20.500.12556/RUL-186966 Sinteza alkoholnih bioizosterov karboksilne kisline za razvoj zaviralcev DNA-giraze in paneksina 1 Synthesis of alcohol-based carboxylic acid bioisosteres for the development of DNA gyrase and pannexin 1 inhibitors Karboksilna kislina je ena najpogosteje zastopanih funkcionalnih skupin v zdravilnih učinkovinah, vendar njeno uporabo pogosto omejujejo neugodne farmakokinetične lastnosti. Eden od pristopov za njihovo izboljšanje je bioizosterna zamenjava karboksilne kisline. V magistrski nalogi smo ta pristop uporabili pri razvoju šestih bioizosternih analogov benzotiazolnega zaviralca DNA-giraze ULD1 ter šestih bioizosternih analogov probenecida kot zaviralca paneksina 1. Karboksilno kislino smo nadomestili z alkoholnimi in ketonskimi bioizosteri, pri nekaterih analogih pa uvedli tudi trifluorometilni fragment. Za sintezo smo uporabili redukcijo ketonov z natrijevim borhidridom, nukleofilno adicijo Grignardovega oziroma Ruppert–Prakashevega reagenta, tvorbo benzotiazolnega obroča z in situ generiranim tiocianogenom in asimetrično katalitsko hidrogeniranje. Zaviralce DNA-giraze smo ovrednotili na rekombinantni DNA-girazi bakterije Escherichia coli ter določili njihovo protibakterijsko aktivnost proti sevom E. coli in Staphylococcus aureus. Najmočnejšo zaviralno aktivnost je izkazovala spojina 3 (IC50 = 0,64 μM), sledila pa ji je spojina 10. Nobena spojina ni delovala proti sevom E. coli. Najizrazitejše delovanje proti S. aureus je izkazovala spojina 11 (MIK = 64 μg/mL), ki najverjetneje deluje po mehanizmu, neodvisnem od zaviranja DNA-giraze. Spojina 10 je bila edina spojina, ki je zavirala DNA-girazo in hkrati delovala protibakterijsko proti S. aureus. Določili smo tudi logD in termodinamsko topnost vseh spojin. Pri analogih ULD1 je bioizosterna zamenjava povečala lipofilnost in zmanjšala topnost, medtem ko so analogi probenecida ohranili razmeroma ugodne fizikalno-kemijske lastnosti. Trifluorometilketonski analog 18 je izkazoval nepričakovano nizko vrednost logD in dobro topnost, najverjetneje zaradi hidracije do geminalnega diola. Analoge probenecida smo preliminarno ovrednotili v celičnem modelu THP-1 z merjenjem sproščanja interlevkina IL-1β po stimulaciji s PAM3CSK4. Pri koncentraciji 2 mM so vsi analogi zmanjšali sproščanje IL-1β brez povečanja sproščanja laktat dehidrogenaze, kar kaže, da učinek ni posledica citotoksičnosti. Rezultati magistrske naloge kažejo, da bioizosterna zamenjava karboksilne kisline pomembno vpliva na fizikalno-kemijske lastnosti spojin, pri čemer je njen učinek odvisen od molekulskega ogrodja in izbrane biološke tarče. Carboxylic acid is one of the most common functional groups in drug molecules; however, its application is often limited by unfavourable pharmacokinetic properties. One approach to improve these properties is the bioisosteric replacement of the carboxylic acid moiety. In this master's thesis, this strategy was applied to the development of six bioisosteric analogues of the benzothiazole-based DNA gyrase inhibitor ULD1 and six bioisosteric analogues of probenecid as a pannexin 1 inhibitor. The carboxylic acid group was replaced with alcohol- and ketone-based bioisosteres, while a trifluoromethyl group was introduced into selected analogues. The compounds were synthesized using sodium borohydride reduction of ketones, nucleophilic addition of Grignard or Ruppert–Prakash reagents, benzothiazole ring formation using in situ generated thiocyanogen, and asymmetric catalytic hydrogenation. The DNA gyrase inhibitors were evaluated against recombinant Escherichia coli DNA gyrase, and their antibacterial activity was determined against E. coli and Staphylococcus aureus strains. Compound 3 exhibited the highest inhibitory activity (IC50 = 0,64 μM), followed by compound 10. None of the compounds were active against E. coli. The strongest activity against S. aureus was observed for compound 11 (MIC = 64 μg/mL), most likely through a mechanism independent of DNA gyrase inhibition. Compound 10 was the only compound that inhibited DNA gyrase while also exhibiting antibacterial activity against S. aureus. The logD values and thermodynamic solubility of all compounds were also determined. Bioisosteric replacement increased lipophilicity and decreased solubility of the ULD1 analogues, whereas the probenecid analogues retained relatively favourable physicochemical properties. The trifluoromethyl ketone analogue 18 exhibited an unexpectedly low logD value and good solubility, most likely due to hydration to the corresponding geminal diol. The probenecid analogues were preliminarily evaluated in a THP-1 cell model by measuring interleukin-1β (IL-1β) release following stimulation with PAM3CSK4. At a concentration of 2 mM, all analogues reduced IL-1β release without increasing lactate dehydrogenase release, indicating that the observed effect was not due to cytotoxicity. The results of this master's thesis demonstrate that bioisosteric replacement of the carboxylic acid moiety significantly affects the physicochemical properties of the compounds, with the outcome depending on the molecular scaffold and the selected biological target. benzotiazol bioizoster karboksilna kislina paneksin 1 trifluorometil benzothiazole bioisoster carboxylic acid pannexin 1 trifluoromethyl true false false [M. Šubic] Slovenski jezik Angleški jezik Magistrsko delo/naloga 2026-09-08 08:45:04 2026-09-08 08:45:21 2026-09-21 10:51:11 0000-00-00 00:00:00 2026 0 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 1970-01-01 547(043.2) 128359 290919427 33116.pdf 33116.pdf 1 54CFA469FD52B408ACD89AE1CFE34304 788ff111838586b5a6d32d445e8a3a2691b601c4fec11e45d6f9941ab91cf048 da21659c-ab50-11f1-8bc5-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=246372 Fakulteta za farmacijo 0 0 0