The molecular complexes of the Chaperone family are fundamental and very relevant regulators of some biological cycles, such as the organization of enzymatic complexes, the traffic and regulation of the activity of signaling molecules and also the resistance to protein drugs[1], but many of the molecular mechanisms underlying their functions are unknown or uncertain. Most of the functions are sequential cycles of ATPase activity, whereby binding, hydrolysis and release of the nucleotide drive the conformational changes of the complex, but it is also an inhibitor of both cytochrome c oxidase, a component of oxidative phosphorylation (OXPHOS), both of the succinate dehydrogenase (SDH) at the intersection between OXPHOS and the tricarboxylic acid cycle[2],[3], also provides resistance to oxidative stress, counteracts the transition of mitochondrial permeability and the consequent cell death; in tumors, these TRAP1 activities contribute to the metabolic shift of cells to aerobic glycolysis and resistance to oxidative stress[11] and inhibition of TRAP1-dependent SDH that stimulates stabilization of HIF1a, a transcription factor with crucial pro-neoplastic activities. The design and synthesis of targeted small molecules, able to inhibit or stimulate its activity, can pave the way to finely dissect its biochemical activity and pave the way for possible drugs. In my thesis work I specialized in the synthesis of molecules with tetrazole or imidazole ends and in particular with a thiol group capable of attacking a variously derivatized epoxide to obtain different structures. The thiolysis of epoxides therefore offers an efficient and simple synthetic approach to access β-hydroxy sulfides, valuable scaffolds in the synthesis of various important molecules in medicinal chemistry. A general overview in this topic recently suggests various methodologies for obtaining the desired products from varying starting compounds under specific experimental conditions. In this work, we have exploited the methodology relating to the opening of the epoxy ring belonging to epichlorohydrin or glycidol and other derivatives under experimental conditions that are not extreme and easily reproducible. The optimized protocol was applied in several cases obtaining the desired products (figure 1) with very good yields and excellent purity. Further investigations are currently underway to increase yield and seek other avenues that do not include the use of the aforementioned partners. Finally, for the study on the inhibition of the HSP90 protein complex, the samples of all the synthesized compounds were sent to the Department of Biomedical Sciences of the University of Padua (Prof. A. Rasola) for biological tests.
I complessi molecolari della famiglia Chaperone sono regolatori fondamentali e molto rilevanti di alcuni cicli biologici, come l'organizzazione dei complessi enzimatici, il traffico e la regolazione dell'attività delle molecole di segnalazione e anche la resistenza ai farmaci proteici[1], ma molti di i meccanismi molecolari alla base delle loro funzioni sono sconosciuti o incerti. La maggior parte delle funzioni sono cicli sequenziali dell'attività dell'ATPasi, per cui il legame, l'idrolisi e il rilascio del nucleotide guidano i cambiamenti conformazionali del complesso, ma è anche un inibitore sia della citocromo c ossidasi, un componente della fosforilazione ossidativa (OXPHOS), sia della succinato deidrogenasi (SDH) all'intersezione tra OXPHOS e il ciclo degli acidi tricarbossilici[2],[3], fornisce anche resistenza allo stress ossidativo, contrasta la transizione della permeabilità mitocondriale e la conseguente morte cellulare; nei tumori, queste attività di TRAP1 contribuiscono allo spostamento metabolico delle cellule alla glicolisi aerobica e alla resistenza allo stress ossidativo [11] e all'inibizione della SDH dipendente da TRAP1 che stimola la stabilizzazione di HIF1a, un fattore di trascrizione con attività pro-neoplastiche cruciali. La progettazione e la sintesi di piccole molecole mirate, in grado di inibire o stimolare la sua attività, può aprire la strada per sezionare finemente la sua attività biochimica e aprire la strada a possibili farmaci. Nel mio lavoro di tesi mi sono specializzato nella sintesi di molecole con estremità tetrazoliche o imidazoliche ed in particolare con un gruppo tiolico in grado di attaccare un epossido variamente derivatizzato per ottenere strutture differenti. La tiolisi degli epossidi offre quindi un approccio sintetico efficiente e semplice per accedere ai β-idrossi solfuri, preziosi scaffold nella sintesi di varie importanti molecole in chimica medicinale. Una panoramica generale in questo argomento suggerisce di recente varie metodologie per ottenere i prodotti desiderati da composti di partenza variabili in condizioni sperimentali specifiche. In questo lavoro abbiamo sfruttato la metodologia relativa all'apertura dell'anello epossidico appartenente all'epicloridrina o al glicidolo e altri derivati in condizioni sperimentali non estreme e facilmente riproducibili. Il protocollo ottimizzato è stato applicato in diversi casi ottenendo i prodotti desiderati (figura 1) con ottime rese e ottima purezza. Sono attualmente in corso ulteriori indagini per aumentare la resa e cercare altre strade che non prevedano l'utilizzo dei suddetti partner. Infine, per lo studio sull'inibizione del complesso proteico HSP90, i campioni di tutti i composti sintetizzati sono stati inviati al Dipartimento di Scienze Biomediche dell'Università degli Studi di Padova (Prof. A. Rasola) per i test biologici.
Sintesi di composti tetrazolici ed imidazolici come potenziali modulatori allosterici di TRAP1
D'ACERNO, GIOVANNI
2019/2020
Abstract
The molecular complexes of the Chaperone family are fundamental and very relevant regulators of some biological cycles, such as the organization of enzymatic complexes, the traffic and regulation of the activity of signaling molecules and also the resistance to protein drugs[1], but many of the molecular mechanisms underlying their functions are unknown or uncertain. Most of the functions are sequential cycles of ATPase activity, whereby binding, hydrolysis and release of the nucleotide drive the conformational changes of the complex, but it is also an inhibitor of both cytochrome c oxidase, a component of oxidative phosphorylation (OXPHOS), both of the succinate dehydrogenase (SDH) at the intersection between OXPHOS and the tricarboxylic acid cycle[2],[3], also provides resistance to oxidative stress, counteracts the transition of mitochondrial permeability and the consequent cell death; in tumors, these TRAP1 activities contribute to the metabolic shift of cells to aerobic glycolysis and resistance to oxidative stress[11] and inhibition of TRAP1-dependent SDH that stimulates stabilization of HIF1a, a transcription factor with crucial pro-neoplastic activities. The design and synthesis of targeted small molecules, able to inhibit or stimulate its activity, can pave the way to finely dissect its biochemical activity and pave the way for possible drugs. In my thesis work I specialized in the synthesis of molecules with tetrazole or imidazole ends and in particular with a thiol group capable of attacking a variously derivatized epoxide to obtain different structures. The thiolysis of epoxides therefore offers an efficient and simple synthetic approach to access β-hydroxy sulfides, valuable scaffolds in the synthesis of various important molecules in medicinal chemistry. A general overview in this topic recently suggests various methodologies for obtaining the desired products from varying starting compounds under specific experimental conditions. In this work, we have exploited the methodology relating to the opening of the epoxy ring belonging to epichlorohydrin or glycidol and other derivatives under experimental conditions that are not extreme and easily reproducible. The optimized protocol was applied in several cases obtaining the desired products (figure 1) with very good yields and excellent purity. Further investigations are currently underway to increase yield and seek other avenues that do not include the use of the aforementioned partners. Finally, for the study on the inhibition of the HSP90 protein complex, the samples of all the synthesized compounds were sent to the Department of Biomedical Sciences of the University of Padua (Prof. A. Rasola) for biological tests.È consentito all'utente scaricare e condividere i documenti disponibili a testo pieno in UNITESI UNIPV nel rispetto della licenza Creative Commons del tipo CC BY NC ND.
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https://hdl.handle.net/20.500.14239/12860