You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[4-cyano-3-fluoro-5-[4-(2-methoxypyrimidin-5-yl)piperazin-1-yl]phenyl]methyl N-(diaminomethylidene)carbamate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C19H21FN8O3
assistant