Glu(Tau), a bioactive substance previously isolated from the protein free aqueous extract of bovine parathyroid powder, has been synthesized. The intermediate derivative Z-Glu(Tau)-OBzl was prepared in three different ways from Z-Glu-OBzl and (1) cystamine by using the mixed anhydride method followed by oxidation, (2) Tau by the active ester procedure via Z-Glu-(ONp)-OBzl, (3) Tau applying mixed anhydride coupling. The protecting groups were removed by hydrogenolysis.