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 N-[(1R)-1-(2,5-dimethylphenyl)ethyl]-3-(2-oxo-5-thiophen-2-yl-1,3,4-oxadiazol-3-yl)propanamide into molecular formula.
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C19H21N3O3S
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