Sinteza i strukturna karakterizacija novih N-supstituiranih derivata imidazo[4,5-b]piridina

undergraduate thesis

• Title (english): Synthesis and structural characterization of new N-substituted derivatives of imidazo[4,5-b]pyridine
• Author: Corina Šljubura
• Mentor: Marijana Hranjec (mentor)
• Committee member: Marijana Hranjec (predsjednik povjerenstva)
• Committee member: Dragana Vuk (član povjerenstva)
• Committee member: Kristina Starčević (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2021-07-14, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry

Abstract

Derivati imidazo[4,5-b]piridina, svestrani purinski izosteri, važna su skupina heterocikličkih spojeva jer pokazuju širok spektar biološkog djelovanja. U ovom radu opisana je sinteza i strukturna karakterizacija novih N-supstituiranih derivata imidazo[4,5-b]piridina. Ciljani spojevi priređeni su klasičnim reakcijama organske sinteze te sinteze potpomognute mikrovalovima. U prvom koraku sinteze, mikrovalovima potpomognutom aminacijom 2-klor-3-nitropiridina 1 uz odgovarajući amin priređeni su spojevi 2 i 3. Diamino supstituirani derivati 4 i 5 priređeni su redukcijom kataliziranom s Pd/C. Iz spojeva 4 i 5 u reakciji ciklokondenzacije s esterom priređeni su glavni prekursori 7, 8 i 9. Reakcijom aldolne kondenzacije iz glavnih prekursora 7, 8 i 9 te odgovarajućih aromatskih aldehida 10-12 priređeni su iminokumarinski derivati 13-23. Amino supstituirani iminokumarin 18 priređen je redukcijom spoja 17 s SnCl2x2H2O. Kod spojeva 20 i 22 utvrđeno je postojanje smjese iminokumarina i pentacikličkog derivata 21 i 23. Kolonskom kromatografijom iz smjese su uspješno razdvojeni spojevi 20 i 21, dok je iz smjese spoja 22 izoliran samo pentaciklički derivat 23. Strukture novopriređenih spojeva potvrđene su 1H i 13C NMR spektroskopijom, kao i MS spektrometrijom. Ispitana je antioksidativna aktivnost priređenim spojevima metodama DPPH i FRAP.

Abstract (english)

Imidazo[4,5-b]pyridine derivatives, versatile purine isosters, are an important group of heterocyclic compounds since they exhibit a broad spectrum of biological activity. This work describes the synthesis and structural characterization of new N-substituted derivatives of imidazo[4,5-b]pyridine. The targeted compounds were prepared by using the standard reactions of organic synthesis and microwave-assisted synthesis. In the first step of the synthesis, compounds 2 and 3 were prepared by microwave-assisted amination of 2-chloro-3-nitropyridine 1 with the corresponding amine. Diamino-substituted derivatives 4 and 5 were prepared by the reduction of catalyzed by Pd/C. The main precursors 7, 8 and 9 were prepared from compounds 4 and 5 in reaction cyclocondensations with ester. Iminocoumarin derivatives 13-23 were prepared in the reaction of aldol condensation from the main precursors 7, 8 and 9 and the corresponding aromatic aldehydes 10-12. Amino-substituted iminocoumarin 18 was prepared by reduction of the compound 17 with SnCl2x2H2O. Compounds 20 and 22 were found to have mixtures of iminocoumarins and pentacyclic derivatives 21 and 23. Column chromatography was used to separate compounds 20 and 21, while only pentacyclic derivative 23 was isolated from mixture 22. The structures of the newly prepared compounds were confirmed by 1H and 13C NMR spectroscopy as well as MS spectrometry. The antioxidative activity of prepared compounds was determinate by using DPPH and FRAP method.

• Keywords: imidazo[4 5-b]piridini; aminacija; ciklokondenzacija; redukcija; MW potpomognuta sinteza; 1H NMR i 13C NMR spektroskopija; MS spektrometrija; antioksidativna aktivnost
• Keywords (english): imidazo[4 5-b]pyridines; amination; cyclocondensation; reduction; microwave-assisted synthesis; 1H and 13C NMR spectroscopy; MS spectrometry; antioxidative activity
• Language: croatian
• URN:NBN: urn:nbn:hr:149:172986
• Project: Number: IP-2018-01-4379; Title: Istraživanje antioksidativnog djelovanja benzazolskog skeleta u dizajnu novih antitumorskih agensa; Acronym: AntioxPot; Leader: Marijana Hranjec; Jurisdiction: Croatia; Funder: HRZZ; Funding stream: IP
• Study programme: Title: Applied Chemistry - Undergraduate study; specializations in: Environmental chemistry and green technologies, Advanced materials and technologies, Applied organic chemistry; Course: Applied organic chemistry; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) primijenjene kemije (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) primijenjene kemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Closed access
• Created on: 2023-04-24 09:42:03