You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
tert-butyl (6S)-6-[4-(1-cyanocyclopropyl)phenyl]-9-oxo-10-oxa-12-thia-3,4,8-triaza-6-azoniatricyclo[6.2.1.12,5]dodeca-2,4-diene-6-carboxylate is the IUPAC name of a molecule. Please give its molecular formula.
user
C21H22N5O4S+
assistant