You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule N-[(3-chlorophenyl)methyl]-10-ethyl-9-oxa-1-azatricyclo[6.3.1.04,12]dodeca-2,4(12),5,7-tetraene-2-carboxamide .
user
C20H19ClN2O2
assistant