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-[8-(butylamino)-2-methyl-4-(4-methylphenyl)-3,4-dihydro-1H-isoquinolin-1-yl]acetamide is given. What is its corresponding molecular formula?
user
C23H31N3O
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