Thioamide derivatives were oxidized with sodium hypochlorite to converted to the corresponding amides. When the reactions of thioamides with sodium hypochlorite were carried out in methylene chloride at room temperature, the corresponding amides were obtained in good yields. However, the primary thioamides were interestingly cyclized to 1,2,4-thiadiazoles in excellent yields. The oxidation reactions of pyridine 2-thiol moieties afforded the corresponding disulfides in quantitative at short reaction time. 2-Pyridylketone hydrazones and amidines were oxidatively cyclized into the corresponding 1,2,3-trizolo(1,5a) pyridines and s-triazolo(1,5a) pyridines, respectively.