Synthesis and In Vitro Anti-Leishmanial Evaluation of 1-(5-Halo-2-Thienyl)-2-[5-(5-Nitroheteroaryl)]-1,3,4-Thiadiazol-2-Ylthio)Ethanone Derivatives

The Leishmaniasis is a zoonotic disease that remains a severe public health problem and its burden is increasing. By now there is no anti-leishmaniasis vaccine and as other tripanosomial disease, is treated by limited drugs. First line drug includes pentavalent antimony such as sodium stibogluconat and meglumine antimoniate that use of these drugs is limited due to side effects, long term treatment, high cost and incidence of drug resistance. It is clear that developing new, effective, cheap and safe drugs is necessary for treating Leishmaniasis. In this study new derivatives of 1-(5-halo-2-thienyl)-2-[5-(5-nitroheteroaryl)]-1,3,4-thiadiazol-2-ylthio)ethanone 8a-8d were synthesized and evaluated against the promastigote form of Leishmania major using MTT assay in comparison with control drug (Fluconazole). Concentrations (5-150 µg/mL) of synthesized compounds and control drug were prepared and IC50 for each compound was measured. IC50 for 8a-8d was 114.98 µM (44.59±8.15 µg/mL), 118.05 µM (51.25±9.08 µg/mL), 130.7 µM (52.78±12.97 µg/mL), and 252.7 µM (113.3±5.92 µg/mL) respectively that was less than of fluconazole 980 µM (300 µg/mL). The results of this study showed that four synthesized compounds had a significant effect on Leishmania major and have a stronger effect than control drug. It seems that these compounds can be used as an alternative in future.