20.500.12556/RUL-147321 Halogeniranje kvercetina Halogenation of quercetin 2-(3,4-dihidroksifenil)-3,5,7-trihidroksi-4H-1-benzopiran-4-on, bolj znan pod trivialnim imenom kvercetin, je kot eden najpomembnejših predstavnikov flavonoidov znan po svojih antioksidativnih, protivirusnih, protivnetnih in protirakavih lastnostih. Zaradi nizke biološke razpoložljivosti pa se postavlja vprašanje o njegovih možnih modifikacijah z namenom uporabe v medicini in farmaciji. Odgovor bi se lahko skrival v halogeniranih derivatih, ki izkazujejo visoko biološko aktivnost. V okviru diplomskega dela smo uspešno sintetizirali in izolirali tri halogenirane derivate kvercetina: 8-bromokvercetin, 6,8-dibromokvercetin in 6-klorokvercetin. Bromiranje smo izvedli na dva načina, klasično z reagentom N-bromosukcinimidom in oksidativno z uporabo sistema HBr-H2O2. Tako z uporabo N-bromosukcinimida kot pod oksidativnimi pogoji smo sintetizirali mono- in dibromiran derivat kvercetina. Skupne prednosti obeh postopkov se kažejo v enostavni izvedbi in blagih reakcijskih pogojih, saj ni potrebna neposredna uporaba elementarnega broma. Poleg tega pa je prednost metode z vodikovim peroksidom tudi v boljših okoljskih parametrih, saj se reagent regenerira med potekom reakcije, pri tem pa nastaja voda kot edini stranski produkt. Z uporabo oksidativnega sistema HBr-H2O2 smo uspeli identificirati tudi stranski produkt halogeniranj, ki nastane kot posledica oksidacije kvercetina, 2-(3,4-dihidroksibenzoil)-2,4,6-trihidroksi-3(2H)-benzofuranon. Kloriranje smo izvedli z uporabo reagenta N-klorosukcinimida, pri čemer je nastal le monokloriran derivat kvercetina. 2-(3,4-dihydroxyphenyl)-3,5,7-4H-1-benzopyran-4-one, commonly known as quercetin is, as one of the most important representatives of flavonoids, known for its antioxidant, antiviral, anti-inflammatory and anticarcinogenic properties. Due to its low bioavailability, intensive research efforts have been focused on possible modifications of the molecule with the aim of medical and pharmaceutical application. The answer could lie in its halogenated derivatives that exhibit high biological activity. We have successfully prepared and isolated three halogenated derivatives of quercetin: 8-bromoquercetin, 6,8-dibromoquercetin and 6-chloroquercetin. Bromination was performed in two different ways, with N-bromosuccinimide as reagent and with oxidative system HBr-H2O2. The synthesis of mono- and dibromo derivates of quercetin was successful with both methods. The advantages of both methods are their simple procedure and mild reaction conditions, as they do not require direct use of elemental bromine. Above that, the benefit of using the oxidative method is in its better environmental parameters, as the reactive species is regenerated during the reaction and water is the only by-product. Using the oxidative system HBr-H2O2, we have also successfully identified and isolated one of the by-products present in halogenation reactions, resulting from oxidation of quercetin, 2-(3,4-dihydroxybenzoyl)-2,4,6-trihydroxy-3(2H)-benzofuranone. Furthermore, chlorination was performed with N-chlorosuccinimide and only monochlorinated derivative of quercetin was formed. kvercetin flavonoidi halogeniranje N-bromosukcinimid vodikov peroksid quercetin flavonoids halogenation oxidation N-bromosuccinimide hydrogen peroxide true false false Slovenski jezik Angleški jezik Diplomsko delo/naloga 2023-06-30 10:20:00 2023-06-30 10:20:05 2023-07-27 13:50:44 0000-00-00 00:00:00 2023 0 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 21986 159934723 Stih_Lara_marusa_-_Halogeniranje_kvercetina.pdf Stih_Lara_marusa_-_Halogeniranje_kvercetina.pdf 1 F5C05E79CD97ADFCA4CBC47009E15D30 66d144d51f3f370c6cb76fc116d355790e7fdfc4f64e107ba1faa80c5f1b4651 8467b6b6-171e-11ee-a314-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=170856 Fakulteta za kemijo in kemijsko tehnologijo 0 0 0