You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named N-(1,1-dioxothiolan-3-yl)-2-[2-(4-methoxyphenyl)ethylamino]pyridine-4-carboxamide by IUPAC nomenclature, provide its molecular formula.
user
C19H23N3O4S
assistant