You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[(1R,3R,4R,5S)-3-[6-[2-(3-fluorophenyl)ethynyl]purin-9-yl]-4,5-dihydroxy-2-oxabicyclo[3.1.0]hexan-6-yl] sulfamate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C18H14FN5O6S
assistant