You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule (2R)-2-[6-(5-ethyl-3-methyl-1,2-oxazol-4-yl)pyridin-2-yl]-4-methylsulfonylmorpholine into molecular formula.
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C16H21N3O4S
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