You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-[[(1S,9S)-8-oxa-2,3,4,11-tetrazatricyclo[7.4.0.02,6]trideca-3,5-dien-11-yl]methyl]benzonitrile is the IUPAC name of a molecule. Please give its molecular formula.
user
C16H17N5O
assistant