Metalation of 7-iodoimidazo[5,1-b]thiazole (I) with ethylmagnesium bromide, followed by addition to 3-pyridinecarboxaldehyde (II) provides carbinol (III), which is further oxidized to ketone (IV) by means of MnO2. Lithiation of (IV) and further treatment with chlorotributyltin affords the stannyl derivative (V). The carbapenem ketone (VI) is converted into the vinyl triflate (VII) upon treatment with trifluoromethanesulfonic anhydride and diisopropyl ethylamine. Then, Stille coupling between vinyl triflate (VII) and the stannyl derivative (V) gives rise to the imidazothiazolyl carbapenem (VIII). Quaternization of the pyridine ring of (VIII) with iodoacetamide furnishes the pyridinium salt (IX). Finally the p-nitrobenzyl ester group of (IX) is removed by hydrogenolysis over Pd/C to provide the title compound