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 4-(4-cyclobutylpiperazin-1-yl)-7-[(2-methoxyphenyl)methyl]-6,8-dihydro-5H-pyrido[3,4-d]pyrimidine is given. What is its corresponding molecular formula?
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C23H31N5O
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