You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(5S)-3-methyl-9-(3-pyridin-3-ylpropyl)-1-oxa-3,9-diazaspiro[4.5]decan-2-one The above is the IUPAC name of a molecule. Write its molecular formula.
user
C16H23N3O2
assistant