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 2-chloro-N-[(3-ethyl-1,2,4-oxadiazol-5-yl)methyl]-5-[(4-methoxyphenyl)-methylsulfamoyl]-N-methylbenzamide into molecular formula.
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C21H23ClN4O5S
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