You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Name the molecular formula for the molecule established as (2S)-N-(2,5-dimethoxyphenyl)-2-methyl-3-oxo-4H-1,4-benzothiazine-6-carboxamide using the IUPAC nomenclature.
user
C18H18N2O4S
assistant