Synthesis and antitumor effects of a new class of 1,2,4-triazole derivatives

In order to obtain more effective antitumor agents, a new class of 1,2,4-triazole derivatives bearing disulfide bond were designed and synthesized. All the final compounds were confirmed by IR, 1H NMR, 13C NMR and HR-ESI-MS. The in vitro cytotoxicity of the compounds on the SMMC-7721, Hela, A549 cancer cell lines and the L929 normal cell lines were assessed by cell counting kit-8 (CCK-8). Many of tested compounds 8a–h, 9a–h, 10a–h had better cytotoxic activity on various cancer cell lines than positive control 5-fluorouracil, and they were less cytotoxic to normal cell line L929 than cancer cells. Among them, compounds 9e, 9g, and 10h showed better cytotoxic activity on SMMC-7721 cells with IC50 values 4.12, 2.92, and 4.53 μM, respectively. Compounds 8a, 9g, 10g and 10h displayed high antiproliferative activity against Hela cells with IC50 values 6.31, 4.31, 6.31 and 3.97 μM, respectively. Compounds 8c, 10a and 10h revealed effective biological potency on A549 cells with IC50 values 4.75, 4.92 and 3.73 μM, respectively. Moreover, a great majority of tested compounds revealed low cytotoxicity on normal cell line L929.