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-[(2S)-2-(3,5-dimethyl-1,2-oxazol-4-yl)pyrrolidin-1-yl]-2-(5-methyl-2-phenyl-1,3-oxazol-4-yl)ethanone by IUPAC nomenclature, provide its molecular formula.
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C21H23N3O3
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