You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
ethyl 5-[2-(2-ethoxy-2-oxoethyl)sulfanylacetyl]-2,4-dimethyl-1H-pyrrole-3-carboxylate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C15H21NO5S
assistant