You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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N-[3-oxo-1-phenyl-3-(1-phenyl-3,4-dihydro-1H-pyrrolo[1,2-a]pyrazin-2-yl)propyl]acetamide is the IUPAC name of a molecule. Please give its molecular formula.
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C24H25N3O2
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