You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule ethyl (2S,3aS)-7-(1,2-benzoxazol-3-yl)-4-methyl-6-oxo-2-prop-1-en-2-yl-2,3-dihydro-1-benzofuran-3a-carboxylate into molecular formula.
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C22H21NO5
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