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-(4-acetylphenyl)-4-[1,3-dimethyl-7-[(4-methylphenyl)methyl]-2,6-dioxopurin-8-yl]piperazine-1-carbothioamide is given. What is its corresponding molecular formula?
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C28H31N7O3S
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