You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
methyl 2-[[6-methyl-3-(2-methylpropyl)-4-oxo-5H-pyrrolo[3,2-d]pyrimidin-2-yl]sulfanyl]acetate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C14H19N3O3S
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