The reaction of 2-(2-sulfanylthiazol-4-yl)acetic acid ethyl ester (I) with ammonia and ammonium chloride gives the corresponding acetamide (II), which is condensed with the cephem methanesulfonate (III) by means of potassium tert-butoxide in dimethoxyethane to yield the diphenylmethyl ester (IV) of the target compound, which is finally hydrolyzed with trifluoroacetic acid and anisole.

In an alternative method, benzhydryl ester (V) was cleaved with trifluoroacetic acid to give carboxylic acid (VI). After protection of (VI) by means of trimethylsilyl acetamide, the triflate group was displaced by the potassium salt of mercapto thiadiazole (III) to furnish the title compound.