You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 1-[2-[[3-bromo-5-(2-chlorophenyl)pyrazolo[1,5-a]pyrimidin-7-yl]amino]ethyl]-3-[(2,4-dichlorophenyl)methyl]urea by IUPAC nomenclature, provide its molecular formula.
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C22H18BrCl3N6O
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