba)(Cl)tu] (6) e [Pd(dmba)(N3)tu] (7), com o intuito de investigar suas atividades biológicas e compará-las com as de outras espécies que apresentam os mesmos ligantes (dmba e tu). As citotoxicidades in vitro dos ciclopaladados e da cisplatina... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Cyclopalladated complexes of the type [Pd(dmba)(X)L] and [Pd2(dmba)2(μ-L)] (Hdmba = N,N-dimethylbenzylamine; X = halides or pseudohalides; L = monodentate or bidentate ligands) are air stable compounds and nowadays employed in several biological studies because of their potential antitumour activities. This research deals with the synthesis and structural characterization of the mononuclear cyclopalladated compounds [Pd(dmba)(X)tu] (tu = thiourea; X = Br (8), I (9)), dinuclear [Pd2(dmba)2(X)2(μ-bpp)] (bpp = 1,3-bis(4-pyridyl)propane); X = Cl (10), Br (11), NCO (12), N3 (13)), and polymers [{Pd(dmba)}2{μ-Fe(CN)5NO}]n (14), [{Pd(dmba)}2{μ-Pd(CN)4}]n (15), as well of the species [Pd2(Cl)4(PPh3)2(μ-ted)] (16), [Pd2(Br)2(Cl)2(PPh3)2(μ-ted)] (17) and [Pd2(N3)4(PPh3)2(μ-ted)] (18) (PPh3 = triphenylphosphine; ted = triethylenediamine). The compounds structures were proposed on the basis of elemental analysis, infrared vibrational spectroscopy and nuclear magnetic resonance spectroscopy. The crystal and molecular structures of [Pd(dmba)(μ-Br)]2 (4), [Pd(dmba)(Br)tu] (8) and [Pd2(N3)4(PPh3)2(μ-ted)] (18) were determined by single-crystal X-ray diffraction measurements. This study also showed that the hydrogen bonds play an important role for directing self-assembly of 8 and 18 species during the crystallization. The thermal behavior of the compounds 10-12, 14-17 was studied by thermogravimetry and differential thermal analysis and the final decomposition products were identified by X-ray powder diffraction. In addition to these compounds, the known ones [Pd(dmba)(Cl)tu] (6) and [Pd(dmba)(N3)tu] (7) were prepared in order to have their biological activities studied and compared with other ones containing the same ligands (dmba and tu). In vitro cytotoxicity assays of cyclopalladated complexes and cisplatin (standard antitumour drug) were carried... (Complete abstract click electronic access below) / Doutor

This thesis describes the synthesis of interlocked anion host systems which exploit hydrogen bonding, halogen bonding, and lanthanide-coordination for anion recognition and sensing in aqueous solution. Chapter 1 introduces the field of anion supramolecular chemistry, with particular focus on areas of particular relevance to this thesis, namely anion recognition and sensing, anion templation and the synthesis of interlocked structures. Chapter 2 describes the synthesis of hydrogen bonding rotaxane and catenane hosts for recognising and sensing oxoanions in aqueous solvent media. The novel use of nitrate anion templation for the synthesis of interlocked molecules is reported, and the unprecedented selective recognition of nitrate in aqueous solvent media is demonstrated. Chapter 3 details the preparation of water soluble permethylated β-cyclodextrin-stoppered rotaxane hosts that utilise halogen bonding and hydrogen bonding interactions to bind anions in pure water. The first thermodynamic investigation into halogen bonding in water is reported, and the relative capabilities of halogen and hydrogen bonding for anion recognition in water are compared. Chapter 4 investigates the incorporation of lanthanide cations into rotaxane hosts for optical anion sensing. The seminal use of lanthanide cation templation for interlocked molecule synthesis is described, before anion templation approaches towards the synthesis of lanthanide-based rotaxanes are discussed. The luminescence anion sensing capabilities of these interlocked hosts are investigated. Chapter 5 describes the experimental procedures used in this work, and details the characterisation of compounds presented in Chapters 2–4. Chapter 6 summarises the conclusions of this thesis.

Fully conjugated porphyrin nanorings combine an end-free π-system with well defined size and shape. They provide models for testing our understanding of light harvesting in natural photosynthetic systems, and may lead to the creation of new functional materials. This thesis describes the template-directed synthesis of novel 10, 16, 18, 20, 24, 30, 40 and 50-porphyrin nanorings using small templates, as well as the investigation of their structure, electronic properties and supramolecular chemistry in solution and on surfaces. This work illustrates the scope of Vernier templating as a tool for the synthesis of monodisperse molecules of unprecedented sizes. Chapter 1 introduces key properties of porphyrins and π-conjugated linear and cyclic porphyrin oligomers and describes the principle methods of preparing non-conjugated and conjugated cyclic polymers. It also covers recent advances in the synthesis of fully-conjugated porphyrin nanorings, in particular Vernier templating. Chapter 2 discusses the formation of higher order porphyrin nanorings (18- and 24-porphyrin nanorings) in the classical synthesis of 6-porphyrin nanoring and the Vernier-templated synthesis of 12-porphyrin nanoring. Chapter 3 describes the Vernier-templated synthesis of 24-porphyrin nanoring and its characterization. Chapter 4 shows that the flexibility of 24-porphyrin nanoring can be locked by the formation of a “sandwich” complex in the presence of a bidentate ligand or by solvent-induced formation of aggregates. Chapter 5 demonstrates the use of templates to control the cyclooligomerization of linear porphyrin oligomers. Vernier-templated synthetic routes to 10-, 30- and 40-porphyrin nanorings are investigated. Chapter 6 reports the electronic properties of porphyrin nanorings as probed by electrochemistry (for 6 porphyrin nanoring) or fluorescence anisotropy measurements (for 24 porphyrin nanoring). Crystal structures of 6 and 12 porphyrin nanoring template complexes are presented. Chapter 7 contains experimental procedures and characterization data of known and novel compounds synthesized in the course of this thesis.

Doctor of Philosophy / Department of Chemistry / Christer B. Aakeroy / The directed-assembly of small molecular building-blocks into discrete supermolecules or extended networks through non-covalent intermolecular interactions is an on-going challenge in the field of crystal engineering. This synthetic challenge may be overcome by identifying or establishing a hierarchy of intermolecular interactions which, in turn, may facilitate a modular supramolecular assembly process producing final products in high yields. A family of three 3-pyridine/amino-pyrimidine supramolecular reactants (SR’s) was prepared and allowed to react with aromatic carboxylic acids producing nine 1:1 molecular co-crystals and four 1:1 ionic salts through heteromeric O-H···N/N-H···O or charge-assisted N–H+···O-/N–H···O- hydrogen bonds with the amino-pyrimidine binding site. We introduced a Q-value, based on AM1 calculations, to show that the amino-pyrimidine moiety is a superior hydrogen-bond acceptor for an incoming carboxylic acid. The amino-pyrimidine/carboxylic acid synthon resulted 13/13 times (100 % yield) even in the presence of other potentially disruptive intermolecular interactions. However, reacting a 4-pyridine/amino-pyrimidine SR and a carboxylic acid in a 1:2 ratio, resulted in structures containing both acid/amino-pyrimidine and acid/pyridine synthons. The same family of pyridine/amino-pyrimidine SR’s were allowed to react with halogentated benzoic acids in which the amino-pyrimidine/carboxylic acid synthon formed 7/7 times (100 % yield) and halogen bonds (N···I or N···Br) extended the SR/acid dimers into polymeric networks 4/7 times (57 %). These results were rationalized through a hierarchial view of intermolecular interactions consisting of hydrogen and halogen bonds. Four bifunctional 3-pyridine/amino-pyrimidine or amino-pyridine SR’s were reacted with neutral metal complexes producing thirteen crystal structures in which the pyridyl moiety coordinates to the metal center 13/13 times (100 % yield) and amino-pyrimidine···amino-pyrimidine hydrogen bonds link the neighboring metal-ligand complexes 10/13 times (77 % yield) into 1-D or 2-D extended architectures. Finally, we synthesized and characterized a series of tetra-substituted hydrogen bond donor and acceptor functionalized, i.e. pyridyl, amino-pyridine, carboxylic acid, resorcinarene-based cavitands forming deep-walled cavitands through amino-pyridine···carboxylic acid heteromeric synthons and a heterodimeric molecular capsule through pyridyl···carboxylic acid hydrogen bonds. The heterodimeric capsule is only one of three, of its type, characterized crystallographically.

Currently, there is interest in the development of molecular-scale devices for use in quantum information processing (QIP). With this application in mind, physical studies on antiferromagnetically coupled molecular wheels [Cr7MF3(Etglu)(O2CtBu)15(phpy)], where M is a divalent metal cation (M = Mn2+, Zn2+, Ni2+) have been pursued. The heterometallic wheels contain an octagon of metal centres, which are bridged by fluoride ions, pivalate groups and a chiral N-ethyl-D-glutamine molecule which is penta-deprotonated and bound to the metal sites through all available O-donors. They are deep purple in colour and they have been named purple-Cr7M. There is antiferromagnetic coupling between adjacent metal centres, J » -8 cm-1, resulting in a non-zero net spin ground state. The spin-Hamiltonian parameters of this family have been determined.At the heterometal site of purple-Cr7M wheels there is a terminal ligand which can be substituted for a variety of N-donor organic ligands. A series of bidentate N-donor linkers has been used to link Cr7Ni wheels (each wheel Seff = 1/2) to create prototype two-qubit systems. Multi-frequency EPR spectroscopy and SQUID magnetometry has been used to extract the spin-Hamiltonian parameters of this family. It has been shown that the single wheels can be linked together electronically as well as chemically. It has been found that for the unsaturated linkers, there is a weaker interaction between Cr7Ni wheels when longer linkers are used. The strength of interaction is smaller for the saturated linkers than for the unsaturated linkers.The formation of 'green'-Cr7M wheels is different, being templated around a cation. Two new types of wheels have been studied: [tBuCONHC6H12NH2C6H12NHCOtBu][Cr7M2+F8(O2CtBu)16] and [Cs?Cr7MF8(O2CtBu)16]·0.5MeCN (where, M = Mn2+, Zn2+, Ni2+), where the former is templated around a long dialkylammonium group and the latter around a caesium cation. The effect of the templating cation on spectroscopic properties has been determined.Physical studies on a family of antiferromagnetically-coupled homometallic clusters have been pursued. They consist of cyclic arrays of homometallic Cr3+ ions in either a octametallic wheel or hexametallic horseshoes. The horseshoes have the general formula: [CrxFx+5L2x-2]n3- (where L = carboxylate). Cr3+ centres are bridged by pivalate groups and fluorides, while Cr3+ centres at the ends of the chain have terminal fluorides completing their coordination sphere. These terminal fluoride groups are labile enough to be substituted, e.g. [EtNH2][Cr6F7(O2CtBu)10(acac)2] is the product of a substitution reaction with acetylacetone.

Dynamic combinatorial chemistry (DCC) is a powerful method for synthesising complex molecules and identifying unexpected receptors. Chapter 1 gives an overview of the concept of DCC and its applications, and discusses its evolution to date. Chapter 2 describes the discovery of a new generation of donor-acceptor [2]catenanes in aqueous dynamic combinatorial systems. The assembly of these [2]catenanes is promoted by a high salt concentration (1 M NaNO3), which raises the ionic strength and encourages hydrophobic association. More importantly, a mechanism that explains and predicts the structures formed is proposed, giving a fundamental insight into the role played by hydrophobic effect and donor-acceptor interactions in this process. Building on these results, Chapter 3 describes the assembly in high salt aqueous libraries of a larger structure: a [3]catenane. Remarkably, the [3]catenane exhibits strong binding interactions with a biologically relevant target - spermine - in water under near-physiological conditions. Its synthesis is improved if the salt is replaced by a sub-mM concentration of spermine, acting as a template. Chapter 4 explores in further detail how subtle variations in the building block design influence the selective formation of either [2] or [3]catenanes. This last section underlines both the advantages and the limitations of the method developed in Chapter 3. After a short conclusion (Chapter 5), Chapter 6 gives experimental details.

No description available.