A simple and economical method for the synthesis of intermediates of cefazolin

A simple convenient method of synthesis of 2-mercapto-5-methyl-1,3,4-thiadi azole (MMTD) is described. Hydrazine hydrate, ethyl acetate and carbon disu lphide were used as the starting materials and transformed into the target molecule in three steps. MMTD was later converted into 7-Amino-3-{[(5-methy l-1,3,4-thiadiazole-2-yr)thio]methyl}-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2 -ene-2-carboxylic acid, a main drug intermediate of cefazolin.