You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 5,6-dimethyl-2-[[2-(4-methylphenyl)-1,3-thiazol-4-yl]methylsulfanyl]-3-(pyridin-3-ylmethyl)thieno[2,3-d]pyrimidin-4-one by IUPAC nomenclature, provide its molecular formula.
user
C25H22N4OS3
assistant