You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[(4S)-4-[5-(2-azaspiro[3.3]heptan-6-yl)-1,3,4-oxadiazol-2-yl]-3-ethyl-2-oxo-1,3-diazepan-1-yl] hydrogen sulfate is the IUPAC name of a molecule. Please give its molecular formula.
user
C15H23N5O6S
assistant