Copper (I) Catalyzed Synthesis and Antibacterial activity of 1,2,3-Triazoles Based on D-Fructose


Four n-alkyl azides; n-heptyl azide, n-octyl azide, n-decyl azide and n-dodecyl azide (1a-d) were prepared via SN2 reaction of alkyl halides and sodium azide. In different step, D-fructose was converted to 2,3:4,5-di-O-isopropylidene-D-fructopyranose (3) using acetone and sulfuric acid as catalyst. The reaction of compound (3) with propargyl bromide in DMF afforded the terminal acetylene (4) in very good yield. The derivative (4) was reacted with synthesized n-alkyl azides (1a-d) via cycloaddition reaction using Cu(I) as catalyst afforded D-fructose based 1,2,3-triazoles (5a-d). The acetal groups of triazoles (5a-d) were removed under acidic conditions to give the deprotected triazoles (6a-d). All synthesized compound were identified by TLC, FTIR and most of them were characterized by 1H NMR, 13C NMR, COSY, HSQC and HRMS. The synthesized compounds showed antibacterial activity in vitro against two kinds of bacteria: Escherichia coli (-) and Staphylococcus aureus (+).