Maintaining normal cell homeostasis between synthesis and degradation of proteins is crucial for the proper functioning of the body. The proteasome is a key mechanism in the eukaryotic organisms that ensures optimum degradation of intracellular proteins. The constitutive proteasome is expressed in most eukaryotic cells whereas immunoproteasome is only expressed in the cells of the immune system. Structurally, both types of proteasomes are very similar, differing only in three catalytic β subunits. At the moment, there are three non-selective proteasome inhibitors approved by the FDA; the main problem of these inhibitors is the high presence of adverse effects. Designing and synthesis of selective immunoproteasome inhibitors would allow for new therapeutic possibilities in the treatment of autoimmune disorders and cancer therapy.The purpose of the master thesis was the design and synthesis of selective covalent immunoproteasome inhibitors, that would bind to the active site of threonine in a catalytic subunit LMP-7. We wanted the compounds first to bind non-covalently to the subunit LMP-7 and thus approach the active site of threonine protease. Then, the inhibitors would covalently bind the electrophilic "warhead" to the catalytic theronine. We decided to introduce chloroacetamide, methyleneoxirane and epoxyketone electrophilic centers to a substituted aminopiperidine skeleton. Our starting compounds were Boc protected 3-aminopiperidine and 4-aminopiperidine. The fundamental mechanism of most reactions was nucleophilic substitution, except for acidolysis. Before removing the Boc protecting group, an amide was formed on the free nitrogen with the use of acid chlorides and coupling reagents. The aminopiperidine skeleton protected with Boc was substituted with biphenyl-4-carbonyl chloride. We also synthesized the aminopiperidine skeleton to which 4-morpholinobenzoic acid was added using coupling reagents. Subsequently, Boc-protecting group was removed from the compounds and three free electrophilic centers joined to the free amine group through the amide bond. We successfully synthesized four compounds with a chloroacetamide "warhead", one with an ethylenoxirane "warhead" and three epoxyketones "warhead" inhibitors. All eight compounds will be biochemically evaluated on isolated subunits LMP-7 of immunoproteasome.
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