Fulvestrant Impurity B

Chemical Name: 7α-[9-[(4,4,5,5,5-pentafluoropentyl)sulfonyl]nonyl]estra-1,3,5(10)-triene-3,17β-diol (as per EP) ; Estra-1,3,5(10)-triene-3,17-diol,7-[9-[(4,4,5,5,5-pentafluoro pentyl)sulfonyl]nonyl]-(7α,17β) (as per USP)

Smile: C[C@@]12[C@@H](O)CC[C@@]1([H])[C@]3([H])[C@H](CCCCCCCCCS(CCCC(F)(C(F)(F)F)F)(=O)=O)CC4=C(C=CC(O)=C4)[C@@]3([H])CC2