You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 2-[6-(3-bromo-4-hydroxy-5-methoxyphenyl)-4-methyl-2-oxo-5-propan-2-yloxycarbonyl-1,6-dihydropyrimidin-3-yl]acetic acid by IUPAC nomenclature, provide its molecular formula.
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C18H21BrN2O7
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