. "5-{(6R,7R)-7-[2-[(Z)-2-(Acetyl-hydroxy-amino)-ethoxyimino]-2-(2-amino-thiazol-4-yl)-acetylamino]-2-carboxy-8-oxo-5-thia-1-aza-bicyclo[4.2.0]oct-2-en-3-ylmethylsulfanyl}-2,3-dihydro-1H-imidazo[1,2-a]pyridin-4-ylium" . "11b" . . . . . . . . . . . . . . . . .