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

1SPIRILLOXANTHIN
23,3',4,4'-TETRADEHYDRO-1,1',2,2'-TETRAHYDRO-1,1'-DIMETHOXY-PSI,PSI-CAROTENE
3RHODOVIOLASCIN
4(3E,3'E)-1,1'-DIMETHOXY-3,3',4,4'-TETRADEHYDRO-1,1',2,2'-TETRAHYDRO-PSI,PSI-CAROTENE