You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[[4-amino-5-[(4-methoxyphenyl)methyl]-1,2,4-triazol-3-yl]sulfanylmethyl]-5,6-dimethyl-3H-thieno[2,3-d]pyrimidin-4-one is the IUPAC name of a molecule. Please give its molecular formula.
user
C19H20N6O2S2
assistant