[3-[5-[2-fluoro-4-[2-oxo-5-(triazol-1-ylmethyl)-1,3-oxazolidin-3-yl]phenyl]-2-pyridinyl]-4,5-dihydro-1,2-oxazol-5-yl]methyl 1-oxidopyridin-1-ium-3-carboxylate