Sintesi e Caratterizzazione di Elettrodi Modificati Chimicamente con nuovi complessi Carbenici del Ferro

The Chemically Modified Electrodes (CME) are widely used in electroanalytical chemistry as chemical sensors. The interest in the covalent anchoring of a redox mediator on the electrode surface is increasing, because it allows the sensibility and the selectivity of this kind of systems to improve. My work is situated in this field of research and involves the synthesis of new Iron(0) complexes that contain cyclopentadienone, N-heterocyclic carbene (NHC) and carbonyl ancillary ligands. These complexes have shown electrochemical properties similar to those of ferrocene (organometallic compound widely used as electrochemical sensor). These complexes have been properly functionalized with a EDOT group in the NHC ligand side chain that it was after used for the realization of Electrochemically Modified PEDOT thanks to copolymerization reaction between the functionalized complex and the EDOT in different amounts. All the synthetic steps were assisted by suitable characterizations (NMR, IR, ESI-MS, cyclic voltammetry and X-ray for the monomeric compound as imidazolium salt and NHC functionalized complexes; cyclic voltammetry, IR e SEM for the copolymers). The properties of the polymer as a selective sensor was preliminarily investigated for dopamine and 2-propanol.

N-Heterocyclic carbene complexes of silver, rhodium and iron: structures, dynamics and catalysis

The research performed in the framework of this Master Thesis has been directly inspired by the recent work of an organometallic research group led by Professor Maria Cristina Cassani on a topic related to the structures, dynamics and catalytic activity of N-heterocyclic carbene-amide rhodium(I) complexes1. A series of [BocNHCH2CH2ImR]X (R = Me, X = I, 1a’; R = Bz, X = Br, 1b’; R = trityl, X = Cl, 1c’) amide-functionalized imidazolium salts bearing increasingly bulky N-alkyl substituents were synthetized and characterized. Subsequently, these organic precursors were employed in the synthesis of silver(I) complexes as intermediate compounds on a way to rhodium(I) complexes [Rh(NBD)X(NHC)] (NHC = 1-(2-NHBoc-ethyl)-3-R-imidazolin-2-ylidene; X = Cl, R = Me (3a’), R = Bz (3b’), R = trityl (3c’); X = I, R = Me (4a’)). VT NMR studies of these complexes revealed a restricted rotation barriers about the metal-carbene bond. However, while the rotation barriers calculated for the complexes in which R = Me, Bz (3a’,b’ and 4a) matched the experimental values, this was not true in the trityl case 3c’, where the experimental value was very similar to that obtained for compound 3b’ and much smaller with respect to the calculated one. In addition, the energy barrier derived for 3c’ from line shape simulation showed a strong dependence on the temperature, while the barriers measured for 3a’,b’ did not show this effect. In view of these results and in order to establish the reasons for the previously found inconsistency between calculated and experimental thermodynamic data, the first objective of this master thesis was the preparation of a series of rhodium(I) complexes [Rh(NBD)X(NHC)] (NHC = 1-benzyl-3-R-imidazolin-2-ylidene; X = Cl, R = Me, Bz, trityl, tBu), containing the benzyl substituent as a chiral probe, followed by full characterization. The second objective of this work was to investigate the catalytic activity of the new rhodium compounds in the hydrosilylation of terminal alkynes for comparison purposes with the reported complexes. Another purpose of this work was to employ the prepared N-heterocyclic ligands in the synthesis of iron(II)-NHC complexes.

Synthesis and functionalization of a lactam-pyrazole molecular scaffold as a promising anticancer compound

The importance of pyrazole and lactam-based molecules in medical and pharmaceutical fields is underlined by the multitude of active ingredients on trade, such as Sildenafil or Apixaban, by Pfizer. In this work, a synthesis of an organic molecule with promising anticancer activity has been developed. This molecular scaffold is characterized by a δ-lactam-fused pyrazolic core, with a well-known biological activity and amenable of further functionalization. The synthetic strategy adopted for the obtainment of the core was based on a 1,3-dipolar cycloaddition of a nitrilimine with an α,β-unsaturated δ-lactam. Secondly, in order to give the final compound an elevated pharmacological activity, a functionalization with a double “side chain”, namely molecular fragment able to improve the interaction with particular biological receptors, was achieved. The target compound was thus obtained, with a highly convergent synthesis, and will be tested for antiproliferative activities towards different cellular lines.

In vivo and in vitro effects of genistein as obesogenic/anti-obesogenic compound in the lipid metabolism of rainbow trout (Oncorhynchus mykiss)

Nowadays, soy is one of the most used ingredients in the formulation of fish feed, due to the ample market supply, lower market price, high protein concentration and favorable amino acid composition. Nevertheless, soybean meal products are rich and primary diet source of phytoestrogens, as genistein, which may have a potential negative impact on growth, hormonal regulation and lipid metabolism in fish. The principal aim of this study was to better understand in vivo and in vitro genistein’s effects on lipid metabolism of rainbow trout. In adipose tissue it was showed an unclear role of genistein on lipid metabolism in rainbow trout, and in liver an anti-obesogenic effect, with an up-regulation of autophagy-related genes LC3b (in adipose tissue) and ATG4b (in liver and adipose tissue), a down-regulation of apoptosis-related genes CASP3 (in adipose tissue) and CASP8 (in liver). An increase of VTG mRNA levels in liver was also observed. Genistein partially exerted these effects via estrogen- receptor dependent mechanism. In white muscle, genistein seemed to promote lipid turnover, up-regulating lipogenic (FAS and LXR) and lipolytic (HSL, PPARα and PPARβ) genes. It seemed that genistein could exert its lipolytic role via autophagic way (up-regulation of ATG4b and ATG12l), not through an apoptotic pathway (down-regulation of CASP3). The effects of genistein on lipid-metabolism and apoptosis-related genes in trout muscle were not dose-dependent, only on autophagy-related genes ATG4B and ATG12l. Moreover, a partial estrogenic activity of this phytoestrogen was also seen. Through in vitro analysis (MTT and ORO assay), instead, it was observed an anti-obesogenic effect of genistein on rainbow trout adipocytes, and this effect was not mediated by ERs. Both in vivo and in vitro, genistein exerted its effects in a dose-dependent manner.

Analisi del ciclo di lavorazione di un compound polimerico

La tesi riguarda il ciclo di lavorazione di un compound polimerico realizzato dall'impresa forlivese So.F.Ter. . Il prodotto in esame, Polifor E 30 TR/20 UV Nero, è un tecnopolimero a base di polipropilene utilizzato nel settore dell'automobile per la realizzazione del fascione sottoporta e del passaruota. La tesi si sviluppa su tre capitoli attraverso i quali si descrivono, nel primo capitolo, le materie plastiche in generale e i prodotti realizzati dall'impresa, nel secondo capitolo il ciclo di lavorazione completo partendo dalla fase di miscelazione arrivando all'estrusione e al taglio nei granuli plastici. Infine nel terzo capitolo si rappresentano le analisi fisiche, meccaniche e termiche realizzate in laboratorio.