You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[3-[(4-benzylpiperidin-1-yl)methyl]-4,5,6,7-tetrahydro-1-benzothiophen-2-yl]-2-fluorobenzamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C28H31FN2OS
assistant