You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (3aR,4S)-4-ethoxy-6a-[(S)-(4-methylphenyl)sulfinyl]-3-phenyl-3a,4-dihydrofuro[3,4-d][1,2]oxazol-6-one into its molecular formula.
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C20H19NO5S
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