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 ethyl (4R)-4-methyl-2-oxo-6-[(2-oxo-5-thiophen-2-yl-1,3,4-oxadiazol-3-yl)methyl]-3,4-dihydro-1H-pyrimidine-5-carboxylate into molecular formula.
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C15H16N4O5S
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