Načrtovanje, sinteza in vrednotenje 5-stirilnikotinonitrilnih zaviralcev monoamin oksidaz, holin esteraz in ligaz Mur

Doblekar, Zala (author), Frlan, Rok (mentor)

Monoamin oksidaza (MAO) je encim, ki preko oksidativne deaminacije aminov pripomore k ohranjanju homeostaze biogenih aminov in s tem uravnava nadzor nad čustvovanjem, razpoloženjem, zaznavanjem, presojo, razumom in drugimi kognitivnimi funkcijami. Obstajata dva izoencima MAO: MAO-A in MAO-B, ki sta vezani na zunanjo mitohondrijsko membrano in spadata v skupino flavoencimov. Zaviralci posameznega encima se trenutno uporabljajo pri zdravljenju depresije in Parkinsonove bolezni. Acetilholinesteraza (AChE) in butirilholinesteraza (BChE) sta encima, ki hidrolizirata živčni prenašalec acetilholin (ACh) v ocetno kislino in holin. Inhibitorji AChE se uporabljajo v terapevtske namene, saj je znižana koncentracija acetilholina prisotna pri bolnikih z Alzheimerjevo boleznijo in še nekaterih drugih boleznih. Zaviralci BChE so zaenkrat še predmet raziskovanja, vendar kažejo obetavne rezultate za njihovo bodočo uporabo pri zdravljenju Alzheimerjeve bolezni. Povečano nastajanje patogenih bakterijskih vrst z visoko odpornostjo proti antibiotični terapiji predstavlja resno nevarnost javnemu zdravju. Encimi ligaze Mur imajo pomembno vlogo v začetnih stopnjah izgradnje bakterijskega peptidoglikana in predstavljajo odlično tarčo bodočim protibakterijskim učinkovinam. Namen dela je bila sinteza novih potencialnih zaviralcev MAO, ligaz Mur, AChE in BChE. Laboratorijsko delo je v glavnem obsegalo sintezo derivatov 5-stirilnikotinonitrila, ki smo jim na koncu izmerili zaviralno aktivnost na vse omenjene encime. Struktura derivatov je bila načrtovana na osnovi znanih zaviralcev omenjenih encimov, ki so bili predhodno sintetizirani na Katedri za farmacevtsko kemijo, Fakultete za farmacijo, Univerze v Ljubljani. Poudarek je bil na izvajanju Heckove reakcije, katere največji problem so bili slabi izkoristki. Sintetizirane spojine z dovolj velikim izkoristkom smo poskusili pretvoriti v derivate 3-stiril-5-(1H-tetrazol-5-il)piridina, ki so se tudi že izkazali kot zaviralci ligaz Mur. Izmed vseh sintetiziranih spojin se je najbolje izkazala spojina 5-(4-metoksi-3-nitrostiril)nikotinonitril, z IC50 vrednostjo 0.425 µM na encimu MAO-B, kar je odličen rezultat in daje možnosti za razvoj novih učinkovin na področju zdravljenja Parkinsonove in drugih nevrodegenerativnih bolezni.

• Language: Slovenian
• Keywords: MAO, acetilholinesteraza, butirilholinesteraza, nevrodegenerativne bolezni, zaviralci, encimi Mur, peptidoglikan, protibakterijske učinkovine
• Work type: Master's thesis/paper
• Organization: FFA - Faculty of Pharmacy
• Year: 2020
• PID: 20.500.12556/RUL-114784
• Publication date in RUL: 10.03.2020

Secondary language

• Language: English
• Title: Design, synthesis and evaluation of 5-styrylnicotinonitrile inhibitors of monoamine oxidases, cholin esterases and Mur ligases

Abstract

Monoamine oxidase (MAO) helps to maintain the homeostasis of biogenic amines through oxidative deamination of amines and thereby regulates emotions, mood, perception, judgement and other cognitive functions. There are two MAO isoenzymes: MAO-A and MAO-B, which are bound to the outer mitochondrial membrane and belong to the group of flavoenzymes. Currently, enzyme inhibitors are being used in the treatment of depression and Parkinson's disease. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) are enzymes, that hydrolyze the nerve transporter acetylcholine (ACh) to acetic acid and choline. Because of decreased concentrations of acetylcholine in Alzheimer's and several other diseases, AChE inhibitors are used for several therapeutic purposes. BChE inhibitors are still in development but could also be used to treat Alzheimer's disease in the future. The increased production of pathogenic bacterial species with high resistance to antibiotic therapy poses a serious public health threat. Mur enzymes play an important role in the initial stages of bacterial peptidoglycan biosynthesis and represent an excellent target for future antibacterial agents. The purpose of our work was to synthesize new potential inhibitors of MAO enzymes, inhibitors of Mur ligases and inhibitors of AChE and BChE. The laboratory work mainly involved the synthesis of 5-styrylnicotinonitrile derivatives, for which we measured the inhibitory activity against these enzymes. The structure of derivatives was designed based on known inhibitors which have already been synthesized at the Department of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Ljubljana. The syntheses were performed mainly with Heck reaction, with the biggest problem of extremely poor yields. We tried to convert synthesized compounds with sufficient yield to 3-styryl-5-(1H-tetrazol-5-yl) pyridine derivatives, which have already proven to be inhibitors of Mur ligases. Out of all synthesized compounds, 5-(4-methoxy-3-nitrostyryl)nicotinonitrile, with an IC50 value of 0.425 µM on the MAO-B enzyme, proved to be the best inhibitor, which provides potential for the development of new active substances in the field of Parkinson's and other neurodegenerative diseases.

• Keywords: MAO, acetylcholinesterase, butyrylcholinesterase, neurodegenerative diseases, inhibitors, Mur enzymes, peptidoglycan, antibacterial agents