Synonyms: 9,11-Epoxy-9H-cyclopenta[a]phenanthrene, pregna-1,4-diene-3,20-dione deriv., Betamethasone 9,11-epoxide,Pregna-1,4-diene-3,20-dione, 9,11-epoxy-17,21-dihydroxy-16-methyl-, (9β,11β,16β)-, 9β-Pregna-1,4-diene-3,20-dione, 9,11β-epoxy-17,21-dihydroxy-16β-methyl- (6CI,7CI,8CI), 9,11β-Epoxy-17,21-dihydroxy-16β-methyl-9β-pregna-1,4-diene-3,20-dione