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system
Provide the molecular formula for the IUPAC named substance tert-butyl N-[4-(5-bromo-2-fluorophenyl)-5,5-difluoro-4-methyl-1,9-dioxa-3-azaspiro[5.5]undec-2-en-2-yl]carbamate .
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C20H24BrF3N2O4
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