You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 3-methyl-2-[[4-[5-(4-methylsulfanylphenyl)-1,2-oxazol-3-yl]phenyl]sulfonylamino]butanoic acid into molecular formula.
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C21H22N2O5S2
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