A new method for regioselective synthesis of a broad-spectrum parenteral S-3578-related cephalosporin bearing an imidazo[4,5-b]pyridinium derivative at C-3'

A broad-spectrum S-3578-related cephalosporin, 7β-[2-(5-amino-1,2,4-thiadiazol-3-yl)-2(Z)-fluoromethoxyiminoacetamido]-3-[1-(3-methylaminopropyl)-1H-imidazo[4,5-b]pyridinium-4-yl]methyl-3-cephem-4-carboxylate sulfate was regioselectively synthesized in a good yield using diaminopyridine derivative bearing a dimethylformamidine group.