6-Chloro-3-nitro-8-(phenylthio)-2-[(phenylthio)methyl] imidazo[1,2-a]pyridine

As part of our ongoing antikinetoplastid structure-activity relationship study focused on positions 2 and 8 of the 3-nitroimidazo[1,2-a]pyridine scaffold, we were able to introduce a phenylthioether moiety at both position 2 and position 8 in one step. Using a previously reported synthetic route developed in our laboratory, we obtained 6-chloro-3-nitro-8-(phenylthio)-2-[(phenylthio)methyl]imidazo[1,2-a]pyridine in 74% yield. The in vitro cell viability of this compound was assessed on the HepG2 cell line, and its in vitro activity was evaluated against the promastigote form of L. donovani, the axenic amastigote form of L. infantum and the trypomastigote blood stream form of T. b. brucei. It showed low solubility in HepG2 culture medium (CC50 > 7.8 & mu;M), associated with weak activity against both the promastigote form of L. donovani (EC50 = 8.8 & mu;M), the axenic amastigote form of L. infantum (EC50 = 9.7 & mu;M) and the trypomastigote blood stream form of T. b. brucei (EC50 = 12.8 & mu;M).