2-[[4-[(2,4-diaminopyrido[2,3-d]pyrimidin-6-yl)methyl-methylamino]benzoyl]amino]pentanedioic acid

diethyl 2-[[4-[(2,4-diaminopyrido[2,3-d]pyrimidin-6-yl)methylamino]benzoyl]amino]pentanedioate

5-去氮杂氨基蝶呤

diethyl 5-deazafolate