You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 2-ethoxy-N-(4-pyrrolidin-1-ylphenyl)-5-(1,1,3-trioxo-1,2-thiazolidin-2-yl)benzenesulfonamide by IUPAC nomenclature, provide its molecular formula.
user
C21H25N3O6S2
assistant