You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[(1R,2R,3R)-2,3-dimethylcyclohexyl]-2-(5,6-dimethylthieno[2,3-d]pyrimidin-4-yl)sulfanylacetamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H25N3OS2
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