A series of substituted 1, 3, 4-thiadiazoles (3a-w) were prepared by oxidative cyclization of aryl substituted thiosemicarbazones. Synthesized compounds were identified on the basis of their spectral data. The compounds 3a, 3e, 3m, 3n, 3o, 3p and 3v showed more lipophilic character and moderate protection in MES test whereas compounds 3d and 3e were also lipophilic and less active. Some of the compounds have shown up to 83 % protection and obviously may have very good future commitment.