In the last two decades chemometrics has become an essential tool for the experimental biologist and chemist. The level of contribution varies strongly depending on the type of research performed. Therefore, chemometrics may be used to interpret and explain results, to compare experimental data with real-word ‘unseen’ data, to accurately detect certain chemical vapour, to identify cancerous related metabolites, to identify and rank potentially relevant/important variables or simply just for a pictorial interpretation and understanding of the results. Whilst many chemometrics methods are well-established in the area of chemistry and metabolomics many scientists are still using them with what is often referred to as a ‘black-box’ approach, that is without prior knowledge of the methods and well-recognised statistical properties. This lack of knowledge is thanks to the wide availability of powerful computers and – perhaps more notably – up-to-date, easy to use and reliable software. The main aim of this study is to reduce this gap by providing extensive demonstration of several approaches applied at different stages of the data analysis pipeline highlighting the importance of appropriate method selection. The comparisons are based both on chemical and biochemical (metabolomics) data and construct a firm basis for the researchers in terms of understanding of chemometric methods and the influence of parameter selection. Consequently, in this thesis the exploration and comparison of different approaches employed for various statistical steps are investigated. These include pre-treatment steps such as dealing with missing data and scaling. First, different substitution of missing values and their influence on unsupervised and supervised learning have been compared, where it has been shown that metabolites that display skewness in distribution can have a significant impact on the replacement approach. The scaling approaches were compared in terms of effect on classification accuracy for variety of metabolomics data sets. It was shown that the most standard option which is autoscaling is not always the best. In the next step a comparison of various variable selection methods which are commonly used for the analysis of chemical data has been carried out. The results revealed that random forests, with its variable selection techniques, and support vector machines, combined with recursive feature elimination as a variable selection method, displayed the best results in comparison to other approaches. Moreover, in this study a double cross-validation procedure was applied to minimize the consequence of over-fitting. Finally, seven different algorithms and two model validation procedures based on either 10-fold cross-validation or bootstrapping were investigated in order to allow direct comparison between different classification approaches.

There is currently much interest in the investigation of dynamics in solids and the primary goal of this thesis is to present well-known and new NMR methods used for studying motion on Larmor and spectral timescale. The quadrupolar interaction usually dominates solid-state NMR spectra of quadrupolar nuclei. When the magnitude of quadrupolar interaction is large then the second-order correction to the dominant Zeeman Hamiltonian must be considered. Owing to this second-order quadrupolar effect, NMR peaks can be displaced from their chemical shift positions by a second-order shift. When considering motional averaging of the second-order shift, the critical frequency is the Larmor frequency, 0. In the case of motion that is faster than the Larmor precession, the isotropic quadrupolar shift is affected. This analogous phenomenon in solution-state NMR is known as the "dynamic shift". In Chapter 4, it will be shown that multiple-quantum NMR measurements of isotropic second-order quadrupolar shifts are a simple way to probe nanosecond timescale motions in solids. An analysis of one- and two-dimensional 11B MAS NMR spectra of three isomers of the closo-carboranes gives the results that provide the first evidence for the presence of solid-state dynamic shifts. There are several experiments that provide a sensitive test for the presence of dynamics on spectral timescale. One piece of evidence for dynamics on the spectral timescale is a motional broadening of quadrupolar satellite-transition spinning sidebands. Therefore, it is possible to investigate the influence of dynamic reorientation on satellite-transitions MAS spectra by recording variable-temperature one-dimensional spectra with wide spectral width or by comparing two-dimensional STMAS spectra with MQMAS spectra. These methods can be extended to 2H NMR spectroscopy as the sidebands observed in the magic angle spinning (MAS) NMR spectrum of a spin I = 1 2H nucleus may be very strongly broadened due to interference between the line-narrowing effects of MAS and the dynamics-driven reorientation of the 2H quadrupole tensor, if motion is present in the solid. In the last chapter, the 27Al, 31P and 2H NMR study of AlPO-34 type materials with the topology of chabazite are undertaken and the use of the full range of NMR methods to develop a structure and dynamic behaviour of these materials is presented. In addition, the NMR calculations are performed in order to combine DFT calculations with experimental data. Finally, GaPO-34 samples were investigated to extract information about the effects of Ga substitution in AlPO-34 on dynamical behaviour.

ENDOR spectroscopy and DFT calculations were used for the first time to thoroughly investigate the ligand hyperfine couplings for [Cu(acac)2] in frozen solution. Anisotropic hyperfine couplings to the methine protons (HAi = 1.35, -1.62, -2.12 MHz; aiso = -0.80 MHz) and smaller couplings to the fully averaged methyl group protons (HAi = -0.65, 1.66, -0.90 MHz; aiso = 0.04 MHz) were identified by simulation of the angular selective CW Q-band ENDOR spectra and confirmed by DFT. Variable temperature X-band Mims ENDOR revealed an additional set of hyperfine couplings which showed a pronounced temperature dependency. These additional couplings were characterised by HAi = 3.45, 2.90, 2.62 MHz, aiso = 2.99 MHz and assigned to a sub-set of methyl groups undergoing hindered rotation in frozen solution. From DFT calculations the hindered rotation is proposed to occur in 120° jumps via proton tunnelling. Changes in the spin Hamiltonian parameters (g/CuA) of [Cu(acac)2] upon addition of nitrogen bases evidenced the formation of adducts. Pyridine bases were found to form square pyramidal, mono-axial adducts, labelled [Cu(acac)2(X)], even in a large molar excess of base, whilst both mono-axial [Cu(acac)2Im] and bis-equatorial [Cu(acac)2Im2] adducts were formed by imidazole coordination depending on the molar equivalents of imidazole present in solution. Angular selective 1H ENDOR studies confirmed that the acetylacetonato ligand protons were largely unaltered upon adduct formation. The proton hyperfine tensors for the coordinated substrates were found to be informative on the mode of coordination, confirming the axial coordination of the pyridine bases. Furthermore, discrimination between endocyclic and exocyclic coordination of the 2-aminomethylpyridine bases was achieved. A cis-mixed plane geometry of the [Cu(acac)2Im2] adduct was observed in the 10K ENDOR spectrum and supported by DFT calculations. This was in contrast to the bis-equatorial configuration evident in the 140K EPR, implying a temperature dependant isomerisation. Finally, a series of square planar Casiopeina copper complexes of general formula [Cu(acac)(N-N)], consisting of an acetylacetonato ligand and a diimine ligand (N-N) of varying size, were prepared and characterised by EPR and ENDOR spectroscopy. Angular selective 1H ENDOR spectra revealed the magnitude of the largest imine hyperfine component, observed at g, to be sensitive to size of the diimine ligand. This is thought to be related to the extent of spin delocalisation in the diimine ligand.

Electrospray (ESI-MS) and cryospray mass spectrometry (CSI-MS) techniques were developed to analyse and investigate the self-assembly, reactivity and structure of supramolecular architectures. Using ESI-MS, the complexation reactions of the ligand cis,trans-1,3,5-tris(pyridine-2-carboxaldimino)cyclohexane (ttop) with divalent first row transition metal salts to form complexes with nuclearities 1,2 and 4 were followed. In-situ mass spectrometry was also utilised to show the stepwise formation of the ligand-metal complexes. Mass spectrometry has been used to identify the reactive species in the catalytic oxidation of conventionally hard to activate C-H and C=C moieties. The identity of the reactive species under catalytic conditions has been postulated as Fe(V)=O but direct observation of this species has not been possible before. Using cryospray mass spectrometry, the Fe(V)=O reactive intermediate within the synthetic [FeV(O)(OH)(PyMe2tacn)]+ (PyMe2tacn = 1-(2’-pyridylmethyl)-4,7-dimethyl-1,4,7-triazacyclononane) complex at -40 ºC and its reaction with an olefin was observed. Oxygen atom transfer from H2O2 / H2O was followed through Fe(V)=O to the products with isotopic labelling, and the reactivity was probed as a function of temperature. Mass spectrometry has been used as both a qualitative and quantitative tool to deduce the stoichiometry of an anion receptor and the corresponding anion. Job plots of mass spectrometry data have been compared to the conventional 1H NMR job plot data to give corresponding results therefore providing evidence of the use of mass spectrometry as a quantitative and qualitative analytical tool. Mass spectrometry has been used to follow the formation of heterometallic complexes and provide evidence of their building block in solution. The formation of the complexes has been followed using time-resolved mass spectrometry experiments and the building blocks analysed.

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A series of novel multi-metallic luminescent Au(I) and Re(I) complexes have been synthesised targeting functionality as cellular imaging and/or therapeutic agents. Both the ligands and their complexes have been characterised by a variety of spectroscopic and spectrometric techniques. Several complexes were also characterised by X-ray crystal diffraction and/or elemental analysis. In both chapters two and three the modulation of the luminescent properties of a series of mono- and di-metallic [Re(CO)3(N^N)L]+ type complexes bearing functionalised alkyl chains by hydrophobically driven, intra- and intermolecular conformational changes is reported. Additionally, the first application of di-metallic Re(I) complexes in cellular imaging is reported with specific localisation in the nucleoli or ER and Golgi apparatus. In both chapters four and five the synthesis of novel mono- and di-metallic Au(I) complexes is reported. Several complexes demonstrated cytotoxicity as well as compartemental localisation in cellular imaging demonstrating their potential as dual-functional cellular imaging and/or therapeutic agents. As an extension to the work discussed in Chapters two to five, the synthesis of novel multi-metallic luminescent complexes is reported in Chapter six. For the tri-hetero-metallic complex incorporating Au(I) and Re(I) units, cytotoxicity towards four cancer cell lines and non-specific localization throughout the entire cell is described.

Several viral envelope glycoprotein oligomers assembled into a viral fusion machine, form a molecular scaffold that brings the viral and target cell membranes into close apposition and allow the subsequent fusion events. The fusion pore formation and its sequential expansion are orchestrated by viral and cellular lipids and proteins. The HIV entry process is understood in some detail at the molecular level. It is coordinated by the HIV envelope glycoprotein complex, a trimer of three gp120 surface glycoproteins, each noncovalently attached to three gp41 ransmembrane glycoprotein subunits.%&/It is know that changes in GSLs expression in target membranes can modulate viral fusion and entry. These studies on structure-function relationship of target membrane GSLs, the gp120-gp41 and the viral receptors suggest that plasma membrane GSLs support HIV-1 entry by stabilizing the intermediate steps in the fusion cascade. These observations, led it to hypothesize that upregulation of GSLs metabolites (such as ceramide) and/or modulation of GSLs, which preferentially partition in the plasma membrane microdomains, could have a significant influence on HIV-1 entry. %&/Based on these findings, in this work has been developed a strategy to synthesize glycodentritic polymers that bind HIV rgp120 and inhibit HIV-1 entry. To reach this goal, first it was carried out the total synthesis of D-erytrho-sphingosine with high enantioselectivity and diasteroselectivity. Then, an efficient protocol of glycosylation of ceramides employing stannyl derivatives as strategy was developed. Finally, water-soluble hyperbranched glycodendritic polymers for the study of carbohydrate interactions were synthesized. These glycoconjugate consists of Boltorn H30 hyperbranched polymers, based on the monomer 2,2-bis(hydroxymethyl)propionic acid, functionalized with naturally occurring -Galceramide. The click chemistry permits functional group tolerance during the derivatization of Boltorn H30. Their ability to bind HIV-1 rgp 120 was demonstrated using surface plasmon resonance (SPR). / El proceso de infección por VIH-1 es entendido a nivel molecular como la coordinación de la glicoproteína gp120 del virus con glicoesfingolípidos presentes en las membranas celulares de los organismos infectados. Lo anterior permite plantear la idea de que una regulación en el metabolismo de los glicolípidos presentes en las membranas celulares, pueden influir significativamente en la inhibición de la infección con el VIH-1. A partir de esas observaciones, en el presente trabajo se describe la síntesis de glicopolímeros dendriméricos, los cuales tiene la capacidad de reconocer a la proteína rgp120 del VIH-1 e inhibir la entrada del virus a la célula. La primera meta fue la síntesis asimétrica de D-eritro-esfingosina. Posteriormente se desarrolló un protocolo eficiente para la glicosilación de ceramidas. Finalmente, dos glicopolímeros hiper-ramificados, solubles en agua, fueron sintetizados para estudiar las interacciones proteínas-carbohidrato. La estructura de dicho polímero fue el Boltorn H30, unido con una -galceramida.

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