You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(2S)-N-(8-azabicyclo[3.2.1]octan-3-yl)-2-[(2-methoxyacetyl)amino]-3-methylbutanamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C15H27N3O3
assistant