You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-[3-(2-amino-4,4a,5,7-tetrahydrofuro[3,4-d][1,3]thiazin-7a-yl)-4-fluorophenyl]-5-(difluoromethyl)pyridine-2-carboxamide into its molecular formula.
user
C19H17F3N4O2S
assistant