You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (4aR)-7a-phenyl-6-pyrimidin-2-yl-4,4a,5,7-tetrahydropyrrolo[3,4-d][1,3]thiazin-2-amine into its molecular formula.
user
C16H17N5S
assistant