Napoved fizikalno-kemijskih lastnosti in silico ter eksperimentalno vrednotenje cis/trans izomerizacije selektivnih zaviralcev butirilholin esteraze

Oblak, Jurij (author), Pajk, Stane (mentor), Knez, Damijan (co-mentor)

Raziskave na področju Alzheimerjeve bolezni (AB) in odkrivanju novih zdravilnih učinkovin v zadnjih letih močno napredujejo. Ob napredovanju AB se zviša koncentracija in aktivnost encima butirilholin esteraza (BChE), ki je v zadnjem desetletju postal zanimiva farmakološka tarča za blaženje kognitivnega upada v poznih stadijih bolezni. Namen magistrske naloge je bil, da po že razviti sintezni poti ponovimo sintezo najbolj perspektivnega zaviralca humane (h)BChE, njegovih cis in trans analogov, in silico vrednotimo fizikalno-kemijske in učinkovini podobne lastnost celotne serije zaviralcev ter da z NMR spektroskopijo preverimo izomerizacijo cis/trans dvojne vezi 2-fluorofenilnih analogov pod vplivom svetlobe. Po opisanih sinteznih postopkih z manjšimi modifikacijami smo uspešno opravili sintezo 2-fluorofenetilnega ter cis in trans 2-fluorofenilnih zaviralcev hBChE na gramski skali. Pripravljene spojine smo nato uporabili za vrednotenje izomerizacije cis/trans dvojne vezi s protonsko NMR spektroskopijo pod vplivom naravne sončne svetlobe ter pri obsevanju z živosrebrovo žarnico. Izomerizacijo cis/trans dvojne vezi bi lahko alternativno spremljali tudi z UHPLC metodo, ki smo jo razvili in je pod optimiziranimi kromatografskimi pogoji ločila cis (8) in trans (7) izomera 2-fluorofenilnih zaviralcev hBChE. Na podlagi NMR spektroskopije smo ugotovili, da je termodinamsko manj stabilen cis derivat 8 pod vplivom sončne svetlobe izomeriziral do trans derivata po 21 dneh v manj kot 5 % deležu, medtem ko je pri obsevanju z živosrebrovo žarnico v 14 dneh nastalo približno 10 % trans izomera. Pri in silico vrednotenju fizikalno-kemijskih in učinkovinam podobnim lastnosti lahko izpostavimo, da vse spojine ustrezajo kriterijem po Lipinskem in imajo ustrezne lastnosti za dobro prehajanje krvno-možganske pregrade, kar je pomembno za doseganje mesta delovanja ter zaviralcev. Serija spojin je tako zaradi svojih dobrih zaviralnih aktivnosti na encimu BChE in ustreznih fizikalno-kemijskih lastnosti dobra odskočna deska za nadaljnji razvoj in optimizacijo selektivnih zaviralcev hBChE.

• Language: Slovenian
• Keywords: Alzheimerjeva bolezen, butirilholin esteraza, zaviralci butirilholin esteraze, izomerizacija dvojne vezi
• Work type: Master's thesis/paper
• Organization: FFA - Faculty of Pharmacy
• Year: 2021
• PID: 20.500.12556/RUL-128125
• Publication date in RUL: 03.07.2021

Secondary language

• Language: English
• Title: In silico prediction of physicochemical properties and experimental evaluation of cis/trans isomerization of selective butyrylcholinesterase inhibitors

Abstract

Research in the field of Alzheimer's disease (AD) and the discovery of drugs has advanced significantly in recent years. As AD progresses, the concentration and activity of the enzyme butyrylcholinesterase (BChE) increases. Therefore, BChE has become an interesting pharmacological target to alleviate cognitive decline in the late stages of the disease. The primary aim of the Master's thesis was to resynthesize the most promising inhibitors of human (h)BChE, its cis and trans analogues, and to evaluate the physicochemical and drug-like properties of the series of selective BChE inhibitors, and to study the isomerization of cis/trans double bonds of 2-fluorophenyl analogs under the influence of light. Following the procedures described, the synthesis of 2-fluorophenethyl and cis and trans 2-fluorophenyl BChE inhibitors on a gram scale was successfully performed. The compounds synthesized were used to evaluate the isomerization of the cis/trans double bond by proton NMR spectroscopy under the influence of natural sunlight and under irradiation using a mercury lamp. Alternatively, the isomerization of the cis/trans double bond could also be monitored by the UHPLC method developed, which separated the cis (8) and trans (7) isomers of 2-fluorophenyl hBChE inhibitors under optimized chromatographic conditions. Based on NMR spectroscopy, we established that the thermodynamically less stable cis derivative 8 under the influence of sunlight isomerized to the trans derivative after 21 days in less than 5 % portion. On the other hand, the irradiation with a mercury lamp for 14 days yielded about 10 % of the trans isomer. The in silico evaluation of physicochemical and drug-like properties pointed out that all the compounds meet the Lipinski criteria and have appropriate properties for good crossing of the blood-brain barrier, which is important for achieving the site of action of the inhibitors. Given the potent BChE inhibition and the suitable physicochemical properties, the series of compounds is a good springboard for further development and optimization of selective hBChE inhibitors.

• Keywords: Alzheimer’s disease, butyrylcholinesterase, butyrylcholinesterase inhibitors, double bond isomerization