You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule (1R,2R,3R,4R)-3-[(3-propoxycarbonyl-5,6-dihydro-4H-cyclopenta[b]thiophen-2-yl)carbamoyl]bicyclo[2.2.2]oct-5-ene-2-carboxylic acid into molecular formula.
user
C21H25NO5S
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