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 7-chloro-3-methyl-1-[[5-(4-methylphenyl)-1,3,4-oxadiazol-2-yl]methyl]quinoxalin-2-one into molecular formula.
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C19H15ClN4O2
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