Synthesis of novel heterocyclic compounds having azole rings

In this study, the synthesis of new hybrid compounds containing some combinations of Norfloxacin and Ciprofloxacin with several heterocyclic units was perfomed. For this purpose, Norfloxacin and Siprofloxacin were condensed with 3,4-difluoronitrobenzen, and the nitro group of the obtained nitro compounds were reduced to amine (63, 106). The treatment of 63 and 106 with several iso(thio)cyanates produced the corresponding carbo(thio)amides (64-67, 109). The condensation of the intermediates (64 and 66) with ethyl bromoacetate and 2-bromo-1-(4-chlorophenyl)ethanone yielded 1,3-thiazole derivatives (68-71). The synthesis of 1,3,4-oxadiazoles (75, 110), 1,2,4-triazoles (79, 80 ve 81) and 1,3,4-thiadiazole (82) was carried out starting from 63 and 106 via several steps. 1,3,4-oxadiazoles (85, 94) and 1,2,4-triazoles (89-91, 99-101) was obtained starting from Norfloxacin and Ciprofloxacin via several steps and then, were converted to Mannich bases (102-104) by the treatment with N-phenyl piperazine. In the last part of the study, the ester obtained from the condensation of 1-(4-nitrophenyl)piperazine with ethyl bromoacetate was converted to 1,2,4-triazole (116, 117) derivatives via several steps. The treatment of 116 and 117 with Norfloxacine and Ciprofloxacine afforded Mannich bases (118, 119). Microwave irradiation was used beside conventional methods. The stuructures of newly synthesized compounds were eluciated by spectroscopic techniques, and antimicrobial activities were investigated.