You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-butyl-N-[3-[[5-(4-methoxyphenyl)-1,3,4-thiadiazol-2-yl]amino]-3-oxopropyl]-3-methylbutanamide into its molecular formula.
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C21H30N4O3S
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