You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named N-(2,5-dichlorophenyl)-3-[4-(6-methoxypyrazin-2-yl)piperazin-1-yl]propanamide is given. What is its corresponding molecular formula?
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C18H21Cl2N5O2
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