Synthesis And Antimicrobial Activities Of Novel Triazoles

The research and development of triazoles as medicinal agents have become one of important fields in medicinal chemistry. This thesis based on the current situation of triazoles and triazoliums as antifungal and antibacterial agents, designed and synthesized a series of novel triazolyl prop-2-en-1-one and 2-en-1-ol compounds as well as triazolium salts (mono triazolium salts and bis-triazolium salts), and evaluated the antimicrobial activities of synthesized new compounds. The target triazolyl enone compounds were prepared by the condensation reaction of 1-(2,4-difluorophenyl)-2-(1H-1,2,4-triazol-1-yl) ethanone with a series of aromatic aldehydes, and then were reduced to afford the desired triazolyl prop-2-en-1-ol compounds. The triazolium salts were synthesized by the N-alkylation of 1,2,4-triazole with 2,4-dichlorobenzyl chloride and then quaternization with a series of alkyl bromides or dibromides. The synthesized compounds were confirmed by UV-Vis, IR, 1H NMR, 13C-NMR and MS. The in vitro antimicrobial activities showed that the synthesized novel triazolyl prop-2-en-1-ones and 2-en-1-ols displayed good activities against fungi. Especially, triazolyl prop-2-en-1-ols 27a and 28 showed better activity against C.albicans than fluconazole in clinic use. Some triazolyl prop-2-en-1-one and 2-en-1-ol compounds also showed good activity against bacteria. Among tested compounds, triazolyl allylidene piperidinium 22 showed the strongest activity against S.aureus and E.coli and get close to the norfloxacin. Some of prepared new triazoliums also showed efficient activities against bacteria. Biphenyl methylene triazolium 39 showed the better activity against S.aureus. These compounds are promising for next research as antimicrobial agents.