You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
methyl 3-(4-benzyl-5-sulfanylidene-1H-1,2,4-triazol-3-yl)naphthalene-2-carboxylate is the IUPAC name of a molecule. Please give its molecular formula.
user
C21H17N3O2S
assistant