novel 5-(nitrothiophene-2-yl)-1,3,4-thiadiazole derivatives: synthesis and antileishmanial activity against promastigote stage of leishmania major

In this study, a series of novel compounds based on 5 -(5-nitrothiophene2--yl)-1,3,4- thiadiazole possessing (het) aryl thio pendant at c-2 position of thiadiazole ring is developed and evaluated as antileishmanial agents using mtt colorimetric assay. 10 new compounds containing aryl and heteroaryl derivatives, started from thiophene-2-carbaldehyde in five steps, were synthesized in good to excellent yields and characterized by ^1h-nmr, ^13c-nmr, and ir spectroscopy. through the compounds 6a-j, methylimidazole containing derivative 6e was recognized as the most active compound against l. major promastigotes exhibiting ic_50 values of 11.2μg/ml and 7.1μg/ml after 24 and 48 h, respectively. this compound is > 4 fold more effective than glucantime as a standard drug (ic_50 = 50 μg/ml after 24 h and 25 μg/ml after 48 h).