You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (E)-N-[5-(2-amino-4-methyl-5,6-dihydro-1,3-thiazin-4-yl)-2-fluorophenyl]-3-[3-(trifluoromethyl)phenyl]prop-2-enamide into its molecular formula.
user
C21H19F4N3OS
assistant