You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[2-[(3-methyl-1,1-dioxothiolan-3-yl)amino]-2-oxoethyl] 3-oxo-4H-1,4-benzothiazine-6-carboxylate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C16H18N2O6S2
assistant