You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Provide the molecular formula for the IUPAC named substance N,N-diethyl-3-oxo-4-[2-oxo-2-(pyridin-3-ylamino)ethyl]-1,4-benzothiazine-6-carboxamide .
user
C20H22N4O3S
assistant