You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[[(3R)-3-aminopyrrolidin-1-yl]methyl]-5,6-dimethyl-3H-thieno[2,3-d]pyrimidin-4-one is the IUPAC name of a molecule. Please give its molecular formula.
user
C13H18N4OS
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