You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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4-[[5-amino-6-[(5-methyl-1,2-oxazol-3-yl)amino]pyrimidin-4-yl]amino]-N,N-diethylbenzenesulfonamide The above is the IUPAC name of a molecule. Write its molecular formula.
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C18H23N7O3S
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