You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 2-[7-(3-methylbut-2-enyl)-2,6-dioxo-1-phenacyl-8-piperazin-1-ylpurin-3-yl]acetic acid into molecular formula.
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C24H28N6O5
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