The name/synonym for ligand FUM (curated from ChEBI, PubChem, and PDB databases):

1FUMARIC ACID
2(2E)-BUT-2-ENEDIOIC ACID
3FUMARSAEURE
4(2E)-2-BUTENEDIOIC ACID
5TRANS-1,2-ETHYLENEDICARBOXYLIC ACID
6(E)-2-BUTENEDIOIC ACID
7TRANS-BUT-2-ENEDIOIC ACID
8E297
9TRANS-BUTENEDIOIC ACID