You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule N-[2-[3-(4-methoxyphenyl)-1,2,4-oxadiazol-5-yl]ethyl]-1-(3-methylphenyl)methanesulfonamide into molecular formula.
user
C19H21N3O4S
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