You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-(4-aminothieno[2,3-d]pyrimidin-2-yl)sulfanyl-1-(2,6-dimethylpiperidin-1-yl)ethanone The above is the IUPAC name of a molecule. Write its molecular formula.
user
C15H20N4OS2
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