Novel 3-substituted N-methylcarbazole–imidazolium salt derivatives: Synthesis and cytotoxic activity

A series of novel 3-substituted N-methylcarbazole–imidazolium salt derivatives has been prepared and evaluated in vitro against a panel of tumor cell lines (Hep G-2, Hela and PC12). The results suggest that the presence of substituted 2-methyl-imidazole or imidazole ring and substitution of the imidazolyl-3-position with a naphthylacyl or 4-bromophenacyl group were important for improving cytotoxic activity. Compounds 17, 18, 27, and 28 with 4-bromophenacyl and naphthylacyl groups displayed good activities with IC50 values of 0.09–7.20 μm against three tumor cell lines investigated and more active than DDP. Compound 35 exhibited cytotoxic activity selectively against Hela cell.