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 6-[4-[(2S)-1-[(3-methyl-1,2-oxazol-5-yl)amino]-1-oxopropan-2-yl]piperazin-1-yl]pyridine-3-carboxylate into molecular formula.
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C19H25N5O4
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