CAS No: 15686-71-2(Cephalexin monohydrate CAS No:23325-78-2)||Chemical Formula:C16H17N3O4S||Molecular Weight:347.38900||Exact Mass:347.09398||}(6R,7R)-7-[(R)-2-Amino-2-phenylacetamido]-3-methyl-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid