You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(1R)-7-fluoro-1-methyl-N-(3-methylsulfanylpropyl)-3,4-dihydro-1H-isoquinoline-2-carboxamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C15H21FN2OS
assistant