You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[[5-(5-chloro-2-methoxyphenyl)-1H-1,2,4-triazol-3-yl]sulfanylmethyl]-5,6,7,8-tetrahydro-3H-[1]benzothiolo[2,3-d]pyrimidin-4-one is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H18ClN5O2S2
assistant