You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
ethyl 5-amino-4-cyano-3-[(3-morpholin-4-ylsulfonylbenzoyl)oxymethyl]thiophene-2-carboxylate is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H21N3O7S2
assistant