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 (1R,5R,6R,7S)-N-[(4-fluorophenyl)methyl]-4-oxo-3-(thiophen-2-ylmethyl)-10-oxa-3-azatricyclo[5.2.1.01,5]dec-8-ene-6-carboxamide ?
user
C21H19FN2O3S
assistant