You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named ethyl 3,5-dimethyl-4-oxo-2-sulfanylidene-1H-pyrrolo[3,2-d]pyrimidine-7-carboxylate by IUPAC nomenclature, provide its molecular formula.
user
C11H13N3O3S
assistant