In recent years the microelectronics industry as found itself at an impasse. The tradition pathway towards smaller transistors at lower costs has hit a roadblock with the failure of 157 nm lithography and the continued delays in 13.5 nm extreme ultra violet light sources. While photolithography has been able to keep pace with Moore’s law over the past four decades, alternative patterning technologies are now required to keep up with market demand. The first section of this dissertation discusses the new resolution enhancement technique develop in the Willson lab termed pitchdivision. Through the incorporation of specifically tailored photobase generators (PBGs) into commercially available resists, the resolution of current 193 tools may be doubled. Special two-stage PBGs were designed and synthesized to increase the image fidelity of pitchdivision patterns. The next project deals with the design, synthesis, and evaluation of resists that find amplification through unzipping polymers. An aromatizing polyester polymer that acts as dissolution inhibitor in novolac and is inherently sensitive to 13.5 nm exposure is discussed. Initial results show excellent sensitivity and promise towards a new class of EUV resists. / text

Damage to primary photosynthetic reactions caused by environmental stress can be assessed by measurement of chlorophyll fluorescence induction in intact leaves. This approach was applied in studies of ultraviolet-B photoinhibition of photosynthesis in Pisum sativum L. and Rumex patientia L. leaves. At ultraviolet-B dose rates insufficient to cause inhibition of net photosynthesis, changes in the magnitude of fluorescence transients did occur, which suggested direct effects on chloroplast pigments in Pisum and inhibition of photosynthetic electron transport between the photosystems in both species. Leaves of these two species subjected to a much higher dose rate had a significant reduction of net photosynthesis and changes in the magnitude of fluorescence transients that indicated partial loss of water-splitting capability and direct effects on chloroplast pigments. Ultraviolet radiation-induced changes of photosynthetic thylakoid membranes may be ultimately responsible for these disruptions of the primary photosynthetic reactions.

The requirements of information storage exclusively continue to increase in our daily lives and future, will need even more memory space which should be very small in size but hold the capacity to store a huge volume of information. For that reason, modern research is focusing on molecular memory or optical switches devices where nanoparticles undergoing light-induced transformations (e.g. photodimerization) between structural phases with different optical properties are key components. Hence, the UV reversible photodimerization of the cinnamate groups have the potential to be used as switching segments in optical memory devices. The dissertation deals with the solid state NMR investigation on the influence of alkali cations on the photodimerization of cinnamate salts and cinnamic acid derivatives intercalated in hydrotalcite LDH (layered double hydroxides). The packing of molecules determines reactivity and stereo product, so the motivation is to modify molecular packing through noncovalent interactions by using different cations to influence packing and photodimerization products as well as photodimerization kinetics. The alkali metal salts of m-bromo/chloro cinnamic acid and their photodimerization products are analyzed by solid-state NMR. Cesium, rubidium, and potassium salts show well resolved signals in the 13C CPMAS spectra, whereas for ammonium and sodium salts broader lines are obtained. The size of the cation and with that the packing arrangement in the crystal has a significant influence on the resulting spectra. Cesium, rubidium, and potassium salts photoreact to the corresponding truxinates with a non-planar cyclobutane ring but disorder and lower crystallinity are found in the ammonium and sodium photoproducts. In case of divalent cations, both show good crystal packing in the reactant but Ca di-trans cinnamate shows better photoreaction than Mg di-trans cinnamate. Analysis of the kinetics by the Johnson-Mehl-Avrami-Kolmogorov (JMAK) equation shows that the reaction rate is faster with smaller catcationsd in general chlorine salts react faster than the corresponding bromine salts. Furthermore, dethe termination of the chemical shift anisotropy (CSA) tensor for reactant and product provides information for required atomic reorientations in consequence of photoreaction. Results are explained based on these necessary movements of atoms betweethe n reactant and product. Finally, m-bromo cinnamate and K m-bromo cinnamate are successfully incorporated into the LDH to investigate photoreactivity in a confine system. These samples also undergo [2+2] photodimerization upon irradiation with UV light to yield truxinates the , but high degree of disorder in the ipso, cyclobutane and carboxylate spectral region of the photoproduct is found which indicates low crystallinity in both samples.:Bibliographische Beschreibung III Table of contents V List of Figures VII List of Tables XIX Abbreviations XXI 1 Motivation 1 2 Introduction 4 2.1 [2+2] photodimerization of cinnamic acid 5 2.2 Cinnamic acid as optical memory or molecular switches 7 2.3 Layered Double Hydroxide (LDH) 9 2.4 Previous studies of cinnamic acid derivatives by SSNMR 10 3 Experimental 12 3.1 NMR techniques 12 3.1.1 NMR interactions in Solid State NMR 12 3.1.2 Chemical Shift: 13 3.1.3 Dipole-Dipole Interaction: 13 3.1.4 Magic-angle spinning (MAS) 14 3.1.5 Relaxation times 15 3.2 Pulse sequences 16 3.2.1 13C CP (Cross polarization) 16 3.2.2 Dipolar decoupling 17 3.2.3 13C cross polarization dephasing experiment 17 3.2.4 Dipolar coupling 18 3.2.5 2D PASS 19 3.2.6 FSLG 13C-1H CP HETCOR 20 3.3 Typical measurement parameters 20 3.4 Sample preparation 22 3.4.1 Preparation of different cinnamate salt 22 3.4.2 Incorporation of cinnamic compounds into LDH 24 3.5 Sample irradiation by an UV lamp 24 3.6 Computational methods 28 3.7 Single crystal structure data 28 4 Results and discussion 30 4.1 m-Br cinnamate salts of different cations 30 13C CPMAS Spectra of Truxinates 42 Summary 57 4.2 m-Cl cinnamate salts of different cations 57 13C CPMAS Spectra of Truxinates 69 Summary 83 4.3 Influence of divalent cation on cinnamic acid 84 Ca di-trans-cinnamate 84 Mg di-trans-cinnamate 91 Summary 95 4.4 Photoreaction kinetics of cinnamate salts 96 Analysis of reaction kinetics 96 Summary 119 4.5 Intercalation of cinnamic acid derivatives in LDH 120 5 Conclusion 131 6 Outlook 135 7 Appendix 136 8 References 146

La molécule UM171 amplifie les greffons de cellules souches hématopoïétiques. Cela permet l’utilisation de greffons de cellules souches provenant du sang de cordon ombilical pour des greffes chez les patients adultes, notamment dans les cas de cancers du sang. Bien que le mode d’action biologique d’UM171 soit connu, la protéine à laquelle se lie UM171 reste indéterminée. Le but de ce projet est d’identifier cette protéine-cible. Afin d’atteindre cet objectif, cette étude mise sur la conception, la synthèse, puis l’utilisation de sondes d’affinité. Dans ce mémoire, deux types de sonde sont présentées : les sondes d’affinité non covalentes et les sondes d’affinité photoréactives. Dans un premier temps, une sonde non covalente est synthétisée. Cette sonde, très active, est ensuite utilisée dans un essai de chimio-protéomique. Elle permet d’identifier les protéines KBTBD4, RCOR1 et HDAC2 par buvardage de western. Dans un deuxième temps, une sonde photoréactive est conçue, puis synthétisée. Considérant l’hypothèse de la présence d’un acide carboxylique dans le site actif de la protéine-cible, cette sonde exploite une fonctionnalité 2,5-diaryltétrazole comme groupement photoréactif sélectif aux acides carboxyliques. Afin de maximiser l’activité de cette sonde, celle-ci est développée grâce à l’étude de plusieurs analogues, dont la synthèse est également rapportée. Dans un troisième temps, la sonde photoréactive est utilisée dans deux essais de chimio- protéomique. Ces essais ont permis d’identifier la protéine CUL3 par spectrométrie de masse. La protéine CAND1 a également été identifiée, de façon moins significative. / The small molecule UM171 amplifies hematopoietic stem cells grafts. This allows the use of umbilical cord blood stem cells grafts for transplants in adult patients, for example in the case of blood cancer. Although the biological mode of action of UM171 is known, the protein to which UM171 binds remains undetermined. The aim of this project is to identify this target protein. To achieve this goal, this study focuses on the design, synthesis, and use of affinity probes. In this thesis, two types of probes are presented: non-covalent affinity probes and photoreactive affinity probes. First, a non-covalent probe is synthesized. This probe revealed to be very potent and is used in a chemoproteomics assay. The proteins KBTBD4, RCOR1 and HDAC2 are identified by western blotting. Second, a photoreactive probe is designed, and then synthesized. Assuming the presence of a carboxylic acid in the active site of the target protein, this probe exploits a 2,5-diaryltetrazole functionality as its photoreactive group selective to carboxylic acids. To maximize the activity of this probe, it is designed by studying several analogues, the synthesis of which is also reported. Third, the photoreactive probe is used in two chemoproteomics assays. These led to the identification of the protein CUL3 by mass spectrometry. The protein CAND1 was also identified, less significantly.

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The kinetics of drugs photodegradation have traditionally been treated using thermal kinetic analysis methods consisting most commonly in zero and first order kinetics. These treatment strategies were shown to lack specificity and present a number of limitations when applied to photoreactions kinetics. Nevertheless, these methods have widely been used due to a lack of integrated rate-laws for the majority of photoreactions types, in turn, due to the presence of a variable time-dependent factor in most photoreactions rate-laws that prevents their mathematical integration. To address these limitations, a new methodology for the development and validation of semi-empirical integrated rate-laws that faithfully describe photoreactions kinetics and photoreactions simulated cases generated by numerical integration methods (NIMs), is hereby presented. Using this methodology, a new kinetic order was ascribed to photoreactions namely the Φ-order kinetics. Semi-empirical integrated rate-laws were, thus, developed for three photoreaction types namely, unimolecular, AB(1Φ), photoreversible ,AB(2Φ), and consecutive, AB4(4Φ), photoreactions. The proposed models were further tested experimentally on drugs following these photodegradation mechanisms using; nifedipine and nisoldipine for unimolecular photoreactions; montelukast and fluvoxamine for photoreversible reactions; and riboflavin for consecutive photoreactions. The developed models not only accurately described the photoreaction kinetics of these drugs but also allowed the determination of all the kinetic parameters that characterise them. Furthermore, the above studied drugs were shown to act as precise and simple actinometers when analytically treated with the Φ-order kinetic methods, hereby presented. A universal standard method for the precise and worldwide reproducible study of drugs stability and compounds photoreactions, based on monochromatic irradiation and Φ-kinetics data analysis, is also detailed and adopted throughout the thesis. Finally, two new kinetic parameters namely, the pseudo-rate-constant and pseudo-initial velocity have been identified and shown to be more reliable and accurate in the description and universal comparison of photoreactions kinetics.