© 2022 Indian Chemical SocietyCarbazol derivatives, 4-(((9-ethyl-9H-carbazol-3-yl)methylene)amino)-5-methyl-2,4-dihydro-3H-1,2,4-triazole-3-one (3) and 5-benzyl-4-(((9-ethyl-9H-carbazol-3-yl) methylene) amino)-2,4-dihydro-3H-1,2,4-triazole-3-one (4), were synthesized. Compounds 3 and 4 were characterized by The Fourier transform infrared (FTIR), proton and carbon-13 nuclear magnetic resonance (1H- and 13C- NMR) spectroscopic methods. Density Functional Theory (DFT) calculations for compounds 3 and 4 were performed at B3LYP/6–311++G(d,p) level. Optimized geometry, IR and NMR parameters of compounds 3 and 4 were obtained. The in vitro anti-acetylcholinesterase activity of the compounds were examinated. In addition, Compounds 3 and 4 were tested to determine possible interactions against human acetylcholinesterase by in silico analysis.