You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[4-[1-(3-fluorophenyl)-3,6-dimethyl-4H-pyrazolo[3,4-d][1,3]thiazin-4-yl]phenoxy]acetamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H19FN4O2S
assistant