The name/synonym for ligand BU3 (curated from ChEBI, PubChem, and PDB databases):

1(R,R)-BUTANE-2,3-DIOL
2(R,R)-(-)-BUTANE-2,3-DIOL
3(2R,3R)-BUTANE-2,3-DIOL
4(R,R)-2,3-BUTANEDIOL
5(R,R)-2,3-BUTYLENE GLYCOL