You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Provide the molecular formula for the IUPAC named substance 1H-indol-2-yl-(11-methyl-8-oxa-2,11-diazaspiro[5.6]dodecan-2-yl)methanone;2,2,2-trifluoroacetic acid .
user
C21H26F3N3O4
assistant