CAS No:106560-14-9(free acid),122547-49-3(Sodium Salt) ||Chemical Formula:C12H14NNaO5S||Molecular Weight:307.29577 ||Exact Mass:307.04904||sodium (5R,6S)-6-((R)-1-hydroxyethyl)-7-oxo-3-((R)-tetrahydrofuran-2-yl)-4-thia-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylate