You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named tert-butyl 3-[7-bromo-4-(1,1-difluoro-2-hydroxy-2-methylpropoxy)-1,3-benzothiazol-2-yl]-3,6-diazabicyclo[3.1.1]heptane-6-carboxylate by IUPAC nomenclature, provide its molecular formula.
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C21H26BrF2N3O4S
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