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What is the molecular formula of the compound with this IUPAC name (1R,2R,6R,7R)-4-[(Z)-(3-bromo-5-ethoxy-4-methoxyphenyl)methylideneamino]spiro[4-azatricyclo[5.2.1.02,6]dec-8-ene-10,1'-cyclopropane]-3,5-dione ?
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C21H21BrN2O4
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