You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 3,5-dimethyl-4-[(1-methyl-6-oxo-8-piperazin-1-yl-7H-purin-2-yl)oxy]benzoic acid into molecular formula.
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C19H22N6O4
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