Synonyms: 2H-1-Benzopyran-2-one,4-methyl-6,7-bis(sulfooxy)-, bismuth salt (3:2) (9CI); Coumarin,6,7-dihydroxy-4-methyl-, bis(hydrogen sulfate), bismuth(3+) salt (3:2) (8CI);Coumarin, 6,7-dihydroxy-4-methyl-, bis(hydrogen sulfate), dibismuth salt (7CI);S 539