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 (2R)-2-[methyl-[2-[[5-(2-methylpropyl)-1,3,4-thiadiazol-2-yl]amino]-2-oxoethyl]amino]butanamide into molecular formula.
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C13H23N5O2S
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