| Abstract | U okviru ovog rada provedena je sinteza, spektroskopska karakterizacija i antioksidativna aktivnost novih metoksi- i hidroksi- derivata amino supstituiranih benzamida, benzamidnih derivata benzimidazola, 2-benzimidazola te hidrokloridnih soli benzamida, 2-benzimidazolil i 2-benzotiazolil supstituiranih benzamida. Novi spojevi priređeni su klasičnim reakcijama organske sinteze. Kondenzacijom odgovarajućih supstituiranih benzoil-klorida 2, 14, 15 i 41 s odgovarajućim aminom 3, 4, 16 ili 2-amino-5(6)-nitrobenzimidazolom 42 priređeni su metoksi supstituirani benzamidi 5, 6, 17, 18 i 43. Amino supstituirani derivati 7, 8, 19, 20 i 44 priređeni su reakcijom redukcije sa SnCl2×2H2O. Hidroksi supstituirani derivati benzamida 21 i 22 priređeni su uklanjanjem zaštitnih metoksi skupina korištenjem reagensa BBr3. Hidroksi derivat nitro supstituiranog benzimidazola 30 priređen je reakcijom kondenzacije benzojeve-kiseline 27 s 4-nitro-1,2-fenilendiaminom 29, dok su metoksi derivati cijano supstituiranog benzimidazola 36-38 priređeni reakcijom kondenzacije odgovarajućeg aromatskog aldehida 32-34 s p-cijano-1,2-fenilendiaminom 35, a uklanjanjem zaštitne metoksi skupine korištenjem reagensa BBr3 priređeni su hidroksi derivati cijano supstituiranog benzimidazola 39 i 40. Hidrokloridne soli priređene su reakcijom protoniranja amino supstituiranih derivata benzamida 9, 10, 23, 24, 25, 26, 52, 53, 54 i 55, 2-benzimidazolil supstituiranih benzamida 47, 64, 65 i 66 i 2-benzotiazolil supstituiranih benzamida 61, 62 i 63. Priređenim derivatima 5, 6, 7, 8, 17, 18, 19, 20, 21 i 22 dodatno su ispitane spektroskopske karakteristike korištenjem UV/Vis spektroskopije. Kako bi se ispitala mogućnost primjene spojeva 7, 8, 19, 20, 21 i 22 kao optičkih pH senzora, ispitana je i promjena njihovih spektroskopskih svojstava ovisno o vrijednosti pH otopine korištenjem UV/Vis spektroskopije. Ispitana je i antioksidativna aktivnost korištenjem DPPH i FRAP metode. Spojevi 22, 26, 62 i 63 pokazali su značajnu antioksidativnu aktivnost. |
| Abstract (english) | This work presents the synthesis, spectroscopic characterization and antioxidative activity of novel methoxy- and hydroxyl- derivatives of amino substituted benzamides, benzamide derivatives of benzimidazole, 2-benzimidazole derivatives and hydrochloride salts of benzamides, 2-benzimizolyl and 2-benzothiazolyl substituted benzamides. Novel compounds were prepared by classical reactions of organic chemistry. Due to the condensation of substituted benzoyl-chlorides 2, 14, 15 and 41 with corresponding amine 3, 4, 16 or 2-amino-5(6)-nitrobenzimidazole 42 methoxy substituted benzamides 5, 6, 17, 18 and 43 were prepared. Amino substituted derivatives 7, 8, 19 and 20 were prepared by reduction of nitro analogues with SnCl2×2H2O. By the removal of methoxy protecting groups with BBr3, hydroxy substituted benzamide derivatives 21 and 22 were synthesized. Hydroxy derivative of nitro substituted benzimidazole 30 was prepared in the cyclocondensation from benzoic acid 27 with 4-nitro-1,2-phenylenediamine 29 while methoxy derivatives of cyano substituted benzimidazole 36-38 were prepared in the cyclocondensation from aromatic aldehyde 32-34 with 4-cyano-1,2-phenylenediamine 35. By the removal of methoxy protecting groups with BBr3, hydroxy derivatives cyano substituted benzimidazole 39 and 40 were synthesized. Hydrochloride salts were prepared by protonation reaction of amino substituted derivatives benzamides 9, 10, 23, 24, 25, 26, 52, 53, 54 and 55, 2-benzimidazolyl substituted benzamides 47, 64, 65 and 66 and 2-benzothiazolyl substituted benzamides 61, 62 and 63. In addition, the spectroscopic properties of prepared compounds 5, 6, 7, 8, 17, 18, 19, 20, 21 and 22 were studied by UV/Vis and fluorescence spectroscopy. In order to determine the possibility of compounds 7, 8, 19, 20, 21 and 22 for analytical applications as pH sensors, the changes of their spectroscopic properties depending on the pH value were studied by UV/Vis spectroscopy. Also, the antoxidative activity of chosen compounds was determined by DPPH and FRAP method. Compounds 22, 26, 62 and 63 showed the most pronounced activity. |
