You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named (1S,4R)-5-(5-ethylthiophen-2-yl)sulfonyl-2-oxa-5-azabicyclo[2.2.1]heptan-3-one by IUPAC nomenclature, provide its molecular formula.
user
C11H13NO4S2
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