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-[(1R)-1-(2,4-dichlorophenyl)ethyl]-1-methyl-3-[(3R)-1-pyrimidin-2-ylpiperidin-3-yl]urea by IUPAC nomenclature, provide its molecular formula.
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C19H23Cl2N5O
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