Figure 1
The chemical structure and formula of Pemetrexed disodium (A) and Cefixime trihydrate (B). (A) C20H21N5O6 (2R)-2-[[4-[2-(2-amino-4-oxo-1,7- dihydropyrrolo[2,3-d]pyrimidin-5-yl)ethyl]benzoyl]amino]pentanedioic acid (CAS registry number:150399-23-8). (B) C16H15N5O7S2 (6R,7R)-7-{[2-(2-amino-1,3- thiazol-4-yl)-2-(carboxy methoxyimino)acetyl]amino}-3-ethenyl-8-oxo-5-thia- 1- azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid (CAS registry number:79350-37-1).