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 [2-(3,4-dichlorophenyl)-2-oxoethyl] 2-[(2R)-3-oxo-4H-1,4-benzoxazin-2-yl]acetate into molecular formula.
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C18H13Cl2NO5
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