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In this master’s thesis, linear zwitterionic poly(ethylene imine) methyl-carboxylates (l-PEI-MCs) were synthesized through a four-step synthesis. The synthesis started with the polymerization of 2-ethyl-2-oxazoline (EtOx) monomers into poly(2-ethyl-2-oxazoline) (PEtOx) homopolymers with polymerization degree of 50 and 100. Living cationic ring-opening polymerization (LCROP) enabled a good control over the molecular weights. Subsequently, the side chains of PEtOxs were cleaved off by acidic hydrolysis. This resulted in linear poly(ethylene imine)s (l-PEIs) bearing a secondary amine group in repeating units of the polymer chain. These amine units were then functionalized with methyl-carboxylate moieties by first introducing tert-butyl ester functionalities to l-PEI chains, and subsequently cleaving off the tert-butyl groups. The final polymer is a polyzwitterion, featuring both an anionic carboxylate and a cationic tertiary amine group within a single repeating unit. Polymers produced in each step were characterized via 1H-NMR and FT-IR spectroscopy and their thermal properties were analyzed by differential scanning calorimetry (DSC). The molecular weights and dispersities (Ð) of PEtOx polymers were additionally estimated by gel permeation chromatography (GPC). Via 1H-NMR, the degree of polymerization for PEtOxs and the hydrolysis degree for l-PEIs were determined. FT-IR gave a further insight into the structures of polymers, successfully confirming the ester functionality of modified l-PEI. The disappearance of the tert-butyl proton signal in 1H-NMR spectrum after deprotection verified the successful removal of tert-butyl groups, resulting in the final product with methyl-carboxylate functionalities. By DSC, different thermal transitions, i.e., glass transition (Tg), melting (Tm) and crystallization (Tc), were observed, and the effects of molar mass and polymer modifications on these transitions were being investigated. The state of the art explores the literature regarding synthesis and properties of poly(2-oxazoline)s (POx), poly(ethylene imine)s (PEIs), and polyzwitterions. The theory behind living cationic ring-opening polymerization of 2-oxazolines and acidic hydrolysis of POxs is described. Different post-polymerization modification strategies to functionalize PEIs are being discussed. In addition, possible applications for each of these polymer classes are shortly outlined.

Prostate cancer is the most common cancer in male population in the western world. In Finland around 5000 men are diagnosed with it every year. Most patients are diagnosed with localized prostate cancer, when the prognosis is good: the relative 5-year survival is over 90%. The metastasized form of prostate cancer can be considered fatal, since the 5-year survival rate for patients with metastases in distant organs is about 29%. Early diagnosis and clear and definite understanding of patient's tumor profile are fundamental parts of optimized treatment of prostate cancer. Proliferation and antiapoptotic characteristics of prostate cancer tissue is caused by altered androgen receptor signaling. Many treatment forms of prostate cancer are concentrating on inhibiting this signaling pathway. Furthermore expression of androgen receptors is increased in prostate cancer tissue compared to healthy tissue. These factors corroborate that androgen receptor is a good candidate for targeting and imaging prostate cancer. With positron emission tomography tracers it is possible to quantitatively detect receptors in vivo. Selective androgen receptor modulators are class of drug molecules that alter androgen receptor activity. They have high affinity to androgen receptor. The aim of this master's thesis was to produce a fluorine-18 and/or iodine-131 labelled selective androgen receptor modulator derivative that could be used for imaging androgen receptor lesions in metastatic prostate cancer. Two different selective androgen receptor modulators were investigated. The second one, a 4-(pyrrolidin-1-yl) benzonitrile derivative was labelled successfully with iodine-131. Its binding to androgen receptor was tentatively shown with LnCapAR cell line. The radiolabelled compound showed binding to androgen receptor with IC50 value of 0.1903 nM.

The opening segments give a summary of the history of catalysis in general and of frustrated Lewis pairs in particular, where both intra- and intermolecular types are discussed. In addition, the essences of the mechanisms of action of frustrated Lewis pairs are discussed, covering electric field, electron transfer and radical-type mechanisms. There is also a discussion on the activity of frustrated Lewis pairs towards dehydrogenation reactions, in which lies the main scope of this thesis. The background and intended parameters of the experimental aspects of this work are initially defined in the thesis scope, along with the practical considerations concerning the reagents, equipment, and special conditions for synthetic procedures also detailed here. The intention was to attempt to elucidate the extent of the impact of different factors, in this case solvent, Lewis acidity, Lewis basicity, and irradiation by blue LED, on dehydrogenation of various N-substituted pyrrolidine substrates. The subsequent section describes the synthetic procedures used for attempted syntheses of the amino-borane ligands. Not all syntheses of the desired ligands were successful, but there was enough success and enough pre-generated material to proceed to the next stage. Due to use of blue LED causing various potential radical side reactions, it was thought appropriate to describe the behaviour of both the sample and substrate blanks under irradiation, as well as the intended reactions during the screening process. Screening provided preliminary data on reaction determining factors, such as solvent, Lewis acidity of the catalyst, and substrate structure. Despite the relative difficulty and time-consuming nature of the catalyst syntheses, some interesting new modes of reactivity appear to be accessible, which may be worth investigating more in the future.

In this thesis, synthesis and solution properties of the polyampholyte poly(acrylic acid)-b-poly[(vinylbenzyl)trimethylammonium chloride], PAA-PVBTMA-Cl, were investigated in aqueous solutions. First, the diblock copolymer was synthesized via RAFT polymerization where poly(acrylic acid), PAA was used as a chain transfer agent (CTA). In addition, the homopolymer poly[(vinylbenzyl)trimethylammonium chloride], PVBTMA-Cl, was synthesized via RAFT polymerization to compare the solution properties with the block copolymer. Molar masses of the polymers were determined using several methods such as NMR, UV-Vis spectroscopy and SEC. The experimental molar masses were close to theoretical values and block ratio in diblock copolymer from NMR was 30% of AA and 70% of VBTMA-Cl. Furthermore, the solution properties of the polyampholyte were studied under external stimuli such as pH and temperature. UCST type of behaviour was observed for aqueous PAA-PVBTMA-Cl solutions when the hydrophobic trifluoromethanesulfonate (OTf) anion was introduced. In addition, self-assembly of the diblock copolymer was confirmed by zeta potential measurements in different pH conditions. The expected reverse of the micelle structure with changing pH was not observed. However, aqueous PAA-PVBTMA-Cl showed UCST behaviour and micellization induced by the hydrophobic counterion.

It is quite rare to find 6-substituted pyrimidines in nature due to the difficulty involved in directly introducing a substituent to the 6-position whereas other synthetic analogues of naturally occurring nucleosides like 5-substituted derivatives are more common. The aim was to synthesize 3',5'-O,O-bis(tert-butyldimethylsilyl)-6-phenyl-2'-deoxyuridine by carrying out a direct nucleophilic substitution of 3',5'-O,O-bis(tert-butyldimethylsilyl)-6-cyano-2'-deoxyuridine with the Grignard reagent: phenyl magnesium bromide in the presence of zinc (II) chloride catalyst. The first step was silylation of commercially available 2'-deoxyuridine and subsequent bromination at the 5-position to give 3',5'-O,O-bis(tert-butyldimethylsilyl)-5-bromo-2'-deoxyuridine. This was reacted with the nucleophile KCN to yield a product with the cyano substitute at the 6-position via intramolecular nucleophilic substitution. The final step was to introduce an aryl substituent to the 6-position to yield the target molecule.

Terephthalic acid (TPA) is a monomer used widely in the production of poly(ethylene terephthalate) (PET) and other polyesters. The other monomer of PET, ethylene glycol, can already be produced from bioethanol. However, TPA is still produced via the traditional route from petrochemical sources, but the global demand for environmental-friendly options has increased throughout the past years making the synthesis of bio-based TPA an attractive research target. Several companies have formed a collaborative to support the development of 100% bio-based PET and thus bio-based TPA. The challenge is not only to develop an ecologically beneficial but also a cost-effective process. In the literature section of this work, the current methods to produce bio-based TPA have been reviewed. A highly attractive option is to use lignocellulosic biomass - cellulose, hemicellulose and lignin - as the starting material due to its high abundance and low cost. Lignocellulosic biomass can be utilized directly via biotechnical pathways by using either catalytic fast pyrolysis or fermentation and reforming strategies. The other option is to convert it into small platform chemicals, for instance HMF, furfural and acrolein, which are then used in Diels–Alder approaches to get TPA or its precursors. Besides lignocellulose, other viable starting materials, like monoterpenes, have been discussed. The experimental of the thesis is focused on N-heterocyclic carbene (NHC)-catalyzed umpolung reactions in order to make TPA-precursors and other value-added chemicals from benzaldehyde. The research hypothesis was that by forming an electron-rich enaminol, called Breslow intermediate, from benzaldehyde and NHC, we could reverse the reactivity of benzaldehyde from ortho,para-deactivating to ortho,para-activating. Two NHC-precursors were synthesized, isolated and characterized. Several pathways utilizing both two-electron and single-electron transfer were attempted, but unfortunately no success in these reactions was achieved.

Boron Neutron Capture Therapy is a binary cancer treatment based on the nuclear capture and fission reaction which occur when 10B is irradiated with low energy thermal neutrons. BNCT has throughout the years shown noticeable clinical results with the boron delivery agents that are currently available for testing. However, these delivery agents display deficiencies on multiple frontiers. My goal was to synthesize three different carbohydrate delivery agents for BNCT. Carbohydrate delivery agents have great potential for multiple reasons. They have low toxicity, high aqueous solubility and a high amount of boron atoms can be attached to a single molecule. These three synthesized molecules, 6-O-o-carboranylmethyl-D-glucopyranose, (O)-carboranylmethyl -D-glucopyranoside, (O)-carboranylmethyl -D-glucopyranoside, consist out of a glucose moiety and a carborane cage at both anomeric positions 1 as well as position 6. The synthetic pathways developed were 5-6 steps long and the overall yields varied between 13-15%. The synthesized molecules are currently undergoing biological evaluation.

In this master's thesis research reversible addition-fragmentation chain-transfer polymerization (RAFT) was utilized to synthesize primary and tertiary amine-based cationic copolymers to be utilised as micelles for gene transfer. Materials that were synthesized included 2-aminoethyl methacrylamide hydrochloride (AEMA.HCl) monomer, homopolymers such as polymethyl methacrylate (PMMA) and poly (N,N-dimethylamino ethyl methacrylate) (PDAMEMA), and copolymers such as polymethyl methacrylate-block-poly (2-dimethylamino) ethyl methacrylate (PMMA-b-PDMAEMA), polymethylmethacrylate-block-poly(dimethylamino ethyl methylcrylate-statistical-2-aminoethyl methacrylamide hydrochloride) (PMMA-b-P[DMAEMA-co-AEMA.HCl]) and poly (dimethylamino ethyl methylcrylate-statistical-2-aminoethyl methacrylamide hydrochloride) (P[DMAEMA-co-AEMA.HCl]). Prepared polymers were characterized using nuclear magnetic resonance (NMR) spectroscopy and size exclusion chromatography (SEC) methods. Also, via dialysis method aqueous micelles of PMMA-b-PDMAEMA block copolymer were prepared, and charaterized using dynamic light scattering (DLS). AEMA-hydrochloride monomer was synthesized via amidation process using methacrylic anhydride, and purified by recrystallization in isopropanol. Proton Neutron Magnetic Resonance (1HNMR) results revealed successful synthesis and production of a highly pure monomer. PMMA and PDMAEMA homopolymers of narrow molecular weight distribution were synthesized via RAFT using azobisisobutyronitrile (AIBN) initiator and 4-cyano-4-(phenylcarbonothioylthio) pentanoic acid (CPA) as chain transfer agent (CTA). With PMMA as a macro-CTA and AIBN initator DMAEMA was polymerized resulting in the formation of PMMA-b-PDMAEMA cationic block copolymer. 1HNMR analysis revealed a polymer consisting of PMMA and PDMAEMA blocks, and size exclusion chromatography (SEC) results also indicated production of a polymer with narrow molecular weight distribution. Results from dynamic light scattering (DLS) study showed PMMA-b-PDMAEMA (Mn=~23000 g/mol) diblock copolymer forms micelles with hydrodynamic radius in the range of 10-100 nm when THF-based copolymer solution was dialyzed in water. The size of micelle decreased at higher pH values. With respect to size PMMA-b-PDMAEMA copolymer micelles could be considered suitable for DNA transfer. Also, with AIBN initiator CPA and PMMA were used as CTA and a macro-CTA in two separate reactions to polymerize DMAEMA and AEMA-hydrochloride monomers simultaneously leading to formation of P(DMAEMA-co-AEMA.HCl) and PMMA-b-P(DMAEMA-co-AEMA.HCl) copolymers respectively. It was observed through SEC polymerization occured in both cases and resulting polymers exhibit very narrow molecular weight distribution. However, the molecular nature and composition of both copolymers cannot be reliably predicted based on 1HNMR results due to complications as a result of polymers poor solubility in various NMR solvents.

Nowadays one main objective in chemistry is to find environmentally benign alternatives to non-biodegradable materials, like common plastics. Further, as fossil resources are decreasing, novel approaches to utilize renewable materials (like biomass), are becoming increasingly important for the mankind. There is a long-standing interest for utilization of cellulose; it is the most abundant polymer on earth and can be found in many organisms such as plant, algae, and bacteria but also in some animal species. Cellulose is the most abundant biogenic polymer used in the world; its largest source is from wood, which contains up to 50% of cellulose but also other compounds such as lignin (up to 30%), hemicellulose (up to 30%), inorganic salts and proteins. The main challenge is to dissolve cellulose, because of is strong intra- and intermolecular hydrogen bonding, it is not soluble in common molecular organic solvents and does not melt. According to these problems of cellulose dissolution, a novel class of solvents has been designed and called: Ionic liquids (ILs). ILs are made of an organic cation and an organic or inorganic anion, their major difference from classic salts is their lower melting point (under 100°C) They are able to do covalent and ionic bonds as normal organic solvent do, but their special character comes from the fact that ILs are able to do also strong H-bonding and columbic interactions. The mechanism of the dissolution itself has been studied using molecular dynamics and it has been shown that the anion and cellulose build a strong hydrogen-bonding network between them; the cation has a different stabilizing effect on dissolution as it is dominated by Van der Walls and electrostatic interactions. The structure of the IL plays a big role. A non-hindered cation will be more effective and, an anion with high basicity will be the most effective. Many of the ILs studied to dissolve cellulose contain phosphonium cations or halogen anions, such combination leads to toxicity and corrosive action against reaction vessels. To diminish the negative effects, other combinations have to be designed. Chemist started to use superbases as a cation and weak acid such as acetic acid as an anion to form superbase-based ILs. ILs-based on guanidine are known to be chemically and thermally stable, this comes from the high proton delocalisation between the three nitrogen atoms. Even if they are able to dissolve cellulose, their characteristics related to their structure such as high melting point and high viscosity are a problem for lab experiments using a classic magnetic stirring. Also they are limited to 10 wt% cellulose dissolution. A lot of superbase ILs such as immidazolium-based ILs were investigated for cellulose dissolution but they require temperature higher than 90°C enhancing cellulose degradation. So bicyclic guanidine were investigated as a potential class of ILs. Because of their rigid bicyclic structure, they are less affected by steric effect than their acyclic analogue. This explains why chemists started to be interested in bicyclic guanidine species in ILs such as TBD and its methylated version mTBD.

Continuous delivery is an approach to software development which incorporates the practices, technologies and processes in order to achieve frequent delivery of valuable software to customers. Even though the continuous delivery approach has not existed very long yet, there has been quite a lot of a buzz around it and terms related to it (continuous deployment, deployment pipeline, and DevOps). Practices and benefits of the approach are presented in the literature, and organizations have been adopting it to a varying extent. However, as easy as the advocates of continuous delivery make the adoption look like, there have been reported challenges along the way. In order to focus research on finding the causes and creating solutions to these challenges, we must first identify them. To address this, we conducted a systematic literature review in order to collect perceived challenges related to the adoption of continuous delivery practices in software development projects, and analyzed the findings in order to provide synthesized information about these challenges. From among 13 publications 59 different challenges were identified which we categorized either as a social (procedural or organizational) or as a technical type of a challenge based on the evaluation of the findings. Among these challenges we found 14 more frequently occurring ones which also spanned across multiple software domains. We described these as common challenges. We also analyzed the reasons behind these challenges and identified five different themes (main reasons) that were immaturity, unsuitability, complexity, dependency, and security. We also analyzed how the software domain affected these reasons. Based on the observed mitigation strategies and research proposals, and our analysis, we proposed suggestions for future research directions. This study can be used as a support for finding future research directions regarding the challenges in the area of adopting continuous delivery practices in software development projects.