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 acetylene;(4S)-4-(3-chloro-5-fluorophenyl)-6,8-diazatricyclo[4.3.0.02,4]non-1(9)-ene-7-thione ?
user
C15H12ClFN2S
assistant