You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[(2-butoxypyridin-3-yl)methyl]-5-oxo-4-azatricyclo[4.2.1.03,7]nonane-3-carboxamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C19H25N3O3
assistant