Synthesis and characterization of new 1,2,4-triazole-3-thione derivates derived from l-tyrosine

There are five member heterocyclic compounds in the structure of many drugs. We aimed to synthesize the 1,2,4-triazole derivatives in the five member heterocyclic structure. In this matter L-Tyrosine ethyl ester is used as starting material. In the first stage L-Tyrosine ethyl ester reacted with 4-methoxybenzoylchloride in chloroform and amine morety [1] was converted to amide derivative. In the second stage, the amide derivative [1] to obtain hydrochloride and hydrazine monohydrate were reacted in the methanolic medium thus the ester side of the compound was converted to derivative [1] to hydrazine [2]. In the third stage, the hydrazide derivative compound [2] is allowed to react with the 4-substitutedphenyl isothiocyanates in the ethanolic medium to give the thiosemicarbazide derivatives [3a-3o]. In the last stage, the obtained thiosemicarbazide derivatives [3a-3o] were cyclized in the sodium hydroxide medium to give 1,2,4-triazole-3-thione derivatives [4a-4o]. All of the reactions were followed by Thin Layer Chromatography (TLC). After the crude products were pruficated, their melting points were determined. The chemical structures of all compounds were characterized by elemental analysis and spectroscopic techniques such as IR, UV-Vis, 1H NMR, 13C NMR, and Mass Spectroscopy (MS).