Novel functionalized 1,2,3-triazole derivatives exhibit antileishmanial activity, increase in total and mitochondrial-ROS and depolarization of mitochondrial membrane potential of Leishmania amazonensis

1,2,3-triazolium salts are poorly understood regarding their antileishmanial activity. Hence, as an effort to identify novel chemical scaffolds as antileishmanial agents, a series of 1,2,3-triazolium salts (TS) and corresponding 1,2,3-triazole (T) precursors including new epoxide derivatives were synthesized and assayed against Leishmania amazonensis promastigote and intracellular amastigote forms. Among them, the compound TS-6 exhibited promising activity on promastigotes (IC50 = 3.61 mu M) and intracellular amastigotes (IC50 = 7.61 mu M) of L. amazonensis, superior to miltefosine (IC50 > 10.0 mu M), used as reference drug. In addition, TS-6 showed negligible cytotoxicity on murine peritoneal macrophages with a SI of about 10. Studies on the mode of action of TS-6 indicate mitochondrial dysfunction through an increase in 'total' and mitochondrial-ROS as well as depolarization of mitochondrial membrane potential of L. amazonensis promastigotes. In silico physicochemical studies indicate that the TS-6 could potentially be used as an oral drug.