You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[2-oxo-2-[[(2R)-4-phenylbutan-2-yl]amino]ethyl] (3S)-2,3-dihydro-1,4-benzodioxine-3-carboxylate is the IUPAC name of a molecule. Please give its molecular formula.
user
C21H23NO5
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