You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule 5,6-dimethyl-3-[(4-methylpyridin-3-yl)methyl]-2-sulfanylidene-1H-thieno[2,3-d]pyrimidin-4-one .
user
C15H15N3OS2
assistant