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system
What is the molecular formula of the molecule identified by (5'aS,6'S,9'aS)-2'-bromo-6',9'a-dimethyl-3'-phenylspiro[1,3-dioxolane-2,7'-4,5,5a,6,8,9-hexahydrobenzo[e]benzimidazole] ?
user
C21H25BrN2O2
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