You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
What is the molecular formula of the molecule identified by (2S)-2-[5-(4-chlorophenyl)tetrazol-2-yl]-1-(1,4-dioxa-8-azaspiro[4.5]decan-8-yl)butan-1-one ?
user
C18H22ClN5O3
assistant