You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-[2-(2,5-difluorophenyl)ethyl]-2-methyl-3-[(5-methyl-1,3-thiazol-2-yl)methyl]guanidine The above is the IUPAC name of a molecule. Write its molecular formula.
user
C15H18F2N4S
assistant