You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 1-(4,5-dimethyl-1,3-oxazol-2-yl)-3-[1-(2-oxo-1H-pyrazin-3-yl)piperidin-3-yl]urea by IUPAC nomenclature, provide its molecular formula.
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C15H20N6O3
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