You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-[6,8-dioxo-3-(2-piperidin-4-ylethyl)-1-oxa-2,7-diazaspiro[4.4]non-3-en-7-yl]propanoic acid The above is the IUPAC name of a molecule. Write its molecular formula.
user
C16H23N3O5
assistant