You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule N-[(3-chlorophenyl)methyl]-2-[[2-(2,3-dihydro-1,4-benzodioxin-6-ylamino)-2-oxoethyl]-ethylamino]acetamide into molecular formula.
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C21H24ClN3O4
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