Synonyms: (2S)-2-[[4-[[(6S)-2-amino-5-formyl-4-oxo-1,6,7,8-tetrahydropteridin-6- yl]methylamino]benzoyl]amino]pentanedioic acid;(-)-N-[4-[[[(6S)-2-Amino-5-formyl-1,4,5,6,7,8-hexahydro-4-oxopteridin-6β-yl]methyl]amino]benzoyl]-L-glutamic acid;(6S)-5-Formyltetrahydrofolic acid;(6S)-Leucovorin;(S)-Leucovorin