Condensation of vinyl triflate (I) with 5-mercapto-7-oxo-thienothiopyran (II) in the presence of diisopropylethylamine afforded the thiovinyl cephem (III). The Boc protecting group of (III) was then removed by treatment with p-toluenesulfonic acid to give amine (IV), which was coupled with hydroxyimino acid (V) to furnish amide (VI). Finally, deprotection of (VI) by means of trifluoroacetic acid gave rise to the title compound.